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 β 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 3Β consumer units on TT systems,Β 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 β This is not to the current editionβ¨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 β regulation says, βWiring systems in escape routes shall be supported such that they will not be liable to premature collapse in the event of a fire.β
5. How long between inspections on a domestic property?
This is at the inspectorβs discretion. The guidance is a period of 10 years or on a change of ownership/tenancy. Itβs in a landlordβs 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 electricianβs work off?
Yes β 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.
