To aid those carrying out testing, a number of manufacturers of devices employing the 0.25 A characteristic are now providing an advisory label explaining this which can be affixed inside the lid of the consumer unit or distribution board in which the RCD is installed.

PD IEC/TR 62350:2006 Guidance for the correct use of residual current-operated protective devices (RCDs) for household and similar use.Connected with this subject is Section 551 Low Voltage Generator Sets. As a PV system is a generating set usually operating in parallel with the normal electrical supply, Regulation 551.7 refers.

The verification of the effectiveness of the measures applied for additional protection is fulfilled by visual inspection and testing. Where RCDs are required for additional protection, the effectiveness of automatic disconnection of supply by RCD’s shall be verified using suitable test equipment according to BS EN 61557-6 (see Regulations 643.1) to confirm that the relevant requirements of Chapter 41 are met. RCD tests may be affected by loads downstream that contain electronic equipment or may incorporate permanent leakage current due to the capacitance of cables where circuit lengths are considerable.This applies to the RCD test label, periodic test label, presence of SPD label (new requirement). The only exception is the warning notice of additional supplies which, if required, will still need to be present on the enclosure.