I may be being a bit thick, but ...
... how do I know if my SPD is still functioning?
The same might be said of an RCD, but of course we all check them six monthly so we could check the little indicator in the SPD at the same time.
However, if the RCD has tripped, we know about it 'cos the lights go off. If the SPD has exceeded its useful life, we know nothing. The one which I shall be installing at home has a switch for an indicator or buzzer, but that wouldn't be much use for a CU at the back of the hall cupboard/under the stairs/in the garage.
I am left thinking that if SPDs should be fitted, there should also be an effective alarm system. Do you agree?
