Cable Design Review

A cable manufacturer’s submittal package is where the risk sits. The calculations arrive as a PDF with a cover sheet, the numbers are rarely shown, and the assumptions behind them almost never are. We review the package line by line against the standards it claims to follow, and return a numbered sheet with a comment, a status and a required action against every item.

When You Need It

  • · A manufacturer or installer has issued cable calculations and drawings for approval and you need them checked before you sign them off
  • · You are the developer or owner and the EPC holds the design, so nobody independent has read it
  • · A type test report has been offered as covering a cable that is not quite the cable being installed
  • · You need a defensible record of what was queried and when, for the project file

Standards Applied

IEC 60840IEC 60287IEC 60949CIGRE TB 889CIGRE TB 347ENA ER C55

The report states the clause and the edition it works to, so the calculation can be reproduced by whoever reviews it.

What You Get

A numbered review sheet: document reference, comment, status, supporting document and action required, for every item
A written position on each calculation, saying whether the method and the inputs are defensible, not just whether the answer looks reasonable
Installation parameters extracted and confirmed: minimum bending radius during installation and installed, maximum pulling tension, roller contact force, sidewall pressure
A short covering note listing the items that must be closed before construction, separated from the ones that can be carried

Worth knowing what this catches. On a 132 kV project we found a pulling study that had applied a copper allowable stress to an aluminium conductor: 60 N/mm² on 1000 mm², against a datasheet limit of 40 kN and a CIGRE TB 889 default for aluminium of 30 N/mm². Fifty per cent over the manufacturer’s own limit, and double the CIGRE default. On the same package the KEMA type test report covered a 1600 mm² copper cable while the cable being installed was 1000 mm² aluminium, offered as the same construction family.

Frequently Asked Questions

Do you review drawings as well as calculations?

Yes. Route layouts, trench sections, joint bay and sealing end arrangements, bonding line diagrams and duct and chamber details, alongside the calculations they depend on. A calculation that assumes a trench arrangement the drawings do not show is a finding in itself.

Can you carry the review through the revisions?

Yes, and most packages come back more than once. We close the actions out as revisions arrive and keep the register current, so there is one document that says what is still open. That is a review that stays live rather than an appointment. We do not attend site, witness tests or certify milestones, which is what an owner’s engineer does.

Will you review a package you did not design?

That is the usual case, and it is the point. The review is worth more when it is independent of whoever produced the design.

The Rest of the Cable Chain

Review, calculation, drawings, testing and fault location, from one place. See the whole picture.

Cable Sizing and Current Rating

Cyclic and Emergency Ratings

Short Circuit and Screen Sizing

Induced Voltage and Bonding

Thermo-mechanical and Fault Forces

EMF Assessment

Cable Pulling Calculations

Route Design and Drawings

Testing and Fault Location

Request a Cable Sizing Study

A free calculator answers one question at standard conditions. A study takes the actual route, burial depth, soil resistivity, grouping and load profile, and gives you a signed report you can issue to the DNO or the client. We take single calculations as readily as full cable system designs.

Or call 07951 651 013 or email enquiries@stardeltapower.co.uk