Stroma Certification reveals some of the most frequently asked questions tackled by its technical support team.
1. I have recently completed the installation of an outbuilding of a house, the supply cable was existing however I have installed two new circuits and a new consumer unit. Do I need to notify this job?
Yes – Section 2.2 of Part P clearly states Part P applies to electrical installations that are in outbuildings such as shed detached garages and domestic greenhouses (2.2.a.ii).
2. Regarding the installation of metal clad Amendment 3 consumer units on TT systems, what requirements must be met?
If a dual RCD consumer unit is to be used, the meter tails entering the unit must be clamped to prevent the cables from moving, the main switch must be a 100mA time delayed (s type) RCCB then the 2 30mA RCDs protecting each circuit. Alternatively a Main Switch could be used if each circuit is protected by an individual 30mA RCBO.
3. When conducting a condition report, if the consumer unit is made of a non-combustible material, is the installation now un-satisfactory?
No – This is not to the current edition of BS7671 and therefore a code 3 would be raised for this particular deviation. As long as there are no further deviations a satisfactory assessment would still be possible.
4. I have installed some plastic conduit as containment in a fire exit but I have installed steel saddles to fasten it to the wall and ceiling. Is this compliant?
Yes – regulation says, “Wiring systems in escape routes shall be supported such that they will not be liable to premature collapse in the event of a fire.”
5. How long between inspections on a domestic property?
This is at the inspector’s discretion. The guidance is a period of 10 years or on a change of ownership/tenancy. It’s in a landlord’s best interest to do this as tenant may have changed faceplates or added additional points in an un-safe way.
6. Can I sign another electrician’s work off?
Yes – but only if you are registered with a recognised CPS third party scheme. The criteria, however, is not as simple as merely testing a completed installation that has already been energised. A 100% inspection of the installation must be completed at first fix stage, then a 100% inspection at second fix stage before you test and energise the installation yourself before issuing a third party installation certificate.
