Rccd Tripping

[pjelec]

I have rewired a small internet shop. I have tested all circuits with an Insulation Resistance Tester. I have >999 reading on all circuits.
About twice a day the RCCD trips out.

He has 3 Surge Protector leads which the computers are connected to. When I test the Protectors L-E & N-E my readings are 000 which means is a really low reading.

This could be the cause of the RCCD tripping out but surely the protectors dont cause this.
Spoken to the Manufacturer but got no help at all.

Do not want to risk removing the protectors as the computers could get damaged.

Hope someone can help

 

[pevvers]

it's preferable to omit it -if rules allow

Which they would if you were to use non-standard sockets, as this would make them straight away not for general use by ordinary persons, which is what the wording is for sockets requiring additional protection by 30mA RCD in reg 411.3.3 of BS7671:2008.

Like this -

 

[DjSparkos]

All good suggestions. Your post didnt fall on deaf ears.....

 

[pevvers]

Ah good, I'm glad!

 

[pjelec]

There are 10 PCs in the shop fed from 3 seperate circuits. Each circuit has a surge porotector connected to the end. The Circuits are protected with 1 RCCD in the fuseboard. I now think with the info off here that there are too many computers running through the RCCD

How many PCs are on the same RCD?

 

[High Tower]

Have you configured the earths to be high integrity

 

[pjelec]

I have an Individual CPC to each circuit. The circuits are wired in plastic tube using singles cable. The 3 circuits are wired as radials on 16amp Circuit breakers.

Have you configured the earths to be high integrity

 

[ian.settle1]

I aggre with High Tower! Switch Mode PS's in Pc's usually have aprox 3.5ma leakage. I wouldn't want to have more than 5 pc's on a 30ma RCD. How many PC's in the cafe

10 PCs on 3 seperate circuits with 1 30mA RCCD protecting the whole lot will trip as 10 x 3.5 = 35mA

 

[High Tower]

I have an Individual CPC to each circuit. The circuits are wired in plastic tube using singles cable. The 3 circuits are wired as radials on 16amp Circuit breakers.

Are the legs of the ring cpc segregated in the earth bar and are the socket faces suitable for HI earth?? ie can eaths be segregated on socket ??

 

[pevvers]

I think the question has to be whether this installation has worked correctly for years with these PC's on it or whether it's a new installation that has obviously not been designed correctly. If it's the former then I would be looking at the surge protection devices, if it's the latter then I would look to be splitting the circuits onto RCBO's with a max of 5 PC's on each... Or omitting RCD protection by using the aforementioned non-standard sockets.

The high integrity earthing is definitely something that should be looked into and considered if the circuit is to be altered, but wouldn't change the current problem of the tripping RCD.

 

[pjelec]

The Earths are connected to the earth bar seperately but the sockets only have 1 earth terminal

Are the legs of the ring cpc segregated in the earth bar and are the socket faces suitable for HI earth?? ie can eaths be segregated on socket ??

 

[pjelec]

The shop has had problems for about 2 years since he opened. He used the existing electrics in the shop from the previous tenant. It can trip twice a day or not trip for a week. We rewired the shop 6 months ago and the problem was still the same. We only rewired it as it was in such a state. We then replaced the surge protectors and still no different.
3 months ago he had a flood and all computers were damaged, now they are all new.

I think the question has to be whether this installation has worked correctly for years with these PC's on it or whether it's a new installation that has obviously not been designed correctly. If it's the former then I would be looking at the surge protection devices, if it's the latter then I would look to be splitting the circuits onto RCBO's with a max of 5 PC's on each... Or omitting RCD protection by using the aforementioned non-standard sockets.

The high integrity earthing is definitely something that should be looked into and considered if the circuit is to be altered, but wouldn't change the current problem of the tripping RCD.

 

[pevvers]

I would say that it is not designed for all that IT equipment then, and would need splitting as previously suggested onto RCBO's if you so deem the sockets to be additional protected by 30mA RCD...

The fact that it trips every now and again would suggest different usage of the PC's, maybe when more are on or some are being heavily used.

 

[lemau]

hello.....i think RCCD is enough to protect your pc..because no device can prevent the lightning power...

 

[pevvers]

hello.....i think RCCD is enough to protect your pc..because no device can prevent the lightning power...

Apart from surge protective devices of course...

 

[antimatter]

Individual SCRD's for each PC, a little pricey but may stop the tripping.

Anyone know whether a time delayed RCD would be alowed in this circumstance or not?