URGENT HELP PLEASE. Compact florescent lamps & RCBOs

[jedisparks]

Hi to all

Ive got a small problem on a job that ive just about finished and ready to handover.

Background; bed & breakfast chalets with compact florescent recessed spot lights protected by Protek RCBOs.

baisically on one of these lighting circuits the RCBO (actually its a Protek SRCBO) keeps tripping when i switch on the bathroom pullcord. It dosent happen every time, i can turn them on and off a few times and then randomly it will knock the RCBO off, but always on the action of either switching on or off the pullcord. Weird!

There are 4 x 11watt CFL recessed lights controlled by this switch. I have tested for IR and all is clear. I have checked all connections and all is clear. I have replaced the pullcord switch too.

This is leading me to think that there maybe some incompatabilty between the CFLs and the RCBO which is 6amp type B by the way.

Has anyone come across a problem like this? or have any suggestions? I need to fix this quick as the chalets already have bookings for next week.

Many Thanks in advance

 

[needasparks]

Could it just be a faulty lamp going overcurrent on start. for only 4 lamps its just as cheap to change them all to get the right one first.

 

[BlueToBits]

I assume it happens with multiple chalets.
It could be a switch on surge from the transformers in the lamps. If I may suggest:
remove the RCCB and replace with a type B MCB and see if the problem persists.
If so, replace the RCCB with a type C.

 

[telectrix]

possibly try a type c. if it's overcurrent.

 

[needasparks]

Mind you protek is a bit happy shopper, could just be a faulty rcbo, if you've done IR it can't be anything else really.

 

[needasparks]

I assume it happens with multiple chalets.
It could be a switch on surge from the transformers in the lamps. If I may suggest:
remove the RCCB and replace with a type B MCB and see if the problem persists.
If so, replace the RCCB with a type C.

good point, i missed more than one chalet bit.

 

[telectrix]

good point, i missed more than one chalet bit.

no, he said it was on 1 circuit. i assumed just 1 chalet was affected. if it's all chelets, i would suggest cumulative leakage on the cfl's . answer would be to fit LEDs. or proper lamps.

 

[jedisparks]

Wow thanks so far

Sorry i havent got back sooner, i had to make the tea!

right i need to give you a bit more info; I dont know how relevant this is but the chalet affected has its lighting circuit on an SRCBO rather than an RCBO like the others. Until this job i didnt know they existed. Im asuming the "S" just means small because it is around the same physical size as an MCB, just a bit bigger, unlike most RCBOs which are quite long/tall.

Maybe this type of SRCBO has slightly different tripping characteristics...or maybe it is faulty..

Also included on the same circuit is an extractor fan, another 8 CFL recessed lights in the bedroom and 1 NM emergency light. But it only seems to trip when i switch the bathroom pullcord and again its only occasionally/randomly but in the instant that i switch on or off the pullcord. All other chalets are fine.

This is a strange one. Im well within the current capacity of the breaker, no low IR readings, connections are sound. My gut feeling is to try swapping this SRCBO for one of the other RCBOs or to try a type c.

Many thanks for your inputs. I loved the happy shopper comment but im not sure its relevant, i think even the more established companys have alot to answer for regarding quality of parts; have you seen the current Wylex excuse for an MCB lately?

 

[davelerave]

are they the same cfl lights in the bedroom

i'd be thinking 'el cheapo' rcbo anyhow- i think protek is dodgy

 

[jedisparks]

yup same cfls in the bedroom. I like to think reasonably priced! and that dosent explain why im not having problems with the others!

 

[davelerave]

so did you swap 4 from bedroom into bathroom?

and see what happens

 

[rocker]

Surely the 's' signifies time delayed RCD? Which I wouldn't use on normal lighting circuit anyway.

 

[davelerave]

think so

 

[rocker]

Back to the problem, though, is it possible you have a borrowed neutral? Also, have you checked the way it's been wired, have had this problem with lights being connected to CPC rather than neutral.

Try putting a normal bulb in and see what happens.

 

[davelerave]

hmm
going by what he said-this is happening when he switches on and off lights

so suspect 'rogue' bulb or 'cheapo' rcbo

unless the drink is confusing me again

 

[telectrix]

start with swapping the srcbo.

 

[jedisparks]

Thanks again

Ah yes i could try swapping 4 bulbs form the bedroom into the bathroom - good idea that, I think ill do that 1st I can also try normal bulbs too, they are GU10 so i can try some halogen bulbs definately.

Its not time delayed its just smaller in physical size than any rcbo ive seen. I asked for rcbos and noticed that some of them turned out to be these SRCBOs which i havent seen before, didnt think anything of it and put them in, anyway the others are for the shower circuits and they seem fine.

Great replies & much appreciated thanks

 

[rocker]

hmm
going by what he said-this is happening when he switches on and off lights

so suspect 'rogue' bulb or 'cheapo' rcbo

unless the drink is confusing me again

Yep a light fitting with it's neutral wired to the earth by mistake would cause this problem..... if you turn it on, the thing trips, then you reset the RCBO, does the light then work? Cos if it does, this could (not necessarily) be the problem. Though try changing the bulbs and the RCBO.