Size cable tray, ladder and basket runs for every service on the bracket (power, fire, data, audio-visual, specialist lighting), arrange them by tier, check the supports, and print the record that proves it.
Standards applied
BS 7671BEAMABS EN 61537On-Site Guide Appendix DBS 8519BS EN 61914
Select BS 8519 to apply the fire-rated route.
How this works
- Add a run. A run is one containment on the bracket serving one service: a tray, ladder or basket sized here, or a trunking already sized in the Trunking Size Calculator and added here for the tier arrangement, the fill check and the bracket loading. Drop its cables in, or pick a typical arrangement and edit it.
- Sizing: Runs are sized single layer from cable mix and spacing, or on bunched fill within the usable depth for Data / comms, Audio-visual, Specialist lighting and Extra-low voltage / controls with Lay on Auto or Bunched. Each width, plus spare capacity, is rounded up to the next standard size, split parallel or stacked beyond the largest standard tray. Size trunking in the Trunking Size Calculator. Each run's grouping factor (Cg) is provided, or the reason none is printed. For Engineering Toolkit subscribers, each run is also checked for load, fixing spacings and fault restraint.
- Arrange the tiers and read the bracket. Engineering Toolkit subscribers assign each run to a tier, and read the segregation checks for the mixed services and the drop rod sizes for the whole bracket (BS 8519 Annex I and Table E.2 on fire-rated routes).
PD Tray is free to run, no signup: after 3 anonymous sessions, you enter an email address to continue. In the free version you size one run at a time, on tier 1. Engineering Toolkit subscribers get more runs, more tiers and the typical arrangements with more than one run or tier. They also get the working behind each grouping factor, the fixing and support panels, the editable Excel / Word / comma-separated values (CSV) / Text exports and My Projects.
Add a run
Recommended containment: -
Runs0
Tiers0
Cables0
Cable grouping factor (Cg): BS 7671 Tables 4C1 / 4C4 / 4C5
Cable fixing & fault restraint: OSG Appendix D / BS EN 61914
Support system: bracket drop-rod loading
v2.23.0 · Verified
BS 7671:2018+A4:2026 App 4 (Ref Methods E/F, grouping Tables 4C1/4C4/4C5), OSG App D Table D1, BS EN 61914, BS EN 61439-1 Table 7, BS 8519:2020 (Table E.2, Annex I; 6.1, 7.1, 7.3 and clause 11 for life safety supplies), BS EN 61537
- 2,553brackets enumerated on 2.12.0 (30/09/2026) against a separate calculation of the same method from the same data tables, no difference
- 58automated checks re-run before every release; the calculation checks test a Python copy of the method, not the tool's output, against hand-worked figures
- 143cables in the shared data store, from published datasheets
- 7cases printed to Portable Document Format (PDF) and measured on 2.12.0, every sample arrangement included: text size, page numbers and the drawing page with its frame
- Last reviewed
- September 2026
- Data basis
Show the full record
Containment self-weights: Legrand Swifts, Unitrunk Speedway, Cablofil catalogues. Cleats: Ellis Patents datasheets (Vulcan+ DS03E iss. 06, Atlas DS13E iss. 03, Emperor 07/2026). Cables: 143 in the shared store, from Prysmian and supplier datasheets. SWA to BS 5467 from the Eland Cables dimensions tables, with the 5-core 70 and 95mm² sizes from the Cleveland Cable BS 5467 datasheet (the Eland table stops at 50mm²). Singles: 6491X PVC and 6491B LSZH, 15 sizes each from 2.5 to 300mm², from the Cleveland Cable datasheets. Cat 6A from Brand-Rex and Leviton datasheets, AV and control from Belden technical data. Rod capacities: BS 8519:2020 Table E.2.
- Validated against
02/11/2026 (2.23.0): A split run with spaced cables can need fewer or narrower trays, never more. Its grouping factor can change, be printed where 2.22.0 printed none, or not be printed where a tray's circuits exceed the BS 7671 table. Width remedies with a figure are worked out again, shown only where they pass and no passing check then fails. With the Engineering Toolkit, that run's drop rod can change by one size, load and grouping remedies are worked out again, and a split run's load is checked on its heaviest tray with the spare, so it can pass where it failed.Show the full record
- 01/11/2026 (2.22.0): On a split run, cables are now shared by one rule; a circuit entered as separate cable lines can be on different trays. The number of trays, widths, bracket and drop rod loads and grouping factor can differ from 2.21.1. Runs whose required width equals a tray width can now be one width narrower or one tray fewer. Without a containment weight entered, ladder starts at 150 mm, heavy duty tray at 75 mm and basket stops at 600 mm. With the cables reordered for the return flanges, some medium and heavy duty tray runs are narrower, a few wider.
- 30/10/2026 (2.21.0): A listed cable's cores, armour and fire resistance are read from PD Cable Database. SPLITC-3c35-LSOH, SPLITC-1c35-PVC and STRC-1c35-CNE have none stated: dependent checks, Reference Method included, are not made. In trefoil runs the last two lie flat: wider or more trays (REVIEW WIDTH or SPLIT) and higher bracket and drop rod loads can result. With these three or an unanswered Custom single-core cable, the force between conductors can be higher. Cables marked in the picker are named on the run. A report saved from 2.21.0 lists later cable changes when re-opened. Without the cable list loaded, no result is shown.
- 28/10/2026 (2.20.1): The trunking fill item of the report and the trunking width and depth tips no longer call every width x depth (W x D) nominal: W x D is the catalogue size, or the internal size of a Custom size section or a fire-rated system typed in manually. Where a run's grouping factor is read from the perforated cable tray rows of BS 7671 Tables 4C4 and 4C5, the report states that these are for horizontal perforated cable tray, so a run on vertical perforated cable tray is not checked by them. Calculation results are unchanged for the same inputs.
- 28/10/2026 (2.20.0): A re-opened report lists each run size, verdict and bracket changed since saving. Entered cleat spacing and assembly position, a loaded trunking schedule edited in PD Tray and the automatic fire route get a line where their basis changed. Known power cables on Data, Audio-visual and Extra-low voltage runs are named in a warning. Trunking runs are now checked, and their Utilisation shown, against the 45% space factor with the spare kept free. Other calculation results change only for a spare of 1 or less (now a percentage) or with decimals, and rod centres no wider than the widest tier.
- 25/10/2026 (2.19.5): Runs of over 24 cables with trefoil groups and cables laid flat now have the mixed formation caption, warning and drawing sheet note, like smaller runs. The non-sheathed cable warning quotes the trunking condition of BS 7671 Reg 521.10.1. For unperforated tray, the printed report states how Table 4C4 is read between rows and columns. The trefoil spacing sentence names every kind of lay unit. In the free version, the grouping line gives the number of trays entered. Widths, the number of trays a run needs, grouping factors, verdicts, loads and drop rods are unchanged for the same inputs.
- 24/10/2026 (2.19.4): For multicore runs laid single layer on unperforated tray with more than one tier, the grouping factor (Cg) is now read from BS 7671 Table 4C4; where none can be read, the reason is printed. Re-check those runs. Runs on tray, ladder or basket with protective conductor cables have a note. The "How this works" list states which checks are for Engineering Toolkit subscribers. Two free version texts no longer name the per-rod loads or My Projects. The trefoil, cleat and trunking self-weight sentences are reworded. Widths, verdicts, the load check and drop rods are unchanged for the same inputs.
- 24/10/2026 (2.19.3): On the page for sizing another PD tool's tray runs, runs on tray, ladder or basket with a cable from "Single-core low smoke zero halogen (LSZH) 6491B (trunking runs only, Reg 521.10.1)" are now answered "not worked out", with no width. PD Tray's own page marks them ENCLOSE. A program fault while one report is read back affects only that report. There is nothing to re-check: on PD Tray's own page, widths, the number of trays, grouping factors, verdicts, the load check, drop rods, bracket totals and fixing spacings are unchanged for the same inputs, as is the free version.
- 23/10/2026 (2.19.2): On the page for sizing another PD tool's tray runs, trunking runs and runs set too narrow are now answered "not worked out", with a reason and no width. Runs whose cables have no diameter are answered the same way, not left out as runs with no cables. One report not worked out no longer leaves the others with no width. There is nothing to re-check: PD Tray's own page, results for the same inputs and the free version are unchanged. The brand line still prints once on Engineering Toolkit printed reports, at the end of the written pages.
- 22/10/2026 (2.19.1): Engineering Toolkit printed reports have the brand line at the foot of the written pages, before the drawing sheets: "UK electrical design. We make the tools and Revit content we use." The free version has no printed report and is unchanged. A page for sizing another PD tool's tray runs with PD Tray's calculation is added for Engineering Toolkit subscribers; no PD tool uses it yet, so you see no change. There is nothing to re-check: widths, the number of trays, grouping factors, verdicts, the load check, drop rods, bracket totals and fixing spacings are unchanged for the same inputs.
- 21/10/2026 (2.19.0): The load check, bracket and worst rod loads are Engineering Toolkit only; the free version's Checks list states the check is not made. Tier bearers are counted at 2.6 kg/m (Philip Grahame CH101), not 2.2: re-check drop rods, as one can be a size larger, or exceed M20 and FAIL. FP400, FP500 and FP600 are drawn as armoured cables and take the longer armoured fixing spacings of On-Site Guide Table D1 (BS 7671:2018+A4:2026 edition). Indicative safe working loads below 10 kg/m are shown to one decimal place. Widths, grouping factors and load check verdicts are unchanged.
- 21/10/2026 (PD Cable Database 1.0.4): steel wire armoured (SWA) cables have the largest figures in three makers' datasheets. 52 are added and seven are changed: 3-core 25 mm² is 25.2 mm, not 23.6 mm; 3-core 6, 5-core 6, 10, 16 and 25, and 4-core 400 mm² are heavier. A run can need one standard width wider, one more tray or larger drop rods, be over a chosen width or 45% trunking space factor, or fail the load check; never the reverse. Grouping factor (Cg) can change. Re-check runs with these cables: reopened saved reports have the new figures and no note of the change.
- 18/10/2026 (2.18.0): The tool is now PD Tray. Free use is one run at a time, on tier 1; more runs and tiers are greyed out. Saved multi-tier work is never deleted. A load above the 3.0 m indicative safe working load (SWL) is a FAIL at longer spans, not "Manufacturer SWL needed". Rod loads on side by side splits of three or more cable lines, or of two with single-core cables in trefoil, are now the worst over every order of the cables. They can be higher, and drop rods one size larger: re-check them. Widths and grouping factors are unchanged.
- 16/10/2026 (PD Cable Database 1.0.3): six FP200 Gold cables (2-core 1.5, 2.5 and 4, 3-core 2.5 and 4, 4-core 2.5 mm²) have Prysmian's current figures; steel wire armoured (SWA) 3-core 25 mm² is 23.6 mm, not 25.5 mm. A run can need one standard width narrower or one tray fewer, or fit within a chosen width or 45% trunking space factor; never the reverse. Bracket load, drop rod and Grouping factor (Cg) can change either way, with a larger rod only on the BS 8519 fire route. Re-check runs with these cables: reopened saved reports have the new figures and no note of the change.
- 16/10/2026 (2.17.1): The printed report's top line names every run, and the bracket, needing action in Findings. Drawing sheets show any chosen width with its Fill. Fill, there and in the tool, includes any flange allowance and reads at least 101% on an OVER run. Exports include only drawings that match the report. Fire-rated Trunking from My Projects takes its internal size. Changing a run's size, load or support clears the designer's confirmation and can set aside entered counts. In reports saved before 2.17.1, re-check layouts, entered counts and 0% spares. Widths, grouping factors and rods are unchanged for the same inputs.
- 14/10/2026 (2.17.0): Cables with no diameter or weight, baskets over 600 mm with no self-weight and spans over 3.0 m with no manufacturer's safe working load are not checked. Custom cables now have four questions; until each is answered, its checks are listed as not checked and saved runs can be wider. Re-check split runs (grouping factors can be lower or not printed, and rods larger unless stacked) and bunched fills on tray (wider or OVER; the bracket can be wider, its rods one size larger or smaller). No grouping factor is printed for STRC-1c35-CNE or SPLITC-1c35-PVC runs: work it out manually.
- 11/10/2026 (PD Cable Database 1.0.2): 24 FP400 cables have Prysmian's current figures: larger diameters for 3-core 1.5 to 16 and 35, 4-core 1.5 to 35 and 240 mm², smaller for 3-core 70, 4-core 70 to 185, 300 and 400 mm². Width, tray count, bracket load, drop rod and Grouping factor (Cg) can change; a chosen width or 45% trunking space factor can now be exceeded, or no longer exceeded. On-Site Guide Table D1 now applies to 4-core 70 mm², with wider spacings for 3-core 2.5 and 4-core 6 mm². Re-check FP400 runs: reopened saved reports have the new figures and no note of the change.
- 11/10/2026 (PD Cable Database 1.0.1): the eight aluminium wire armoured (AWA) cables have Eland Cables' 0.6/1 kV figures, not 1.9/3.3 kV. From 150 mm² up, diameters are 1.1 to 4.2 mm larger: runs can need one size wider or one more tray. AWA-120-1c is 0.8 mm smaller: runs can need one size narrower or one tray fewer. Weights are 7% to 22% lower; bracket load, drop rod and Grouping factor (Cg) can rise or fall. AWA-400-1c and AWA-500-1c are now beyond On-Site Guide Table D1. Re-check AWA runs sized before this release: reopened saved reports have the new figures and no note of the change.
- 08/10/2026 (2.16.0): the drawing headings read CROSS-SECTION, SECTION and LOADS; the sheet titles read CROSS-SECTION and SECTION. At any spare, including the default 25%, re-check these, which can be wider: medium and heavy duty trays with under 15 mm of width free; trefoil runs with spacing and two single cores left over; and split runs, where a tray could be narrower than its cables. Medium duty trays with 21 to 30 mm cables can be one size smaller, or one tray fewer. With more or fewer trays, a run's Grouping factor (Cg) can change. The cables' kg/m and Reference Method are unchanged.
- 08/10/2026 (2.15.0): single layer basket runs use wire mesh tray grouping factors, not perforated tray: most rise, three fall by 0.01 (two per basket). No factor is printed for more trays than Table 4C4 or 4C5 lists. Medium duty tray flanges are drawn inwards: with no spare, the tray can be one size larger, and heavier, where cables over 21 mm would sit under them. Re-check these cases. Ladder and basket callouts no longer say "return flanges". The drop-rod loading card is beside the Bracket loading drawing on wide windows. The grouping line's missing space is fixed. Otherwise the calculations are unchanged.
- 01/10/2026 (2.14.0): the Bracket elevation is now called Bracket loading. Grouping factors are no longer printed beyond the limits of BS 7671 Table 4C4 (more than 6 cables per tray when spaced, or more than 9 on two or more trays) or Table 4C5 (more than 3 three-phase circuits per tray). A line names the limit and Table 4C1 NOTE 7. The factor printed for these runs before 2.14.0 overstates current-carrying capacity: re-check cables sized with it. In 2.13.1, the screening room bracket's printed Cross-section showed rod B's size and "minimum" on separate lines; this is fixed. Otherwise the calculations are unchanged.
- 01/10/2026 (2.13.1): on the drawing sheets, in the tool and in print, the Notes heading now has more space above it: about 5.4 mm in print (it was 0.4 to 3.4 mm). In 2.13.0, the Notes, Abbreviations and Key column overlapped the Drawing data heading on the printed Cross-section sheet of the screening room bracket with 8 or 10 runs. It is now drawn 10 mm wider in print where it would not fit above the Drawing data. The pictures in the exports show the same changes. The calculations and wording are unchanged in the tool, the printed report and the exports.
- 30/09/2026 (2.13.0): the Bracket elevation is now a drawing sheet, like the cross-section. It shows where each load acts and, in the Engineering Toolkit, the run loads, rod loads and minimum drop rod size. Before any cable is entered, a drawing marked SAMPLE is shown and kept out of the result, report and exports. In the Toolkit, both sheets can print at the end of the report, each on its own A4 landscape page, and appear in the Word and Excel exports. The pictures in an export made straight after a change now show the changed arrangement. The calculations are unchanged.
- 30/09/2026 (2.12.0): the cross-section drawing is now a drawing sheet with callouts, notes, abbreviations and a key. In the Engineering Toolkit, with "Include the cross-section drawing in the report" ticked, the drawing prints on its own A4 landscape page with a run schedule. The Word and Excel exports include a picture of that page. The Specialist lighting lines now name the Lighting, General power and Lighting & power services. The calculations are unchanged. In an automated check of 34 brackets, each drawn on a wide screen, a phone and the printed sheet, no text overlapped or ran outside the sheet frame.
- 30/09/2026 (2.11.0): the cable list was moved to PD Cable Database, a separate plugin on projectdesign.io. The cables in the list, the calculations, the wording shown in the tool, the drawings, the printed report and the exports are unchanged. The same list is used, as before, in the Cable Duct, Conduit and Trunking tools, which are not changed in this release. In an automated check, the cable list in 2.11.0 was identical, byte for byte, to the list in use before this release (143 cables, read on 30/09/2026), whether PD Cable Database was active or not.
- 30/09/2026 (2.10.1): a run of loaded circuits laid Bunched is now sized on its single layer width, so its tray can be wider or narrower: re-check trays sized before 2.10.1. Specialist lighting no longer counts as a loaded tier, so other runs on the same bracket can be given a grouping factor up to 0.06 higher, or one where none was printed because of the tier spacing, but no factor above 20 circuits on one tier. A cable not in the cable list is now kept as a Custom cable and named in a check line. Otherwise the calculations are unchanged.
- 30/09/2026 (2.10.1): the screening room example now has 100 x 50 mm trunking on RUN 2, not 150 x 100 mm, so its total per bracket is 21.18 kg, not 23.53 kg.
- 29/09/2026 (2.10.0): you can now duplicate a run, move a cable between runs and choose the service "Life safety supply". Above 20 circuits, a single layer on one tray is now given no grouping factor, as BS 7671 Table 4C1 gives none. Seven FP600 cables now match the current Prysmian FP600s datasheet. Otherwise the calculations are unchanged. The loading basis now defaults to "Not subject to simultaneous overload"; the grouping factor is unchanged. The containment is drawn 100 mm from the wall by default. Abbreviations are now written out. Re-check cables sized before 2.9.2 on a run of loaded circuits laid Bunched.
- 26/09/2026 (2.9.3): in the Engineering Toolkit, the printed report now includes the Sizing basis section, which it had not printed before, and again gives the SWL each run is checked against. A printed section is no longer located by its title, so rewording a title cannot leave it empty. No calculated value changed. In the printed report and the exports, each run's support system line now gives its total load and names all tiers of a stacked run. The Cross-section drawing and its caption no longer show cable ladder when a cable over 50 mm across is on tray or basket. A References entry for BS 7671:2018+A4:2026 Table 4C1 item 1 was added, and the wording of ten other lines in the tool and the report was corrected. The green for a pass, the amber for a point to check or a warning, and the grey for a neutral mark are now darker, so that any white text on them meets the 4.5:1 contrast that the Web Content Accessibility Guidelines 2.2 require at level AA for text of 12 px; this change applies only to the colours, not to any calculation, result, wording or layout. Apart from these changes, the calculations, the wording shown in the tool, the drawings, the printed report and the exports are unchanged. A new automated check prints 14 arrangements and finds in each printed report every result, check line, factor and sizing step shown in the tool, 1,031 items in all, as whole words at 7 pt or more; it fails on a copy of 2.9.2 with the title of the grouping section changed. The new check, a check of the colours and the header bar, the Table 4C1 item 1 check, the 2,553-bracket enumeration, the 27 random brackets, the 56 hand-calculated checks, the printed report layout check (eight cases) and the audit checks were run on the final build with no finding; the served files matched the release and the page was read.
- 26/09/2026 (2.9.2): a run of loaded circuits with its Lay set to Bunched is now given the grouping factor of BS 7671:2018+A4:2026 Table 4C1 item 1 for the circuits in its bunch. In 2.9.1 it was given a single layer factor, or none. For example, 4 multicore cables bunched on one perforated tray are now given 0.65, not 0.77. Above 20 circuits in a bunch no factor is printed. In the Engineering Toolkit, the grouping panel and the printed report also state the single layer factor of the same cables, except on unperforated tray or where the tier spacing is under 300 mm or not entered. Twelve lines citing a standard were corrected: none now says "must", and a line says "should" or "shall" only where the clause it cites does. Apart from these changes, the calculations, the wording shown in the tool, the drawings, the printed report and the exports are unchanged. A new automated check tests bunched runs of every loaded service on tray, basket and ladder against Table 4C1 item 1, at circuit counts across the table and above 20, and fails on the 2.9.1 build. A check compared 2.9.1 and 2.9.2 on 38 arrangements and found only the corrected lines. The new check, the 2,553-bracket enumeration, the 27 random brackets, the 56 hand-calculated checks, the printed report check (eight cases) and the audit checks were run on the final build with no finding; the served files matched the release and the page was read.
- 26/09/2026 (2.9.1): the simultaneous overload line, the perforated tray definition, the drawing caption of a bunched run and four other lines were corrected. The drawings now have the PD Power Distribution tool's colours and font, and the printed report has the same colours. A guidance pop-out no longer blocks the controls it covers, and on a touch screen it shows only while you are in its field. Apart from these changes, the calculations, the wording shown in the tool, the drawings, the printed report and the exports are unchanged. A new check compared the drawings, the printed report and the report data of 2.9.0 and 2.9.1 on 32 arrangements and found only the colour and font changes and the corrected lines. In the review of 2.9.0, 41 controls were used at desktop and phone width in the free and Engineering Toolkit versions, and every line shown was read against its source. The 2,553-bracket enumeration, the 27 random brackets, the 56 hand-calculated checks, the printed report check (eight cases) and the audit checks were re-run on the final build with no difference; the served files matched the release and the page was read.
- 26/09/2026 (2.9.0): apart from the save and export panel, the panels, buttons and input boxes now have the PD Power Distribution tool's colours and font. The tool name, version and Start again button are now in a dark header bar. On a phone 375 px wide the page no longer scrolls sideways. This was checked with all seven typical arrangements in the Engineering Toolkit version and four in the free version. The program file for the calculations, check lines, drawings, printed report and exports is byte for byte the 2.8.3 file, so the 2,553-bracket enumeration was not re-run. A new automated check reads the colours, font, header bar and drawing tabs at desktop and phone widths, and fails on the 2.8.3 build. The printed report check was re-run on its eight cases with no finding, and each matches its 2.8.3 print page for page. The automated check of the fire alarm note, the automated check built for 2.7.3, the audit checks, the 27 random brackets and the 56 hand-calculated checks were re-run on the final build with no difference. The wording shown in the tool is unchanged apart from the header bar, and every control works as before; the served files matched the release and the page was read.
- 24/09/2026 (2.8.3): the note citing BS 5839-1:2025 35.5 is now shown for fire alarm cables only. The owner found it in the live tool for an FP600 power cable on a General power run. On 2.8.2 every cable type beginning FP (FP200, FP400, FP500 and FP600) was treated as a fire alarm cable for this note, and where such a cable shared a run with other cables the note stated 'move them to a run of their own, or add a dedicated partition' on cable tray, ladder and basket as well as on trunking. Clause 35.5 was read in the standard, and it applies to conduit and trunking only. The owner ruled the same day which cables the note is for: every fire-resistant cable on a Fire alarm run, and FP200 on any other run except a life safety run, where BS 8519 is applied as before. FP400 and FP600 are power cables and FP500 is treated as a life safety cable. On trunking the note now states the clause's recommendation, a compartment reserved solely for the fire alarm cables; on cable tray, ladder or basket it states that there is no requirement in the clause for a separate run, and that a run of their own is good practice. The References line in the report now also states the scope of the clause, and the words 'as arranged here' were removed from its last sentence because they were not true where cables share a run. A new automated check built 1,440 brackets on 2.8.2 and on 2.8.3, 720 in the free version and 720 in the Engineering Toolkit version, for all 12 services, all six containment types and ten sets of cables. On 2.8.3 every note matched the clause and the owner's ruling, and apart from this note and the References line nothing changed in the wording shown in the tool, the drawing, the printed report or the report data; the same check fails on the 2.8.2 build. The duct, conduit and trunking tools were checked for the same fault and do not have it. The 2,553-bracket enumeration, the 27 random brackets, the printed report check and the audit checks were re-run on the final build with no difference; the calculations are unchanged; the served files matched the release and the page was read.
- 24/09/2026 (2.8.2): one cable was added to the cable list, FP600S 5-core 35 mm², with an overall diameter of 39 mm and a weight of 3,300 kg/km from the current Prysmian FP600s datasheet. The same datasheet gives the figures already in the list for the 3-core and 4-core 35 mm² cables, so the new cable follows that edition; the 2014 copy, which gives 37 mm and 3,100 kg/km, was not used. The list is shared, so the cable also appears in the duct and conduit tools. Calculated by hand with 25% spare, one of these cables needs a 50 mm tray and weighs 4.13 kg/m, and four need a 225 mm tray at 16.5 kg/m; the tool gives the same figures. The 2,553-bracket enumeration, the 27 random brackets, the printed report check and the audit checks were re-run on the final build with no difference. The figures for every other cable, the wording shown in the tool, the printed report and the exports are unchanged. After upload, the served files matched the release, and the cable list on the site holds the new cable with these figures, 143 cables in all.
- 18/09/2026 (2.8.1): a sample was added to the list of typical arrangements, a dedicated life safety bracket for the primary supply with FP600 power cables on a heavy-duty ladder and FP500 control cables on a tray above it; the secondary supply is left for a separate route (BS 8519:2020 7.1). BS 8519 is applied when the sample is chosen and every check on it is a pass. The owner ruled the same day that a fire alarm or emergency lighting run beside a life safety run does not raise the 7.3 line, because those installations are subject to BS 5839-1 and BS 5266-1; the tool already worked that way and did not change. The printed report check now prints the sample as well, and once more with its second run changed to the secondary supply, eight cases in all, and measured the text size, page use, repeated sentences and page numbers with no finding. The automated check of the life safety services, the 2,553-bracket enumeration, the 27 random brackets, the 56 hand-calculated checks and the audit checks were re-run on the final build with no difference; the calculations, the wording shown in the tool, the printed report and the exports are unchanged; the served files matched the release and the page was read.
- 18/09/2026 (2.8.0): two services were added to the Service list on a run, Life safety, primary supply and Life safety, secondary supply, for the supplies to life safety and fire-fighting equipment; BS 8519:2020 6.1 recommends a secondary power supply independent of the primary supply. BS 8519 is applied to the bracket when either service is chosen and stays applied while a run serves life safety. The tool now states when the primary and the secondary supplies share one bracket (7.1, diverse cable routes), when life safety cables share a bracket with other services (7.3, a dedicated cable support system) and, for Engineering Toolkit users, when a cable on a life safety run is not a fire-resistant type (clause 11); each line reads the same in the tool, in the printed report and in the report data. Every clause quoted was read in BS 8519:2020, and a new automated check reads them again from the standard on every run. The same check built 144 brackets on 2.7.8 and on 2.8.0, for every earlier service with BS 8519 off and at each category, and found no difference in the wording shown in the tool, the drawing, the printed report or the report data; it compared the figures of a life safety run with those of an Other run on 162 brackets and found them equal, and it fails on the 2.7.8 build. The 2,553-bracket enumeration, the 27 random brackets, the 56 hand-calculated checks, the printed report check and the audit checks were re-run on the final build with no difference; no width, load, reaction or rod value changed for any earlier service; the served files matched the release and the page was read.
- 16/09/2026 (2.7.8): the wording in the tool was revised in plain UK English. The Engineering Toolkit lines and the cable weight tip now say in the tool, and the segregation checks are called checks. The calculations, the printed report and the exports are unchanged. The printed report check on all six presets, the audit checks, the 27 random brackets, the 56 hand-calculated checks and the 2,553-bracket enumeration were re-run on the final build with no difference; the served files matched the release and the page was read.
- 15/09/2026 (2.7.7): the printed report was rearranged to read as a technical report, after the owner's review of a printed 2.7.6 report. The bracket drawing now prints large enough to read: text on the report is 8 pt or larger and the drawing labels 6.8 pt or larger, where some labels printed at 3 to 4 pt on 2.7.6. One summary line names each run that needs action, the run schedule shows a size check and a load check for every run, the basis of the load check is stated once instead of on every run, and a findings table lists the runs that need action and the fire-resistant cable lines. Columns with no entries are left out, the sections after page 1 no longer start on a new page, and every page shows its page number. A new automated check prints the report to PDF for every preset and measures the text size, nearly empty pages, repeated sentences, empty columns and page numbers; it fails on the 2.7.6 build. A second check compared the wording and the drawing in the tool and the report data on 2.7.6 and 2.7.7 and found no difference; the 2,553-bracket enumeration, the 27 random brackets, the 56 hand-calculated checks and the audit checks were re-run on the final build with no difference; no width, load, reaction or rod value changed; the served files matched the release and the page was read.
- 15/09/2026 (2.7.6): the notes written inside the program code were rewritten in plain UK English. The calculations, the wording shown in the tool, the printed report and the exports are unchanged. The 2,553-bracket enumeration and the 27 random brackets were re-run on 2.7.6 with no difference; the served files matched the release and the page was read.
- 15/09/2026 (2.7.5): the emergency lighting lines were read back against BS 5266-1:2025, which replaced the 2016 edition. Its clause 8.2 applies to emergency lighting fed from a central power supply system, so the segregation note and the fire-resistant cable line now say so, the cable line cites 8.2.2, and supply cables to self-contained luminaires are named as needing no fire protection (8.1). The wording in the tool and the notes written inside the program code were revised in plain UK English. A new automated check reads every BS 5266-1 citation and the wording of every program file, in the tool, the printed report and the report data, and fails on the 2.7.4 build; the 2,553-bracket enumeration, the 27 random brackets, the 56 hand-calculated checks and the audit checks were re-run on the final build with no difference; no width, load, reaction or rod value changed; the served files matched the release and the page was read.
- 15/09/2026 (2.7.4): the wording of one line was revised. On a BS 8519 fire route the fire alarm and emergency lighting cable lines now state that the category applies to the supports only, with the drop rods and the containment load checked for the fire survival time; the previous sentence did not say what was checked. The automated check reads the sentence in the tool, the printed report and the report data and fails on the 2.7.3 build; the 2,553-bracket enumeration and the audit checks were re-run on the final build with no difference; no width, load, reaction or rod value changed; the served files matched the release and the page was read.
- 15/09/2026 (2.7.3): changes from the owner's review of a printed 2.7.2 report. On a BS 8519 fire route the fire-resistant cables on each run are now checked in the tool, in the printed report and in the exports alike; before, the only note sat in the design notes shown in the tool. The check was corrected to the standards at the same time: BS 8519:2020 clause 1 excludes the installations covered by BS 5839-1 and BS 5266-1, so fire alarm cables are referred to BS 5839-1:2025 clause 25 and emergency lighting cables to BS 5266-1, and FP200 Gold is treated as the Category 1 control cable its datasheet declares. The segregation reference now cites BS 5839-1:2025 35.5 (26.2 was the 2017 numbering). BS 8519 is switched on from the Standards applied strip, the tier spacing is asked only on a bracket with more than one tier, and the report headline is coloured by the worst verdict. A new automated check reads the fire cable lines in the tool, the printed report and the exports against the scope of the standard and fails on the 2.7.2 build; the 2,553-bracket enumeration, the 27 random brackets and the audit checks were re-run on the final build with no difference; no width, load, reaction or rod value changed; the served files matched the release and the page was read.
- 10/09/2026 (2.7.2): the tier spacing, the BS 8519 fire route and the cable category, read only by a fire-rated or multi-tier bracket, moved into a route options section on the add-a-run panel, closed until opened, so the common run needs only its cables, spare and support spacing. Three wording defects found by the owner on the live tool the same evening are corrected: the over-table bracket advice offered a third rod, which a two-rod trapeze cannot take, and now reads reduce the bracket spacing or split the route; the worst rod tile read over table and now names the rod exceeded; and the indicative load check offered a heavier duty to a heavy-duty tray and a shorter span where no tabulated span was rated for the load, and now names only a remedy that passes on the benchmark rows, or says that none does. An automated check tests all four against the benchmark rows and the live page and fails on the 2.7.1 build; the 2,553-bracket enumeration, the 27 random brackets and the audit checks were re-run on the final build with no difference; no width, load, reaction or rod value changed; the served files matched the release and the page was read. 04/09/2026: a full enumeration drove 2,553 brackets through the live engine, every containment type with single-core, multicore and mixed cable sets in flat and trefoil formation, spaced and touching, with and without spare, at two spans and on unrated and fire-rated routes of every category, plus bunched data runs at four depths, trunking by reference at fifteen sizes, three-run brackets across tier layouts and over-width splits. Every width, load, bracket reaction, rod size and tier count matched a separate calculation of the same method from the same data tables.
- 04/09/2026 (2.7.1): every numeric input was checked for the figure a reader could enter in its place. The custom cable diameter is now defined as the overall diameter over the sheath, not the conductor size; the weight as kilograms per kilometre, with a figure that reads like kilograms per metre flagged in the tool; the support spacing in metres, not the cleat spacing, limited to 12 m and flagged above 6 m; the tier spacing as the clear distance between tray surfaces that Tables 4C4 and 4C5 Note 3 tabulate at 300 mm. No width, load, factor or rod value changed: the 27 random brackets and the audit checks were re-run and all passed, and the script on the live site was confirmed identical to the tested build.
- 03/09/2026 (2.7.0): a check across every PD tool that every printed value is reached through the input the standard derives it from. The grouping factor was found to count every tier on the bracket as a tray of grouped circuits, including data and AV tiers; it now counts only the tiers with loaded circuits and says which, and asks the vertical spacing between tiers that Tables 4C4 and 4C5 Note 3 assume. The loading verdict now names the duty chosen and is an indicative check against the manufacturer's declared SWL, which can be entered. Single-core cables over 40 mm diameter, which Table D1 does not cover, take the tested cleat centres of the basis product or ask for the manufacturer's figure. A perforated or unperforated tray is now a choice, unperforated reading Reference Method C (Table 4A2). Blank spare, blank custom diameter and blank weight ask for the value. The 56 offline checks and the 27 random brackets were re-run and all passed; after upload, the page was read.
- 02/09/2026 (2.6.1): the revised wording was checked in the tool against the house style, using the multi-service bracket preset; no size, load or factor changed. Claims audit 14/07/2026: every cited clause was checked against the standard itself (BS 7671:2018+A4:2026 Tables 4A2, 4C1, 4C4, 4C5; OSG Appendix D Table D1; BS 8519:2020 Annex I and Table E.2; BS EN 61439-1 Table 7; BS EN 61537; BS 5839-1:2017 26.2, now BS 5839-1:2025 35.5; BS 5266-1:2025 8.2.6; BEAMA guide); one grouping factor was corrected to the standard as a result. The 56 hand-calculated checks are re-run offline before every release, and the 03/07/2026 audit figures were reproduced on the live v2 engine on 13/07/2026. Randomised cross-check 15/07/2026: 27 random brackets, including a 12-run, 4-tier case, exactly matched a separate calculation of the same method from the same data tables. Grouping Cg reproduces the Trimble ProDesign worked example. Cable data audit 11/08/2026: all 23 BS 5467 SWA rows were checked row by row against the Eland Cables dimensions tables (Issue 04.0913), and the 3-core 25 mm² was cross-checked against the Doncaster and Cleveland datasheets. Three figures were corrected: the 5-core 10 mm² diameter, 22.09 to 22.9 mm, and the 5-core 70 and 95 mm² rows, which had no published source and now follow the Cleveland Cable BS 5467 datasheet, the only one of the five checked that publishes 5-core above 50 mm². The offline checks were re-run on 12/08/2026 after the interface update and all passed.
Scope and limits
- Tray, ladder and basket runs arranged by tier on one support bracket.
- Power runs are sized single-layer, not by the 45% space factor; data, AV, specialist lighting and ELV runs are sized as a bunched fill (EN 50174-2:2018 basis).
- A trunking on the bracket by reference with an indicative 45% fill check on its nominal W x D; the trunking itself is sized in the Trunking Size Calculator.
- Grouping factors count the tiers with loaded circuits at the vertical tier spacing you enter; below the 300 mm of Tables 4C4/4C5 Note 3 the manufacturer's figure is asked for.
- Perforated tray, ladder and basket read Reference Methods E and F; an unperforated tray reads Method C.
- The load check is indicative against a representative SWL for the duty chosen, or against the manufacturer's SWL where you enter it (BS EN 61537).
What's changedA split run with a spacing between its cables can need fewer or narrower trays, never more. Its grouping factor can change, be printed where 2.22.0 printed none, or not be printed where a tray's circuits go beyond the BS 7671 table. Width remedies with a figure are worked out again and shown only where they pass and no passing check then fails; "move cables to another run" is offered last. With the Engineering Toolkit, the drop rod of a spaced split run can be one size smaller or larger, and load and grouping remedies are worked out again in the same way. With the Toolkit, a split run's load is checked on its heaviest tray with the spare, so the check can now pass where it failed, and a run whose single-core cables have no On-Site Guide Table D1 class is stated as not checked for fault restraint.
- A split run with a spacing between its cables can need fewer or narrower trays, never more. Its grouping factor can change, be printed where 2.22.0 printed none, or not be printed where a tray's circuits go beyond the BS 7671 table. Width remedies with a figure are worked out again and shown only where they pass and no passing check then fails; "move cables to another run" is offered last. With the Engineering Toolkit, the drop rod of a spaced split run can be one size smaller or larger, and load and grouping remedies are worked out again in the same way. With the Toolkit, a split run's load is checked on its heaviest tray with the spare, so the check can now pass where it failed, and a run whose single-core cables have no On-Site Guide Table D1 class is stated as not checked for fault restraint.
- On a split run, cables are now shared by one rule, whatever the order of entry. A circuit entered as more than one cable line can go on different trays. The number of trays, widths, bracket and drop rod loads and grouping factor can differ from 2.21.1. A required width, spare included, that equals a tray width within 0.01 mm now gets that width, which can mean one width narrower or one tray fewer. Unless you enter a containment weight, the makers' widths apply: heavy duty tray starts at 75 mm, ladder at 150 mm, and basket stops at 600 mm, so a wider basket run is now split and its drop rods are sized. On medium and heavy duty tray, cables needing least room by the return flanges now go at the two sides, so some runs need a narrower tray and a few a wider one.
- With PD Cable Database active, nothing changes for you: the calculations, results, wording in the tool, printed report and exports are as in 2.21.0. PD Tray's own copy of the cable list, the cable list address as PD Tray served it and the PD Tray admin page that showed the list are taken out; they were used only while PD Cable Database was not active. The same address is still answered from PD Cable Database. Without PD Cable Database active, no result is shown, as in 2.21.0. No data is removed.
- A listed cable's cores, armour, fire resistance and cable picker group are now read from PD Cable Database. SPLITC-3c35-LSOH, SPLITC-1c35-PVC and STRC-1c35-CNE have none stated: dependent checks, Reference Method included, are not made. In trefoil runs, SPLITC-1c35-PVC and STRC-1c35-CNE are laid flat, so wider or more trays (REVIEW WIDTH or SPLIT) and higher bracket and drop rod loads can result. Cleat spacing on their runs can be wider. With these three, or a Custom single-core cable with armour or fire resistance not answered, the force between conductors and per cleat can be higher. The basis cleat product named can change, or none is named. A warning on the run names cables marked source needed or not in the current datasheet. The perforated tray factor note is re-worded only. A report saved from 2.21.0 lists later cable changes when re-opened. Without the cable list loaded, no result is shown.
- The report's trunking fill item and the trunking width and depth tips no longer call every size nominal: a Custom size section is at its internal size. The report states its Table 4C4 and 4C5 perforated tray factors are for horizontal tray, so a run on vertical tray is not checked by them. Results are unchanged for the same inputs.
- Trunking runs are now checked, and their Utilisation shown, against the 45% space factor with the spare kept free. In the free version and with the Engineering Toolkit, a typed spare of 1 or less is now read as a percentage, so 1 means 1%, not 100%. A re-opened report lists each run size, verdict and bracket changed since saving.
- Runs of over 24 cables with trefoil groups and cables laid flat now have the mixed formation caption and warning. The non-sheathed cable warning quotes the trunking condition of BS 7671 Reg 521.10.1. For unperforated tray, the printed report states how Table 4C4 is read between rows and columns. Widths, grouping factors and verdicts are unchanged for the same inputs.
- The grouping factor (Cg) of multicore runs laid single layer on unperforated tray with more than one tier is now read from BS 7671 Table 4C4; where none can be read, the reason is printed. Re-check those runs. Runs on tray, ladder or basket with protective conductor cables have a note. Widths and verdicts are unchanged for the same inputs.
- On the page for sizing another PD tool's tray runs, runs on tray, ladder or basket with a cable from "Single-core low smoke zero halogen (LSZH) 6491B (trunking runs only, Reg 521.10.1)" are now answered "not worked out". A program fault on one report affects only that report. The free version and widths on PD Tray's own page are unchanged.
- On the page for sizing another PD tool's tray runs, trunking runs and runs set too narrow are now answered "not worked out", with a reason and no width, as are runs whose cables have no diameter, not left out. Each report is answered separately. PD Tray's own page, results for the same inputs and the free version are unchanged.
- Engineering Toolkit printed reports include the brand line once, at the end of the written pages, before the drawing sheets: "UK electrical design. We make the tools and Revit content we use." A page is added for sizing another PD tool's tray runs; no PD tool uses it yet. Results for the same inputs and the free version are unchanged.
- The load check is Engineering Toolkit only. Tier bearers are counted at 2.6 kg/m: re-check drop rods, as one can be a size larger, or exceed M20 and FAIL. FP400, FP500 and FP600 are drawn as armoured and take On-Site Guide Table D1's longer armoured fixing spacings. Indicative safe working loads below 10 kg/m are shown to one decimal place.
- The tool is now PD Tray. Free use is one run at a time, on tier 1. Loads above the 3.0 m indicative safe working load are a FAIL at longer spans. Re-check side by side splits of three or more cable lines, or two single-core lines in trefoil: rod loads can be higher and drop rods one size larger.
- The printed report's top line names every run, and the bracket, needing action in Findings. Fill on the drawing sheets and in the tool includes any flange allowance. Fire-rated Trunking from My Projects takes its internal size. Widths, grouping factors and rods are unchanged for the same inputs; in reports saved before 2.17.1, re-check layouts, entered counts and 0% spares.
- Cables with no diameter or weight, baskets over 600 mm with no self-weight and spans over 3.0 m with no manufacturer's safe working load are not checked. Re-check split runs (lower or no grouping factor, larger rods unless stacked), bunched fills on tray (wider or OVER, rods larger or smaller) and single-core concentric cables (no factor). Cable weights are unchanged.
- The drawing headings read CROSS-SECTION, SECTION and LOADS; the sheet titles read CROSS-SECTION and SECTION. At any spare, including the default 25%, re-check these, which can be wider: medium and heavy duty trays with under 15 mm of width free; trefoil runs with spacing and two single cores left over; and split runs, where a tray could be narrower than its cables. Medium duty trays with 21 to 30 mm cables can be one size smaller, or one tray fewer. With more or fewer trays, a run's Grouping factor (Cg) can change. The cables' kg/m and Reference Method are unchanged.
- Single layer basket runs use wire mesh tray grouping factors, not perforated tray: most rise, three fall by 0.01 (two per basket). No factor is printed for more trays than Table 4C4 or 4C5 lists. With no spare, medium duty tray can now be one size larger where cables over 21 mm would sit under inward flanges. Re-check these cases.
- The Bracket elevation is now called Bracket loading. Grouping factors are no longer printed beyond the limits of BS 7671 Table 4C4 or Table 4C5: re-check cables sized with those factors before 2.14.0. In 2.13.1, the printed Cross-section of the screening room bracket showed rod B's size and "minimum" on separate lines; this is fixed. Otherwise the calculations are unchanged.
- On the drawing sheets, the Notes heading now has more space above it. In the Engineering Toolkit, a printed Notes column that would not fit above the Drawing data is now drawn 10 mm wider. The pictures in the exports show the same changes. The calculations and wording are unchanged in the tool, the printed report and the exports.
- The Bracket elevation is now a drawing sheet, like the cross-section. In the Engineering Toolkit it shows the run loads, rod loads and minimum drop rod size. Both sheets can print at the end of the report and appear in the Word and Excel exports. Before any cable is entered, a drawing marked SAMPLE is shown. The calculations are unchanged.
- The cross-section drawing is now a drawing sheet with callouts, notes, abbreviations and a key. In the Engineering Toolkit, the printed report can include the drawing on its own A4 landscape page with a run schedule. The Word and Excel exports include a picture of that page. The Specialist lighting and grouping lines were reworded. The calculations are unchanged.
- The cable list was moved to PD Cable Database, a separate plugin on projectdesign.io. The cables in the list, the calculations, the wording shown in the tool, the drawings, the printed report and the exports are unchanged. The same list is used, as before, in the Cable Duct, Conduit and Trunking tools, which are not changed in this release.
- A run of loaded circuits laid Bunched is now sized on its single layer width, so its tray can be wider or narrower: re-check trays sized before 2.10.1. Specialist lighting no longer counts as a loaded tier, so other runs on the same bracket can be given a grouping factor up to 0.06 higher, or one where none was printed because of the tier spacing, but no factor above 20 circuits on one tier. A cable not in the cable list is now kept as a Custom cable and named in a check line. Otherwise the calculations are unchanged.
- You can now duplicate runs and move cables between them. Above 20 circuits, a single layer on one tray is now given no grouping factor, as BS 7671 Table 4C1 gives none. Seven FP600 cables now match the current Prysmian FP600s datasheet. Otherwise the calculations are unchanged. Re-check cables sized before 2.9.2 on a run of loaded circuits laid Bunched.
- In the Engineering Toolkit, the printed report now includes the Sizing basis section and again states the safe working load (SWL) each run is checked against, and each run's support system line states its total load. The green, amber and grey are now darker, for the 4.5:1 text contrast that the Web Content Accessibility Guidelines 2.2 require at level AA. The calculations are unchanged.
- A run of loaded circuits with its Lay set to Bunched is now given the grouping factor of BS 7671 Table 4C1 item 1 for the circuits in its bunch; in 2.9.1 it was given a single layer factor, or none. Twelve lines citing a standard now use the verb of the clause they cite. Otherwise the calculations are unchanged.
- The simultaneous overload line now states the tabulated current-carrying capacity It, not Iz. The perforated tray definition is now cited to Appendix 4, 7.2, and the drawing caption and four other lines were corrected. The drawings now have the PD Power Distribution tool's colours and font, and the printed report has the same colours. The calculations are unchanged.
- The panels, buttons and input boxes, apart from the save and export panel, now have the PD Power Distribution tool's colours and font, and the tool name, version and Start again button are in a dark header bar. On a phone the page no longer scrolls sideways. The calculations, the check lines, the printed report and the exports are unchanged.
- The note citing BS 5839-1:2025 35.5 is now shown for fire alarm cables only. On trunking it states the clause's recommendation, a compartment reserved solely for the fire alarm cables; on tray, ladder or basket it states that the clause applies to conduit and trunking only, so a run of their own is good practice, not a requirement. The calculations are unchanged.
- One cable was added to the cable list: FP600S 5-core 35 mm², with an overall diameter of 39 mm and a weight of 3,300 kg/km from the current Prysmian FP600s datasheet. The calculations, the wording shown in the tool, the printed report and the exports are unchanged
- The list of typical arrangements now includes a sample dedicated life safety bracket for the primary supply, with FP600 power cables on a ladder and FP500 control cables on a tray above it. BS 8519 is applied when the sample is chosen, and the secondary supply is left for a separate route (BS 8519:2020 7.1). The calculations are unchanged.
- The Service list now includes "Life safety, primary supply" and "Life safety, secondary supply", and BS 8519 is applied to the bracket when either is chosen. A line in the tool now states when the two supplies share one bracket (BS 8519:2020 7.1) or life safety cables share a bracket with other services (7.3). The results for every other service are unchanged.
- The wording in the tool was revised in plain UK English: the Engineering Toolkit lines and the cable weight tip now say in the tool, and the segregation checks are called checks. The calculations, the printed report and the exports are unchanged
- The printed report is now laid out as a technical report, with text at 8 pt or larger and bracket drawing labels at 6.8 pt or larger. A one-line summary names each run that needs action and why, and every page is numbered. The calculations, the wording and the drawing in the tool, and the exports are unchanged.
- The notes written inside the program code were rewritten in plain UK English. The calculations, the wording shown in the tool, the printed report and the exports are unchanged
- The emergency lighting lines now cite BS 5266-1:2025 and say which wiring they apply to: the partition in shared containment (8.2.6) and the fire-resistant cable selection (8.2.2) apply to luminaires fed from a central power supply system; supply cables to self-contained emergency luminaires need not be fire-protected (8.1). No width, load, factor or rod value changed.
- On a BS 8519 fire route, the fire-resistant cable lines now say plainly what the category applies to on the bracket: the supports only, with the drop rods and the containment load checked for the fire survival time (120 min at Category 3). No width, load, factor or rod value changed
- The standards strip now reads "Standards applied", and its BS 8519 entry is the switch for the fire-rated route. On a BS 8519 route, the fire-resistant cables on every run are checked; fire alarm and emergency lighting cables are selected to BS 5839-1 and BS 5266-1, which BS 8519 does not cover. No width, load, factor or rod value changed.
- The tier spacing and the BS 8519 fire route now sit under Route options on the add-a-run panel. Where the worst rod exceeds the largest tabulated rod, the advice is now to reduce the bracket spacing or split the route: a trapeze bracket has two rods, so a third rod was never the remedy. No load, width or factor changed.
- Every numeric input now names the figure that could be entered by mistake: for example, the weight is kg per kilometre, not kg/m, and the support spacing is in metres, not the cleat spacing in mm. A weight that reads like kg/m and a support spacing above 6 m are flagged. No width, load, factor or rod value changed.
- Only the tiers with loaded circuits are now counted for grouping. The load check now names the duty chosen, or the manufacturer SWL when entered, and is an indicative check, never a compliance verdict. Tray runs now have a perforated or unperforated choice, with Reference Method C printed for unperforated tray. A blank spare, custom OD or weight is now asked for rather than taken as 0.
- The wording was revised in plain UK English: limited to replaces capped at, the manufacturer recommendation applies, the grouping factor line names the factor, and the cable picker labels use plain hyphens and the on-screen text has no dashes. No size or factor changed
- The recommended containment sizes stay in view in a bar that follows you down the page while you edit the runs. Drawing labels have a white background so they read clearly over the cables, and a review flag on a run reads as plain text rather than a dash
- Free use is now measured in sessions: three days of anonymous use, then your email continues free use with no password and no account. The applied grouping factor Cg per run is now free in the tool with its table reference. The report goes by email for free users, with print as part of the Engineering Toolkit.
- Subscriber-facing copy states what the Engineering Toolkit adds rather than what the free preview lacks
- 3-core 10 mm² SWA is now in the cable list, so the 3-core series runs 1.5 to 400 mm²; the 5-core 10, 70 and 95 mm² diameters and weights were corrected to the published dimensions tables
- 3-core 25 mm² SWA is now in the cable list, from the Eland Cables BS 5467 dimensions table
- 6491X PVC and 6491B LSZH singles are now in the cable list, 2.5 to 300 mm², for the CPC that runs with the distribution cables (Reg 521.10.1)
- Bunched runs state their usable depth in the run schedule, in the tool and in the report
- Trunking runs explain where they are included by reference
- The include-drawing tick now controls the printed PDF too, and every printed page gets 12 mm top and bottom margins
- Subscriber PDF prints at one font size and paginates naturally; the one-page squeeze stays on the free preview
- Report wording: BS 8519 reads N/A off a fire route, the stacked-tier note appears only on a stacked split, and a new tick marks the BS EN 61537 verification
- The drop-down list for picking a report from My Projects was widened to fill its row.
- Trunking runs can load a saved Trunking Size Calculator report: the W x D, the cable schedule and the verdict come across (Engineering Toolkit)
- Trunking runs have a 45% space factor fill check (OSG Appendix E), with a fill gauge and an OVER FILL verdict
- Claims audit against the standards: the Table 4C5 factor for 3 spaced trays of 3 circuits corrected from 0.89 to 0.86 (BS 7671 p.474)
- Bracket elevation draws a parallel split as separate trays with the 50 mm gap, matching the cross-section
- Default drop-rod centres now the widest tier plus 50 mm (25 mm clearance each side), so a 50 mm tray defaults to 100 mm centres
- A stacked split counts as real tiers: a bearer under every stacked tray, and both drawings show the stack
- Cross-section tier spacing is measured from the drawn runs, so bunched piles and deep upstands never overlap the tier above.
- Bunched lay for data, AV, specialist lighting and ELV runs (Excel Networking calculator method, EN 50174-2:2018 basis), with a depth input and pile drawing
- 6491B LSZH singles are now in the cable list for trunking runs; non-sheathed singles are not offered on open tray (Reg 521.10.1)
- The Lighting & power and Other services categories were added; the trunking self-weight is optional, with a built-in estimate when blank
- Multi-service redesign: runs arranged on the bracket by tier, with a bracket-wide support check
- Cleat design note covers mixed trays and updates as the fault current is typed
- A cleat-centres elevation was added to the fixing check
- The cable fixing spacings (OSG Table D1) and the BS EN 61914 fault-restraint check were added
- The free PDF was fixed so the page is no longer printed smaller because of the branding.
- BS 7671 grouping (derating) guidance and editable saved reports were added
- A BS 8519 fire-rated cable category advisory was added (FP200 to FP600)
- Rebuilt to BS 7671:2018+A4:2026 with a dynamic reference-method diagram
