Problems with electric tripping at night.

[Dande]

Hi everyone,

Basically I moved house last July and we have had random problems with the electric tripping for most of that time I think. But it seems to be getting worse and it is always between like 7pm and 10pm.

It's housing association and it looks like a new consumer unit was fitted just before we moved in. The kitchen sockets tripped for a while but apparently it was because of faulty electrics from the boiler. We are still waiting for that to be fixed. We thought something from the kitchen could trip the other group of sockets but that's not possible is it? Because it has its own rcd? It's just that when the tumble dryer or washing machine is on it seems to do it more.

The upstairs and downstairs sockets are grouped together so there is more to rule out as a culprit. Does it definitely have to be an appliance or could there be a fault with the house wiring?

The only other thing I have done is change 2 double sockets for 2 that have 2 additional usb ports.

I tried unplugging a lot of stuff but it still tripped. I will keep trying. Is there anything else I can test or do to help myself?

Sorry for rambling on, I am just trying to give as much info as possible.

 

[333rocky333]

A fault on a house wiring circuit, can sometimes not become evident until a high electric consuming device is used on a faultless other circuit.
So it is possible the washing machine although ok, creates enough load on the system to show up a fault elsewhere, though it still could be the appliance causing trip at a certain stage of its cycle

 

[oldbutnotdead]

First job is to put the original sockets back instead of your USB things. Presumably you are renting (you said housing association)- tampering with the electrical installation could be a breach of your tenancy agreement.
Second thing is to unplug stuff when you're not using it (don't just switch it off, many 13A sockets only switch the live)- this should help you to narrow down the possible list of culprits
Washing machine, tumble dryer, kettle, outside lights are common sources of random RCD trips- they all have water and electricity in close proximity.
When the HA turn up to fix the boiler, if it's an electrician they send ask him to PAT your appliances (a bung would be in order as well as tea and biccies)- that'll give you some clues

 

[ericmark]

Both @333rocky333 and @oldbutnotdead have made good points, a RCD does not measure current to earth but in imbalance between power out and power in and assumes if not the same must be going to earth.

It seems likely the fault is not line to earth but neutral to earth, and with no load neutral and earth are the same voltage so no current flows, as the load increases so the voltage between neutral and earth also increases, until there is enough pressure to allow the 15 - 30 mA to flow which trips the RCD.

With a insulation tester the electrician can likely find the fault, and part of a PAT test includes insulation tests, but in the mean time unplug anything not in use, as switches are normally only on the line not the neutral.

I had it with daughters house, it was one of the screws on a socket had crushed the insulation on the neutral causing intermittent connection to earth, it took some finding, so swapping sockets could cause the fault.

 

[bernardgreen]

This is why a Neutral to Earth fault can be very difficult to locate. The RCD trips even though the MCB for the faulty circuit has been switched OFF.

To locate the fault it is necessary to do insulation resistance measurements with the Neutrals disconnected from the Neutral bar in the consumer unit.

 

[Taylortwocities]

@Dande
You said there was a boiler fault. How have you isolated the boiler from the electric supply?

 

[Dande]

A fault on a house wiring circuit, can sometimes not become evident until a high electric consuming device is used on a faultless other circuit.
So it is possible the washing machine although ok, creates enough load on the system to show up a fault elsewhere, though it still could be the appliance causing trip at a certain stage of its cycle

Ok thanks. Can a problem with something on the kitchen circuit affect another group like the upstairs/downstairs sockets?

First job is to put the original sockets back instead of your USB things. Presumably you are renting (you said housing association)- tampering with the electrical installation could be a breach of your tenancy agreement.
Second thing is to unplug stuff when you're not using it (don't just switch it off, many 13A sockets only switch the live)- this should help you to narrow down the possible list of culprits
Washing machine, tumble dryer, kettle, outside lights are common sources of random RCD trips- they all have water and electricity in close proximity.
When the HA turn up to fix the boiler, if it's an electrician they send ask him to PAT your appliances (a bung would be in order as well as tea and biccies)- that'll give you some clues

Ok that makes sense. Thanks. I am going to pull the washing machine out and check for water leaks. Could a problem in the kitchen or boiler trip the downstairs/upstairs sockets switch though? I am not sure what the boiler is grouped with? That's what it feels like is happening. They fixed the faulty pump on the boiler but it is giving an electrical fault code now so they are sending an electrician. When we put the heating on it trips the electric almost every time but not always straight away.

Both @333rocky333 and @oldbutnotdead have made good points, a RCD does not measure current to earth but in imbalance between power out and power in and assumes if not the same must be going to earth.

It seems likely the fault is not line to earth but neutral to earth, and with no load neutral and earth are the same voltage so no current flows, as the load increases so the voltage between neutral and earth also increases, until there is enough pressure to allow the 15 - 30 mA to flow which trips the RCD.

With a insulation tester the electrician can likely find the fault, and part of a PAT test includes insulation tests, but in the mean time unplug anything not in use, as switches are normally only on the line not the neutral.

I had it with daughters house, it was one of the screws on a socket had crushed the insulation on the neutral causing intermittent connection to earth, it took some finding, so swapping sockets could cause the fault.

Ok thanks, that's great info. I will look at the plug sockets tomorrow. I felt like I did a good job with them but I am not an electrician obviously so I will check them.

@Dande
You said there was a boiler fault. How have you isolated the boiler from the electric supply?

They came to change the pump on the boiler which was definitely faulty but now it is giving an electrical fault code. I can't have the heating on or hot water or it seems to trip more often. We haven't had hot water for 2 months because they are taking there time to fix it.

The only thing I have done is switch the boiler off at the switch next to it. Is there another way because I guess it's hardwired? Is the boiler normally on the kitchen rcd or can it be with the upstairs/downstairs sockets rcd?

 

[Dande]

Also I just remembered that I took the doorbell off to replace with a wireless one. I just tucked the wires behind just in the hole. Could that cause any issues? Should I have capped them off?

I think it was all disconnected when they changed the consumer unit and I can't see a box on the wall inside anywhere to do with the doorbell. Well I don't know what I would be looking for.
There is some sort of box on the other side of the wall to the consumer unit.

Also the smoke alarms keep doing weird stuff like a high pitched constant noise for 30 seconds like it's running out of battery or something but they are hardwired. Just trying to rule everything out.

 

[Taylortwocities]

Perhaps the smoke alarms are telling you that the power is switched off?

 

[Dande]

Perhaps the smoke alarms are telling you that the power is switched off?

I am not allowed to touch them as I am renting but the light flashes on them. They just randomly go off when they shouldn't. They were new when they did the consumer unit by the looks of it. I told them and they said I would have to wait 3 months for an appointment to fix them. I bought some battery powered smoke alarms so that I can turn off the rcd for the smoke alarms to rule it out as a culprit.

 

[Taylortwocities]

Then, if you are renting
1. You should not have been installing USB sockets
And
2. Any problems with the electrical installation is the responsibility of the HA, not you.

 

[sparkymarka]

I would name and shame the HA …..No Hot water for 2 months ….and 3 months to get your smoke alarms sorted ….if your paying rent I would stop until these are sorted …

 

[Dande]

Then, if you are renting
1. You should not have been installing USB sockets
And
2. Any problems with the electrical installation is the responsibility of the HA, not you.

Yes I am aware of all that, It was already mentioned above. I didn't know that before I changed them and they have been changed back already, Loads of people do it whether it's right or wrong. I am more capable than most and have worked in the building trade for over 20 years so I am not an idiot. I was just trying to make my home better as it was such a ****hole.

Edited to add that I just spoke to them and they said it's fine to change sockets and light fittings/switches as long as they are changed back to the original when moving out.

I would name and shame the HA …..No Hot water for 2 months ….and 3 months to get your smoke alarms sorted ….if your paying rent I would stop until these are sorted …

Yeah thanks mate, I have raised a complaint with them but I have to go through the official process first before I can escalate it. The electrician is coming round on the 11th so I am keeping my fingers crossed for a a fix. If not then they wont get rent this month as I pay it all myself.

 

[conny]

If you have young children/grandchildren living with you, (i.e. with the HA's knowledge), or someone who is disabled you should be made a high priority response tenant and receive service ASAP, which usually means within 5 days for standard things which don't materially affect your lifestyle. However, such things as faulty electrics/no heat/water are treated as emergencies and should be dealt with as quickly as possible.

 

[Dande]

If you have young children/grandchildren living with you, (i.e. with the HA's knowledge), or someone who is disabled you should be made a high priority response tenant and receive service ASAP, which usually means within 5 days for standard things which don't materially affect your lifestyle. However, such things as faulty electrics/no heat/water are treated as emergencies and should be dealt with as quickly as possible.

Thanks very much for the info. I think I need to tell them this and make myself clear.