led floodlight problems

[Guest154]

hi having some problems with led floodlight , firstly had 17 140w led floodlights on one circuit wired with a 10mm single line swa , started with 16 amp mcb and it kept tripping on start up not every time , tested all the cabling and and put the clamp meter on it cuming up with just over 10 amps on start up , so i changed the mcb to a 20 amp still tripping then a 32 still tripping finally a 40 amp mcb and it has stopped tripping , i then used the same floodlights on another 2 jobs 1 with 4 on a circuit and the other with 12 on a circuit and the same thing happened had to keep uppin the mcb , they are not cheap fittings £400 a piece , i did contact the company that make them but the say they have had no issues like this b4 , anyone have any ideas

 

[SKY]

Why 10mm cable? is it a very very long length?
I guess you have a cable fault somewhere or water ingress.

 

[telectrix]

have you tried using a C type breaker?

 

[Guest154]

about 60 metres long , it was incase the leds were no good , would change the fittings to M-H fittings , yes even tryed a type d mcb , but there doesnt seem to be a high start up current

 

[Guest154]

it cant be a cable fault on all 3 circuits

 

[ian.settle1]

Why 10mm cable? is it a very very long length?
I guess you have a cable fault somewhere or water ingress.

10mm for a 10A load?

As said how longer length of run is it?

Sounds like a trapped cable or water ingress as suggested you need to check you fittings and switches

 

[Octopus]

Is it the RCD going or the MCB. If its the MCB its quite likely that the "start up" current of the LED lights is taking more than the MCB can handle. As tel suggests can you try a type c?

 

[Guest154]

done all that , this is happening on 3 seperate circuits on 3 different locations

 

[dan86]

I would be checking for water ingress first. Especially with the weather we have just now!

 

[Guest154]

clamp meter is only showing just over 10 amps on start up

 

[Guest154]

fittings are Celsian 2 140W dimond Floodlights

 

[Octopus]

fittings are Celsian 2 140W dimond Floodlights

Speak to the maunfacturer?

 

[lister101]

Trying to get my head around this, not sure i'm right!
For simplicity you would need to look at the 4 floodlight setup. If this can trip at 32A C MCB which has a 0.1S trip at between 10 & 20 times the rated current i.e 320A minimum you are looking at 80A start up current per lamp! You said you used single line SWA, did you use this on all the problem installations? Personally I would do a mock up installation with several lamps & do some careful fault finding.

 

[dan86]

you say you have the same issue on 3 sites, but have a different number of lights at each, and have had to up the mcb.
so what size mcb and swa are you using on each currently?

 

[Octopus]

Not sure if it was on here or another forum but I recently read an interesting thread on LED start up currents