Trailing edge dimmers

[Nigel52]

my sparky has installed a four gang dimmer set up as follows.
1. Covering 17 x 6w leds
2 covering 9 x 6w leds
3. Covering 3 x 9w leds
4. Covering a few under counter LEDs.

We are constantly blowing LEDs on dimmer 1 and I think it is totally overloaded. The only solution I can think of is to replace dimmer 1 with a push button on/off module that would fit in the same plate as dimmer one module.

Btw all four dimmer switches are on a single chrome plate.

Any other ideas?

 

[kerching]

What are the dimmers rated at?
What does your electrician say?
Too many lamps usually toasts dimmers, not the other way around.
What make are the lamps and dimmers?

 

[Nigel52]

What are the dimmers rated at?
What does your electrician say?
Too many lamps usually toasts dimmers, not the other way around.
What make are the lamps and dimmers?

From new fitted with Osram 4.5w 2700k however, he suggested changing to Belns Melbs 4.9w 2700k which certainly don’t blow so often. Since day 1 we have had to keep the dimmer on full to stop the LEDs constantly flickering. Before one blews you get a flickering on the faulty one and then one or two others.
As regards the dimmer loading, I’m not sure. I thought they were either 300w or 400w.

Obviously now I’ve looked at the LEDs in more detail my original post said 6w and should have been 4.5w.

 

[monkey5]

Decent dimmable LED lamps and a decent dimmer for LEDs (vpro) should be smoth and not flicker at all, sound like something not compatible. Are the lamps defo dimmable? What makes the dimmer?

 

[Murdoch]

17 leds on 1 dimmer was a bit optimist imho

 

[Nigel52]

Decent dimmable LED lamps and a decent dimmer for LEDs (vpro) should be smoth and not flicker at all, sound like something not compatible. Are the lamps defo dimmable? What makes the dimmer?

Yes, both makes of LEDs are dimmable. Don’t know the make of the dimmer.

According to various Google searches when using LEDs the maximum output should be 10% of the dimmer rating ie 400w = 40 watts etc. Hence my thinking 17x 4.9w of 83.3w is too high.

 

[binky]

Incompatible dimmer and lamps at a rough guess. If you get a compatible set of gear, then it will dim smoothly. Rexel do their own brand versions of vpro and osram lamps, I've found these work really well together.

 

[Murdoch]

But you need to consider the start up current of LEDs - often much more than the running current

 

[johnb2713]

But you need to consider the start up current of LEDs - often much more than the running current

Yep, about 100 x the running current but only for 1 M/Sec, it shouldn't cause any significant issues. I have 30 x 5w LED lights in my office, on a 250w dimmer and they have not been an issue at all.

 

[monkey5]

Varilight do vpro dimmers for 10, 20 and 30 leds

 

[monkey5]

I'd check the dimmer brand, I've had BG ones that are LED compatible but are rubbish,

 

[Murdoch]

Yep, about 100 x the running current but only for 1 M/Sec, it shouldn't cause any significant issues. I have 30 x 5w LED lights in my office, on a 25ow dimmer and they have not been an issue at all.

back in the real world start up current on led lights can be a problem

 

[binky]

back in the real world start up current on led lights can be a problem

I've installed kWs of led lighting on a church. I fitted type C breakers, concerned about in rush currents, but when you look at the data, it's so short a time period MCBs shouldn't be bothered by it.

 

[johnb2713]

back in the real world start up current on led lights can be a problem

Not in my 'real world' experience but I'm sure you must have witnessed it somewhere. Most modern drivers and dimmers have softstart anyway to avoid the issue completely.

 

[johnb2713]

I've installed kWs of led lighting on a church. I fitted type C breakers, concerned about in rush currents, but when you look at the data, it's so short a time period MCBs shouldn't be bothered by it.

That looks good Mr Binky!

 

[binky]

That looks good Mr Binky!

It was an interesting job. The church was bombed during WW2, so has been left as a war memorial. We got invaded by anti nuclear protestors one morning, 6 middle aged ladies managed to cover the fence and church in banners in a couple if hours before we got there, took the council staff all day to remove them.... The lads did a deal with the ladies, use of the portaloo in return for cake, and staying out of the way whilst they worked. Having got the lights in, we were testing them one evening, and a little old fella crossed the road to have a look with his missus. So they were the first people to visit the church bombed by the Luftwaffa with its new lights, and they were German - you couldn't make it up!

I decided to avoid public works after that

 

[binky]

there was quite a few more banners than this

 

[johnb2713]

there was quite a few more banners than this

Jeez, crazy people around. Crazy protesters, this sort of response is predictable.......

 

[binky]

they were fine, it was just not what I wanted on a Monday morning. Still, it's given me a good story to tell

 

[Andy1733]

Remove a handful of bulbs (ooops lamps) and see if the problem persists.