Social services have kindly paid for the intercom at my mothers door to be mains powered instead of battery.
The contractor arrived and fitted a 12vac transformer to replace the original 12vac transformer in spite of me telling them many times it needed 12vdc.
You lost me when you said that the contractor was swapping a 12V transformer for a 12V transformer. Was the original transformer battery operated?
The original door bell had a 12VAC transformer but the new intercom door bell
needed a 12VDC power supply and was temporary powered by 2 C type batteries. However the electricians arrived and instead of fitting a new DC power supply replaced the original 12VAC with another 12VAC transformer which clearly did not work. They returned and re-fitted batteries while they got a DC power supply. However there suppliers could not get the CLOSPSU recommended so selected a standard switched mode power supply built into a 13A Plugtop similar to those used to charge a phone. To be fair the recommended one also was a 13A plug in unit.
This is where the problem started as clearly a 13A socket was required to plug it into. This means of course any other item can also be plugged in although with a B6 MCB it would need to be low power.
To begin with I did not think about it but then looked at old transformer and realised it was a Class II device so wondered about the earth connection. However plugging in the ELI tester gave a healthy 0.26 ohms so clearly the earth was connected. Then I looked at the B6 MCB and realised it had not moved. So unlikely it was on the RCD side of the consumer unit. The RCD tester confirmed this to be the case when the RCD failed to trip on all ranges of the tester.
The 12 volt wires were connected with two red crimps a real Heath Robinson affair and the wire left as it was when supplied with a plastic coated wire keeping all the excess cable neat. I want to find a Telephone wire connector box to tidy that up.
The area beside the stairs is handy to store the mobility scooter or electric wheel chair and I had considered using a double adaptor on the new 13A socket. Since there is no RCD protection other than kitchen on sockets I still may use the socket. It would have been so easy to have fitted a RCD socket don't know why they didn't fit one!
I have to try and work out my dad's wiring I am told as I was just one year old when they moved into the new house that there were just 5 sockets. (Dad was proud of it as granddads house only had 2 [15 amp round pin]) I assume therefore all the others are spurs and spurs from spurs so in theory just 5 RCD FCU's should give all sockets RCD protection however also wired in rubber and my son and I want to re-wire. Some cables already pulled in when dad was not looking and with no one living upstairs we can remove floor boards for an extended time. But at the moment sons house has no ceiling and is also being rewired so don't want to start on my mothers house before sons is finished.
However getting a new non protected socket makes me feel one step forward and two steps backwards.
My mother is not the best with new things. I had to go down yesterday as she had pressed button on phone putting answer machine on and she could not then get to phone in time before answer phone cut in. I am worried she would not know how to reset a RCD. She is 88 so have to expect these things. Dad died earlier this year and it's been a busy time.
When the electricians come I have to go down there so for less than £20 to fit a RCD socket is it really worth the time and energy to watch some one else do the work? Quicker to DIY and I never saw any meters so I would assume he does not have any. Mine may not be calibrated but I have got them and they do work.
