LED GU10 lighting max number per circuit , circuit design, dimmers

[lazy username]

Hello everyone,
lately alot of customers have been asking to change there standard 50watt lv halogen spotlights for the more energy efficient LED gu10's.
My question is... is there a max number of these that can be on a circuit?

Previously the rule of thumb was 10 but with the loads considerably lower has this changed??

Obviously mcbs will have to be changed to suit the load and dimmers will have to be changed to the TRIAC or SCR type.

Also when first fixing should I design my circuits (except protective devices at DB)for 50w gu10 halogens incase the customer decides when Ive left that he is not happy with the light he is getting from his leds and decides to change them back or gets the wrong replacement when one blows ??

Apologies for my ignorance but Ive been out of work and back in college for awhile, Im still catching up with changes to the regs

 

[Darkwood]

Dont get me wrong, i see and can agree in part with both sides of the argument but yes until 50w hals are discontinued and prob 5yrs have passed for old stock sales then its to be done this way, so looking at possibly 2020 before we can relax this one, only a new lamp holder designed specifically to accept a new LED lamp range will get round this quicker

 

[Farmelectrics]

Well even if they changed LEDs back to 50w halogens the circuit would only be pulling 2kw it's wired in 1.5mm so you could up the breaker to 10amp what's the problem with that

 

[Farmelectrics]

Are we saying the most gu10 we have on 6 amp circuit is 14

 

[keniff]

I'd have to say 50w per fitting and taking into account the 6 amp mcb will protect the cable, I would be more than comfortable fitting more than 14?

 

[Strima]

Without taking into account any inrush current you could in theory get away with 27 50W GU10 on a 6A MCB.

Using a 10A MCB you could get up to 46 lamps on a circuit. Both these calculations are right on the operating current of the OCPD.

Or my maths could be way out... :lol:

 

[Farmelectrics]

Sorry Keith done my sums wrong long day ha 21 50w halogens = 1.1kw =about 4.5 amp so why can you only have 14 on a circuit

 

[keniff]

Lol I know the feeling! Long day

 

[Darkwood]

Limitations are due to the DC drivers inrush currents on led lamps irrespective of the FLC and as i mentioned before its down to manufactures guide of the lamps or mcb guides, as well as taking into account with gu10's that it can be interchanged with a 50w hal', its also good to give allowances in design for sizing of dimmers etc so if large room it should be taken in to account that dimmers may be requested, well i say should but i mean good practice, i no longer put switch boxes in too but 25mm as a minimum, its done me well in customer relations so far.

 

[kingeri]

And what about diversity....on a domestic lighting it's 66%, which allows us to fit more. This, however, is not always ideal as I know plenty of folks who have a busy house and may well have all the lights on at once!