Spur from lighting cct

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KillerWatt

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I've asked my boss this question and even he isn't sure LOL

Anyway, is it still legal to spur off a lighting circuit to run a shower pump?

The pump itself will draw no more than 1.9A, so my plan (because it's easy) is to connect the booster pump to an RCD protected spur fitted with a 3A fuse, which is subsequently fed from the downstairs lighting circuit (non RCD protected).

Getting a feed from the CU, or stabbing in to a ring isn't really feasible.

Anybody see any problems with that from a legal standpoint?

PS

The spur itself is going to be situated in the master bedroom, as that is the other side of the stud wall which seperates the bathroom.

 
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no problem at all if all the lighting loads add up

i've done same thing on an upstairs lighting circuit, pump in loft, 3A fused spur, only had 4lights upstairs and wired in 1.5mm so at a push mcb could have been upgraded

 
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A motor start up current for 1.9A load could possibly trip 5/6 amp circuit breaker probably not but as my signiture says better to be safe than sorry. Also lighting circuits are prone to not be earthed I have to put them right regularly due to bad wiring. As said this is only my opinion and most instructions for these pumps state should be connected to a power circuit so if anything goes wrong would the warranty be valid.

Batty

 
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If it was the only way I probably would do it but only if it was the only way.Batty
I am in the Batty agreement club on this one! ;) :x

I personally wouldn't put a shower pump off a lighting circuit! :(

I am reasonably confident a shower pump takes a lot more than an extractor fan, & associated start-up surges could cause later problems?? :(

What do the manufactures instructions say?? ?:| ? :|

 

KillerWatt

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What do the manufactures instructions say?? ?:| ? :|
They say sod all.

The specs say the motor will draw a "maximum" of 1.9A, whether the start up surge is included in this figure I do not know.

I guess the easiest way to find out if it will trip the breaker when it starts is to try it. If it works, then it works - If it doesn't, then it looks like I'm having a moderate amount of floorboards up.

Regarding earthing, the lighting circuit is fully earthed (this place is 10 years old) so I'm not worried on that score.

Loading wise, there are only 6 fittings on the downstairs lighting cct and even if they were all switched on at the same time (which they will never be) the load would not exceed 300W - so theres plenty of room from a loading point of view.

Thanks for all the responses folks.

 

paulh

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I think sometimes you have to work with what you can get. I personally would not like to do it but that don't make it wrong or that I wouldn't do it either. I would clearly label the lighting cct at the cu and the spur so no confusion can arise.

 

sparkyork

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i say go for it, stick it on the lighting circuit. the ammount of socket circuits ive seen with no earths etc as well not just lighting, do the job, test it then thats it. Just cos you have a 32a ringmain the are often at certain times of the day maxed out anyway, think if you got one ring main in a house with a plug in oven, kettle going, toaster on, electric heating etc etc.

its all reletive, maybe not ideal off the lighting circuit but you have assesed the job and given it some thought, you are breaking no laws no regs no FA, opinions are just opinions.

 

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