RCDs tripping at several properties

[Russell Dawson]

Hi, I'm a resident at a Park Home site (glorified caravans) with about 50 houses. On Saturday a.m. my fuse box RCD tripped out but only for the sockets. I assumed that I was at fault and proceeded to isolate appliances to find the culprit. That afternoon it went again. At that time I became aware that several (11) of my neighbours were having the same problem. It has continued to trip on about 15 other occasions over the ensuing days. There is no pattern to it. The houses are scattered around the site. It happens at the same time for each house. It only affects the socket circuit. We've had professionals on site who go around scratching their heads. What is going on? Has anybody had a similar experience? It must be an outside influence in my view. I have suggested that the boxes in the houses may be of a similar make and perhaps slightly more sensitive to a spike but that was dismissed out of hand. Any clues?

 

[Russell Dawson]

I expect the 11 concerned are on a different phase than the other 28 homes, sounds a bit heath robinson this whole matter

Yes, but it's been OK for 9 years. The odd glitch but nothing out of the ordinary like this. Some matters are very HR but we always thought that this had been done right/professionally. OMG, I'd better get the gas checked! Cheers

 

[Midwest]

Is your plot rented, or free or leasehold?

 

[telectrix]

i'd first of all determine if all the affected properties were on the same phase. if so, then a supply fault on that phase would need to get DNO involved.

 

[Pete999]

i'd first of all determine if all the affected properties were on the same phase. if so, then a supply fault on that phase would need to get DNO involved.

Agree

 

[Russell Dawson]

i'd first of all determine if all the affected properties were on the same phase. if so, then a supply fault on that phase would need to get DNO involved.

I don't think they are from what I've overheard. Appreciate suggestion. Thanks.

 

[Midwest]

i'd first of all determine if all the affected properties were on the same phase. if so, then a supply fault on that phase would need to get DNO involved.

Wilko beat you to it, calling DNO #7

Could of clicked old, but that would of been childish.

 

[Octopus]

but the pro and site owners don't seem able to do that at the moment.

Jack of all trades, master of none probably

Such installations are highly unlikely to employ permanently a decent spark, nor bring one in at additional expense to their "handy man"

Just saying

 

[snowhead]

I'd be looking at the Neutral (loose) in the 3 phase db , (if it is 3ph), or upstream switch fuse (if any) or meter or DNO head.

 

[johnduffell]

Unfortunately, our RCD testers only measure how quickly they trip, not if they trip too quick

That's not true, the 1/2 dI setting ensures that it doesn't trip at all within the timeout of the tester. If tested at 1x dI there's no lower limit on tripping time.

 

[Russell Dawson]

Problem appears to have been resolved. One of the homes NOT affected has admitted that he has had a problem over the past few days with a socket that has a short. He has repeatedly tried it and reset when tripped. The timings have been checked and match. It still shouldn't happen though, that is, other houses having their RCDs tripping. Very strange. Thanks to all for input.

 

[stevels4]

No theories on this then guys?

 

[Wilko]

Only guess really - but to trip the adjoining installation RCD implies the fault current is seen over there too, implies local earth not working?

 

[johnduffell]

how about this for a theory, not really 100% convincing, but ... the fault on another phase would pull that phase and the neutral closer together. Even with similar impedances i.e. no loose neutral, on N and that L (call it L1), the N would move away from L2 and L3. I.e. an overvoltage on those phases.
This overvoltage would last until the fault protection kicks in on the faulty circuit, which could be up to 0.4s for a socket circuit.
If that overvoltage causes extra leakage somehow, the RCDs would trip on the other phases.

If it's not TN-C-S then this could all apply to the installation earths instead.

 

[sham]

Problem appears to have been resolved. One of the homes NOT affected has admitted that he has had a problem over the past few days with a socket that has a short. He has repeatedly tried it and reset when tripped. The timings have been checked and match. It still shouldn't happen though, that is, other houses having their RCDs tripping. Very strange. Thanks to all for input.

Thank you for letting us know, and have to say, I was kind of right.

 

[bigspark17]

Static vans do not usually have hook ups, they are hard wired into a supply from a meter in a building around 20-30 mtrs max from the static and the DB in the van is where the trips are, hook ups are for tourers not fixed statics, that said I do not doubt there are statics somewhere connected to a hook up, and as Tel said a lot of supplies to the meters and switches feeding the vans are PME, well around here anyhow.

Dont know how this comment should be aloud to stay on forum, have you ever worked on any static caravans cos ur talking complete bs!!