Source 4 Mini LED

[Bryson]

I think I might have a genuine use for a couple of Source 4 Mini LEDs. The one thing is, I need it to dim properly. I'm looking to replace a couple of minuettes that do a shot onto my stage access steps and are always in the way.

 

Has anyone got one? Does it dim nicely?

[ocfe]

PM sent.

[Tomo]

2-wire dimmable LED simply doesn't dim fully - ever. (It's effectively impossible.)

For "proper" theatrical dimming of LED you need hot power and a control signal, or DC drivers which is effectively the same thing.

 

There's a published dimming performance summary here:

http://www.etcconnect.com/Support/Articles/Source-Four-Mini-LED-Dimming-Performance.aspx

 

It's about 20% to full.

 

The tungsten variety dims perfectly of course.

Edited October 11, 2015 by Tomo

[gyro_gearloose]

Or you could dim it mechanically, like everyone has had to do for years with discharge lamps. I don't know much about dimmable high power LED drivers, but I imagine that the electronics to control a couple of stepper motors for some dimming shutters is much simpler than an LED driver.

[timsabre]

Or you could dim it mechanically, like everyone has had to do for years with discharge lamps. I don't know much about dimmable high power LED drivers, but I imagine that the electronics to control a couple of stepper motors for some dimming shutters is much simpler than an LED driver.

 

It's physically big though. Hard to fit in a S4 mini.

A mains-dimming LED driver, which works out the dim level by measuring the cutoff point on the mains waveform, is fairly simple in concept. In real life it's hard because the mains waveform is often badly distorted and a lot of mains dimmers are rubbish and can't handle a very small very capacitive load.

[GreatBigHippy]

I have just gone through this with 12 of them I bought.

With the transformer they come with on a standard dimmer with no dummy load, nope, they do not dim nicely, they barely dim at all.

With a 500w flood on the same channel, yeah, I got them working, but it is horrible and pointless.

So, I have just spent the best part of a week wiring up these dimmers,

EldoLED

And they work perfectly. I am currently using them in an animation studio and they hold a perfect steady beam down to about 5%.

I bought mine through Light Dimensions who were good enough to set them up with the correct current ratings etc.

Send me a PM with an e-mail if you want pics of my set up.

[timsabre]

Those aren't dimmers, they are LED drivers. What are you controlling them from just out of interest, DMX?

[alistermorton]

One of the ETC staff at Plasa did say that they are developing a "proper" supply for the S4 mini which will take hard power and DMX and do proper smooth 0-100 dimming and it is due to be announced RSN.

[timsabre]

edit: sorry... duplicate post Edited October 12, 2015 by timsabre

[GreatBigHippy]

Those aren't dimmers, they are LED drivers. What are you controlling them from just out of interest, DMX?

Sorry yes, terminology wrong.

But, yes, DMX driven.

[timsabre]

Those aren't dimmers, they are LED drivers. What are you controlling them from just out of interest, DMX?

Sorry yes, terminology wrong.

But, yes, DMX driven.

 

Should dim smoothly to 0% if it's DMX. What Tomo was saying applied to mains-dimmable drivers (which is presumably what you had before)

[GreatBigHippy]

Oh, I wasn't replying to Tomo, I was replying to the OP.

 

ETCs published performance details IIRC were based on using ETC dimmers. My results were based on using alphapacks, which is what we had, and they didn't work. Flickering all over the place unless it was at full or 0%.

 

The last 5% dimming I believe (again IIRC) is because the driver switches to a different way of dimming. It's just a touch steppy and snaps a little at the end, nothing too rough, but maybe not perfect for theatre?

 

Anyways, it's been a bit of a faff but for the job I am doing they have worked perfectly.

[timsabre]

ETCs published performance details IIRC were based on using ETC dimmers. My results were based on using alphapacks, which is what we had, and they didn't work. Flickering all over the place unless it was at full or 0%.

 

This is my experience with mains dimmable LED on all triac dimmers I have tried, and I've tried most of the professional brands. The problem is the triacs latch on due to the capacitive load rather than switching when they are meant to.

Trailing edge (IGBT) dimmers work much better, I think ETC do have a type of IGBT dimmer so maybe that is what they used to test. But you still can't dim below about 20%.

Edited October 12, 2015 by timsabre

[gyro_gearloose]

Or you could dim it mechanically, like everyone has had to do for years with discharge lamps. I don't know much about dimmable high power LED drivers, but I imagine that the electronics to control a couple of stepper motors for some dimming shutters is much simpler than an LED driver.

 

It's physically big though. Hard to fit in a S4 mini.

A mains-dimming LED driver, which works out the dim level by measuring the cutoff point on the mains waveform, is fairly simple in concept. In real life it's hard because the mains waveform is often badly distorted and a lot of mains dimmers are rubbish and can't handle a very small very capacitive load.

Sure, it would be a bit of a squeeze, but at least it would be guaranteed to work from 0-100%. I've seen irises used as dimmers in discharge lamps, and yes, it does work, and doesn't do the usual 'shrinking beam' effect you usually get from an iris. One of those might be easier to fit inside the round body of a Source 4. It would just need to positioned in the right place so that it works as a dimmer and not an iris.

[jmdh]

I have just gone through this with 12 of them I bought.

With the transformer they come with on a standard dimmer with no dummy load, nope, they do not dim nicely, they barely dim at all.

With a 500w flood on the same channel, yeah, I got them working, but it is horrible and pointless.

So, I have just spent the best part of a week wiring up these dimmers,

EldoLED

And they work perfectly. I am currently using them in an animation studio and they hold a perfect steady beam down to about 5%.

I bought mine through Light Dimensions who were good enough to set them up with the correct current ratings etc.

Send me a PM with an e-mail if you want pics of my set up.

 

... 5 years later.

 

So, I read that ETC were planning a proper DMX controlled driver for these, but it doesn't seem to have materialised. So I'm looking at doing something similar to you - how hard is the mod (I'd quite like to retain the possibility of using the built in driver), and what were the specs/current ratings needed?