Earth fault

[luem]

I have a house on an estate of 8 houses in Cyprus. The houses are modern and the electrics a good standard. The electricity to the houses is supplied alternately on 2 of the phases, the 3rd phase being reserved for street lighting. Each house has a box outside in which is the meter, 80amp fuse and a 63 amp DP isolator switch. Inside the house is a consumer unit housing the MCBs and a 63 amp RCCD (all Hager). My RCCD trips out for no apparent reason, at random times. The wiring from the CU onwards has been checked and there is no earth fault. I think the cause is an earth fault in one of the houses on the same phase. Could this be so? (I'm not an electrician!!) If it is, could I safely replace the RCCD with a 63 amp DP isolator switch? I have one outside socket and that is in an IP56 enclosure with an RCCD built in.

 

[pushrod]

Thanks Engineer,

I'm in UK at the moment. I don't recall seeing an earth lead in the meter box, so probably an earth rod. Do you know of a good spark on our side?

Just out of interest where are you in the TRNC - i usually spend a couple of weeks in Yesiltepe (towards Alsancak) in the summer - mind i don't pack all my tools

 

[oldtimer]

You are doing the right thing disconnecting your appliainces one thing to highlight though the appliances that can cause it is washing machines, dishwashers etc but one thing you did not mention was do you have a pool and if so the pumps that feeds it could have problems so if this is the case swith the pump off for a day and if no trips then Dos San Maguels Porv vavor or is that in another coumtry then !!

Mind you my other half has always wanted to go to cyprus I wonder if customs will let me take my trusty 1553 ?

 

[luem]

Another thought, ....You could do away with your 300mA RCD device, and replace your MCBs with 30mA RCBOs of the same rating as the MCBs being replaced. This can be a little expensive, depends on how many breakers you have in your CU. They will make your installation far more secure, as only the circuit that has a fault will trip, NOT the whole installation as you have right now... Here i can buy them at around 9 Euros a piece. Worth thinking about and a good investment in the short and long term...

Thanks for that, you're really helpful. I was thinking along the same lines ie. RCBO. It's a 10 way, ranging from 6, 16 and 32 amp. If I put RCBOs on, could I replace the RCCD with a 63 amp DP isolator. Where can I get them in the South for 9 euros? Will they fit on the Hager Din rail?

 

[luem]

Just out of interest where are you in the TRNC - i usually spend a couple of weeks in Yesiltepe (towards Alsancak) in the summer - mind i don't pack all my tools

Thanks Pushrod. My house is in Karsiyaka, just along the road. I'm out on 4 May for 2 months

 

[luem]

You are doing the right thing disconnecting your appliainces one thing to highlight though the appliances that can cause it is washing machines, dishwashers etc but one thing you did not mention was do you have a pool and if so the pumps that feeds it could have problems so if this is the case swith the pump off for a day and if no trips then Dos San Maguels Porv vavor or is that in another coumtry then !!

Mind you my other half has always wanted to go to cyprus I wonder if customs will let me take my trusty 1553 ?[/QUOTE ]

Thanks Oldtimer. I do have a pool, on its own circuit 32amp MCB in CU. The spark went into the pool room to test the pump but he didn't check anything in the cabinet in the pool room ie. contactor, timer etc. The problem is I have an outside pump for the water supply, a well pump (submersible in the well) and a pump for the garden irigation system. These are all spurred off the 32 amp ring main. I suppose RCBOs is the best route as otherwise "needle in haystack" springs to mind!!

 

[luem]

I just want to say this to everyone - I've only just joined this forum and I am absolutely amazed at the helpful replies you have all posted. It is indeed very refreshing and reassuring to find such caring people.
Thank you all!!

 

[Engineer54]

Thanks for that, you're really helpful. I was thinking along the same lines ie. RCBO. It's a 10 way, ranging from 6, 16 and 32 amp. If I put RCBOs on, could I replace the RCCD with a 63 amp DP isolator. Where can I get them in the South for 9 euros? Will they fit on the Hager Din rail?

Yes Luem, that is exactly what you would do when removing the RCCD. As far as i am aware , all MCBS/RCBOs are Din Rail fitted. I'm not aware either, that, Din Rails sizes in CU/DB's are any different from one manufacturer to another!! You can purchase the RCBOs at around this price in most of the so-called wholesalers....

 

[luem]

Yes Luem, that is exactly what you would do when removing the RCCD. As far as i am aware , all MCBS/RCBOs are Din Rail fitted. I'm not aware either, that, Din Rails sizes in CU/DB's are any different from one manufacturer to another!! You can purchase the RCBOs at around this price in most of the so-called wholesalers....

Can you give me the address or phone nos of wholesalers in the south?

Also I got my figure wrong earlier. I said 300mA, but shouldn't it be 30mA?

 

[Engineer54]

Deep submersible Well pumps are notorious for supply cord problems. When these pumps kick in, the cords can, and quite often are dragged against the well bore sides, eventually wearing the sheath and insulation down to the conductor cores. Every so often get a neighbour to give you a hand to pull the pump up from the well in order for you to inspect the motor supply cord for any damage. If caught in time, amalgamating electrical tape can effect a lasting repair, if damage has not penetrated the conductors insulation....

 

[pushrod]

Hey luem is it just one rcd protecting all 10 mcbs? The 63A rating on the rcd is the max current it can safely take. I have come across boards where you add up the mcbs and you get something like a theoretical max of 160+Amps all being protected by one 63A rcd. Now in reality you don't get that max current but it can be enough current to cook the rcd so that it becomes a bit random. Swapping a new one in fixed it. Mind when i have done it i tested the rcd and knew it was that before changing it. However, for about £20 you can get a replacement and swap it over and you might just be lucky and have sorted it - if it doesn't you have a spare. If you do try this be very careful about safe isolation first.

BTW i do vaguely know Karsiyaka, been through it a couple of times when coming down from the end of the mountain top road where the ruined tank is or from Kozan? - looked nice.

 

[pushrod]

Can you give me the address or phone nos of wholesalers in the south?

Also I got my figure wrong earlier. I said 300mA, but shouldn't it be 30mA?

yep should be 30mA.

 

[luem]

Deep submersible Well pumps are notorious for supply cord problems. When these pumps kick in, the cords can, and quite often are dragged against the well bore sides, eventually wearing the sheath and insulation down to the conductor cores. Every so often get a neighbour to give you a hand to pull the pump up from the well in order for you to inspect the motor supply cord for any damage. If caught in time, amalgamating electrical tape can effect a lasting repair, if damage has not penetrated the conductors insulation....

Thanks for that, good advice

 

[luem]

Thanks for that Pushrod. I had heard that the RCD can get flaky. How could I test it to find out.

You're right about Karsiyaka; we're on the seaside of the main road.

 

[Engineer54]

Can you give me the address or phone nos of wholesalers in the south?

Also I got my figure wrong earlier. I said 300mA, but shouldn't it be 30mA?

I don't normally call these wholesalers i just go in person, ....most make out the can't speak English on the phone , but strangely can when you turn up there ..... and can see your money!!! lol!!!

Depends, i had a 500mA front end RCCD originally, Now all changed to RCBOs. Seen a few 300mA over here too, but never a front end 30mA .... I would say 99% of all houses and villas here, have a 500mA front ender. Check when you back in May as to the exact value of your device. As i say, no matter what, you are going to be far better off converting your 10 way CU, ...Front enders are, ...and always have been a real pain in the rear!!! ..lol!!!

 

[luem]

I don't normally call these wholesalers i just go in person, ....most make out the can't speak English on the phone , but strangely can when you turn up there ..... and can see your money!!! lol!!!

Depends, i had a 500mA front end RCCD originally, Now all changed to RCBOs. Seen a few 300mA over here too, but never a front end 30mA .... I would say 99% of all houses and villas here, have a 500mA front ender. Check when you back in May as to the exact value of your device. As i say, no matter what, you are going to be far better off converting your 10 way CU, ...Front enders are, ...and always have been a real pain in the rear!!! ..lol!!!

What's a front ender? and shouldn't they be 30mA? What do you mean by value of device? Remeber I'm not a spark, just a thick lawyer!!!
Just realized what you mean - yes I think the RCCD is rated at 300 milliamp, it's a Hager