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How much load can a lighting circuit take?

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As per the thread title. I’m looking to add an electric hoist to my loft and it’s rated at 500 watts. Can I take a feed from the lighting circuit to run this?
 
Well you probably CAN as modern lamps on a lighting circuit are generally LED, at around just 3 watts each or so.
Traditionally a lighting circuit was supposed to take 1200 watts (college days). And also people would stick a 500 watt floodlight on a lighting circuit.
So, I would say a loose yes - if there's no alternative.

This hoist. If the lighting circuit was fail, and cause darkness, would there be any danger for anyone who was using the hoist?
 
As per the thread title. I’m looking to add an electric hoist to my loft and it’s rated at 500 watts. Can I take a feed from the lighting circuit to run this?

It should be fine, but there is a slight risk on start up of the motor, it might trip the 6amp MCB. Try it and see, and if all OK, you could add a 13amp socket for the lift, to the lighting circuit - if the hoist is fitted with a plug.
 
It should be fine, but there is a slight risk on start up of the motor, it might trip the 6amp MCB. Try it and see, and if all OK, you could add a 13amp socket for the lift, to the lighting circuit - if the hoist is fitted with a plug.
Could maybe change to a type C if that happened, depending on Zs?
 
The maximum supply to a lighting circuit is 16 amp, but most lighting circuits have something somewhere which is rated 5 or 6 amp, so in the main 6 amp is the limit.

Lighting circuits are limited to 3% volt drop, where other circuits are allowed 5% so in theory you should measure the line - neutral loop impedance or prospective short circuit current, at both origin and at the place where the load will be, and calculate the volt drop.

This is from an old book, but it says
314.1 Every installation shall be divided into circuits, as necessary, to:
(i) avoid hazards and minimize inconvenience in the event of a fault
(ii) facilitate safe inspection, testing and maintenance (see also Section 537)
(iii) take account of danger that may arise from the failure of a single circuit such as a lighting circuit
(iv) reduce the possibility of unwanted tripping of RCDs due to excessive protective conductor currents produced by equipment in normal operation
(v) mitigate the effects of electromagnetic interferences (EMI)
(vi) prevent the indirect energizing of a circuit intended to be isolated.
If you feel that will be complied with, then not a problem.

Likely as with aerial amplifiers and bathroom extractors having the odd item on the lighting circuit is unlikely to cause a problem, but you have to decide if you feel it will comply. Your writing out the minor works certificate not me.
 
Likely as with aerial amplifiers and bathroom extractors having the odd item on the lighting circuit is unlikely to cause a problem, but you have to decide if you feel it will comply. Your writing out the minor works certificate not me.
Back in the day of incandescent bulbs (and the day when no-one denied that there were 'bulbs' :-) ), I'm sure it was not unusual to have 500 W worth of bulbs on a lighting circuit, with sometimes all of them 'on' simultaneously. Indeed, in my house I have one room which has a total of 18 candle bulbs (in multiple 'chandelier-like'fittings. Back in the day, that was 18 x 25 W - aka 450 W, for just one room!
 
Back in the day of incandescent bulbs (and the day when no-one denied that there were 'bulbs' :) ), I'm sure it was not unusual to have 500 W worth of bulbs on a lighting circuit, with sometimes all of them 'on' simultaneously. Indeed, in my house I have one room which has a total of 18 candle bulbs (in multiple 'chandelier-like'fittings. Back in the day, that was 18 x 25 W - aka 450 W, for just one room!
Come to think of it, we have 8 down-lights in our kitchen. We used to have 8 x 50w bulbs in them. In addition. We had another 20 x 10w bulbs in/on/under the cabinets. That’s 600w in total. They’ve all since been replaced with LED's now because I was fed up changing them - I used to buy them in bulk!
 
Come to think of it, we have 8 down-lights in our kitchen. We used to have 8 x 50w bulbs in them. In addition. We had another 20 x 10w bulbs in/on/under the cabinets. That’s 600w in total.
Indeed. Slightly worse' than my room I described, then!
They’ve all since been replaced with LED's now because I was fed up changing them - I used to buy them in bulk!
Same here. Mine is a very large house with a good few multi-bulb/lamp fittings - which I think tots up to a total of around 80 lamps/bulbs. 'Back then', replacing dead one was a tedious weekly, if not daily, task and, like you, I used to buy large batches of them every 2-3 months. Now that everything is LED, I buy a handful every year or two!
 
I’ve never had to replace one LED yet.
As one would expect with the 80 or so I have here, I've had to replace just a few over the years (even though I always buy 'the cheapest I can find' these days!), but very few. As I wrote, I now only buy a small handful every year or two!
 
I’ve never had to replace one LED yet.

I've had to replace the same one twice, and a second one twice, which I put down to the electronics over-heating. One was an exterior lantern fitting, which had no ventilation at all, I added some, and it's been fine since. The other was two wall-lights, where the lamp holder was uppermost, with a glass shade trapping the rising heat. Both lamps failed, within a week of each other. I inverted the fittings, so they were open at the top, and they have been fine since.

The thing with LED's is, they may not generate much heat, but what little they do produce they, need to be able to easily disperse it.
 
I’ve never had to replace one LED yet.

You are really lucky. I have worked in many houses where the LEDs failed faster than a halogen would have failed. That said, they were probably cheap bulbs.
 
You are really lucky. I have worked in many houses where the LEDs failed faster than a halogen would have failed. That said, they were probably cheap bulbs.

More likely, they suffered inadequate means of disposing of the heat generated.
 
I have a problem with LED g9 bulbs not lasting very long, and they are in an open bare exposed bulb situation similar to this fitting. Most of the house are GU10 LEDs
lightture.JPG
 

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