Lightmaker 6,000/12,000watt ballast

[Bob Hart]

Is anyone here using this ballast for 12K HMI in the UK or Australia? In the US they draw power from across phases for 240VAC so the wiring for this light there in effect does not have a neutral pole. Their 220V 100amp Bates stage plug has three pins, two "hot" and an earth pin. The ballast will work on Australian 240VAC 50Hz power.

In Australia, 240V is single phase. This means an active, neutral and earth. I will be having a qualified electrician hook this thing up via a Mareschal multipin plug for a test on a generator. Any info on which of the two "hot" pins in the military input connector on the ballast should be the neutral would be appreciated. The "A" pin is the earth, that much is stated on the appliance.

There are red and black internal connections and the earth connection is the traditional green/yellow, so my guess is the black would be preferred as the neutral. Both wires go individually directly to heavy duty bolted fuses, thence as far as I can determine to a DC rectifier. The info is required to make life easier for the electrician. I won't be touching it other than to blow dust and spiders out.

Any info will be appreciated.

[Bob Grant]

Red wire is traditionally active and black neutral as you've guessed.
Transposing them should make no difference to the functioning of the device. On the other hand it could make a difference to the safety of the device as our neutral is connected to earth. If the device is directly rectifying the 240VAC mains and there is no isolation between the DC output of the rectifier and the lamp then both wires to the lamp could be at a considerable voltage relative to earth. Fitting a RCD internally to the device would seem a wise precaution that would not cost much. The other alternative would be an isolation transformer but that will be expensive and quite heavy.

[Bob Hart]

Bob.


Thanks for that info.

I hope to hook it up at last to a generator soon as in point it away, shut eyes and shove fingers in ears and pray.

I went through all the mounts and connections inside and found a dodgy one, a loose bulb grip which must have caused some problems as it was blacked from resistive contact, not obvious but hidden. May be why the light was traded in.

Since my first post I got some info from a guru on the Lightmaker at an outfit named Galaxy in the US. He confirmed what I had assumed by the internal wiring colours.

Do you know what the gap between electrodes of a serviceable double-ended globe should be? The one I have looks a bit wide.

The Hobbs meter on the back has 11,000+ hours up on it, so the light seems to have earned its keep.

[Bob Grant]

Originally Posted by Bob Hart

Bob.


Thanks for that info.

Do you know what the gap between electrodes of a serviceable double-ended globe should be? The one I have looks a bit wide.

The Hobbs meter on the back has 11,000+ hours up on it, so the light seems to have earned its keep.

I'd expect a reasonable gap in a lamp of that power. I don't think the gap widens with use, the gas wears out. The CT also drops with use so it's pretty easy to judge when the lamp is on its last legs.
At 11,000 hours the lamp will have been replaced many times anyway.

Let us know when you're turning it on, with a bit of luck we'll be able to see the glow in the western sky :)