A primary substation on the northern outskirts of Peterborough was undergoing a major refurbishment, with switchgear, transformers and protection all being replaced. As part of the works, four 33kV feeder circuits needed re-pulling on slightly altered cable routes and re-jointing into the new switchgear bays.
The DNO ran a competitive tender for the cabling element — we won on programme certainty and 33kV jointing capacity.
What the job involved
- Four 33kV cables (300mm² triplex) pulled drum-to-drum across new and existing duct.
- Six straight joints in pre-cast pits under DNO supervision.
- Indoor terminations into the new GIS switchgear bays.
- VLF, PD and sheath testing across all four circuits.
- Liaison with switchgear OEM commissioning team daily.
Key challenges
- Shared shutdown window with other primary works — cable team had to flex around switchgear and transformer teams.
- One pull crossed a live LV cable run — section hand-dug to verify before machine excavation.
- April weather variable — joints built inside tented enclosures.
Outcome
- All four circuits tested clean first time.
- Substation re-energised on schedule.
- DNO confirmed the team for two further primary site refurbs in the region.
Big primary refurb has a lot of moving parts. Their cable crew slotted in with the switchgear and transformer teams without anyone needing to be a referee.
— DNO Project Manager, Peterborough, Cambridgeshire
Need something similar?
If you're planning a cable pulling job across North London or the Home Counties — talk to us about scope, sequencing and a price. We work directly with DNOs, ICPs, main contractors and developers.