RCD Tripping and Surge protection devices

[SIMBO]

Has anyone come across surge protection devices being the source of an RCD trip at consumer unit ?

 

[davelerave]

not particularly

but apparently they can be a nuisance-downstream of rcds

what type of SPD? if it's a multilead spd -can you swop it out to confirm?

if it's in the DB i assume it should be 'upstream'

 

[Deleted member 9648]

Yep...known them to cause or at least contribute to nuisance tripping, mainly when several SP leads are in use on a system with a 30ma RCD main switch ,after removal (of the leads)things improved somewhat,and no other obvious causes found.
They are often the cause of low IR readings if you miss them,typically around 0.3Mohm.

 

[SIMBO]

Yes is multilead spd. Will swop for non spd lead and hope that dont get surge damage nor trip!

 

[BEN5637]

Have seen this numerous times, def a point to note on ring main faults.

 

[Gordie]

yes I have a couple of years ago it seems they can cause nuisence tripping, but I had one for my computer and I did not have any problems so I cannot say for sure.

 

[malcolmsanford]

Surge protection devices do trip RCDs as they regulate transient voltages and RCDs are voltage sensative.

The class I SPD device is normally the one fitted at the origin of the installtion and is for protection against direct lightning strikes.

Class II are normally at sub board level and used for transient voltage surges on indirect lightning strikes, motors flourescent fittings, and equipment that have transient switching loads.

Class III are the very local ones used at individual pieces of equipment or on extension leads.

Most installtions that require SPD use a combination of devices and they are mostly class I and II which would be upstram of RCD protection.

Unfortunately what happens with the class III in the UK is when you get brown outs, or even switching on the distribution network it will cause the SPD to intiate and of course it will unbalance the RCD causing it to trip

 

[stephanjs]

Surge protection devices do trip RCDs as they regulate transient voltages and RCDs are voltage sensative.

The class I SPD device is normally the one fitted at the origin of the installtion and is for protection against direct lightning strikes.

Class II are normally at sub board level and used for transient voltage surges on indirect lightning strikes, motors flourescent fittings, and equipment that have transient switching loads.

Class III are the very local ones used at individual pieces of equipment or on extension leads.

Most installtions that require SPD use a combination of devices and they are mostly class I and II which would be upstram of RCD protection.

Unfortunately what happens with the class III in the UK is when you get brown outs, or even switching on the distribution network it will cause the SPD to intiate and of course it will unbalance the RCD causing it to trip

What is a "brown out"?

 

[netblindpaul]

Surge protection devices do trip RCDs as they regulate transient voltages and RCDs are voltage sensative.

The class I SPD device is normally the one fitted at the origin of the installtion and is for protection against direct lightning strikes.

Class II are normally at sub board level and used for transient voltage surges on indirect lightning strikes, motors flourescent fittings, and equipment that have transient switching loads.

Class III are the very local ones used at individual pieces of equipment or on extension leads.

Most installtions that require SPD use a combination of devices and they are mostly class I and II which would be upstram of RCD protection.

Unfortunately what happens with the class III in the UK is when you get brown outs, or even switching on the distribution network it will cause the SPD to intiate and of course it will unbalance the RCD causing it to trip

Malcolm,
No SPD will protect against a direct strike, they are not designed to protect against direct strikes, even origin spurge protective devices are only designed to protect against man made and naturally induced transients to a level well below the energy of a direct strike.

HTH.

 

[Chr!s]

Malcolm,
No SPD will protect against a direct strike, they are not designed to protect against direct strikes, even origin spurge protective devices are only designed to protect against man made and naturally induced transients to a level well below the energy of a direct strike.

HTH.

Their are Transient protectors specifically design to protect against Lightning transients.

Regards Chris

 

[MarkieSparkie]

What is a "brown out"?

The sort of accident you have when close to a lightening strike.:joker:

Seriously, it's American slang for a dip or sag in the supply voltage below that of normal supply regulation.