Outsourced cable sizing and protection studies using Trimble ProDesign — the software many contractors still know as Amtech ProDesign.
We produce cable sizing calculations and protection coordination studies for electrical contractors and consultancies that don't have an in-house Trimble ProDesign (formerly Amtech ProDesign) licence or designer. You send us the design information; we return a submission-ready, BS 7671-compliant calculation pack — typically within days, not weeks.
ProDesign and Trimble PowerNet are accepted across UK infrastructure programmes including rail, aviation and energy projects, as well as commercial and industrial buildings. Every calculation is verified against BS 7671 and the relevant sector standards.
A compliant cable calculation is more than picking a size from a table. For every circuit we check current-carrying capacity with the correct installation method and grouping factors, voltage drop across the whole network, earth fault loop impedance against disconnection times, and the adiabatic (thermal withstand) requirement for fault conditions. ProDesign models the complete distribution network, so a change at the supply end automatically re-validates every downstream circuit — the errors that slip through spreadsheet calculations don't survive here.
We produce protection coordination studies with time–current curves showing discrimination between upstream and downstream devices, fault level calculations to BS EN 60909 (3-phase and single-phase), and short-circuit protection verification. For HV systems and larger networks we use Trimble PowerNet for load flow and network analysis.
Electrical contractors pricing or delivering design-and-build work without a ProDesign licence, consultancies needing overflow calculation capacity, and project teams needing an existing Amtech/ProDesign model updated. Typical applications include underground rail and station LV distribution, airport terminal and airside systems, EHV cable system supporting calculations, and commercial, industrial and mixed-use buildings.
Cable and fault level calculations often feed directly into earthing design — see our earthing study design service, read our guide to cable sizing to BS 7671: spreadsheets vs ProDesign, or check typical calculation pack prices.
Common questions from contractors about outsourcing ProDesign calculations.
Yes. Amtech ProDesign became Trimble ProDesign after Trimble acquired Amtech, and the software many contractors still call "Amtech" is the same calculation engine. If your client specification asks for Amtech calculations, a Trimble ProDesign calculation pack satisfies it.
Typically a single-line diagram or schematic, the load schedule, cable routes and lengths (or a marked-up layout drawing), the supply characteristics (fault level and earthing arrangement), and any client specification. If something is missing we tell you up front rather than guessing.
Yes. We can pick up existing ProDesign project files, update or extend the network model, and re-issue the calculations — useful for design changes, construction-stage amendments, or completing a design someone else started.
A single distribution board is usually a few working days. A full building or multi-board network typically takes one to two weeks depending on size and how complete the input information is. We confirm a delivery date before starting.
Yes. Every pack is verified against BS 7671:2018+A2:2022 and presented with source data, software outputs and a results summary — the format principal contractors, consultants and approval authorities expect for design submissions.