Elmo GS1200 electrical issue

[Steven J. Kirk]

Okay, so I have a GS1200 that trips the household circuit breaker after only 30 seconds or so when switched on. I'm in the UK so it is 240volts. The machine is the correct voltage and the transformer is set to 240v. I'm imagining an Earthing problem but does anyone have any ideas where to start. Is it something simple that comes up with these machines?

[Steve Klare]

Hi Steve,

It's interesting that you trip the panel breaker yet the much lower value fuse inside the GS seems to be weathering the storm.

Here a normal household breaker is sized to provide something up to about 1800 Watts, and yet even the Xenon GS is fused to allow only 450W. Somehow you have an excess of at least 1350W flowing in and still not blowing that projector fuse.

That's a lot of power and most likely a lot of heat. What's a hair dryer or a waffle iron, like 1500W?

What I would do in your position is operate the thing for that 30 seconds and whether or not the breaker blows, stop and (please!) unplug.

Bearing in mind that things like capacitors store energy for a while after unplugging, run the back of your hand over non-metallic surfaces and feel where the heat is winding up (-not the lamp, that's a given!)

Based on the internal fuse seeming to stay intact, I'm a little suspicious of your line cord. If there was some developing internal short, it could conduct that excess current and leave the machine's fuse completely unharmed. The fuse is supposed to be the first thing inside the machine after the power inlet, so my wild guess is the power cord, the inlet it plugs into, or the wiring from there over to the fuse.

-Ohhhhh...you wouldn't happen to have a waffle iron plugged into the same line, would you? I love waffles, but they could be a problem here! (-just saying!)

[Steven J. Kirk]

Thanks for your input, Steve. That's right the fuses inside the machine are okay. The machine was a recent purchase as a 'spares' machine but I thought I would try to get it running. I suspect damp damage because the lens shows little spirals of 'fungus'.

[Ken Finch]

As Steve suggests, it could simply be that you have other appliances plugged in and on in that particular house circuit. In the U.K. most appliances have fused plugs. Of 13amps or less depending on the appliance. If this blows it also often trips the circuit breaker of that particular house circuit as well. You could check the projector lead to see if that is the problem as Steve also suggested.

[Steve Klare]

Hi Steve,

What you could try is kind of a layered approach to figuring out where the problems start.

1) Plug in the machine with sound. lamp and transport all turned off.
2) Wait at least 30 seconds.
3) Turn on the sound.
4) Wait at least 30 seconds.
5) Start up the film transport.
6) Wait at least 30 seconds.
7) Turn on the lamp.
8) Wait...you knowww...

When does the breaker pop?

If if pops before step #8, that's a smoking gun.

[Brian Fretwell]

As the internal and plug fuses stay OK, as you say, it looks like a current on the earth wire that is tripping the RCD. Perhaps a supression capacitor is leaking to earth the current building up in the 30 seconds it runs.

[Graham Ritchie]

Sounds like a dead short to me, of live mains voltage to neutral or earth, very dangerous in my book so be careful