8mm Forum: SSL Lamp blowing and voltage problem

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Posted by Adrian Winchester (Member # 248) on December 16, 2005, 12:01 PM:

I have a infuriating SSL-2 that I got from France (to the UK), and it seems determined to drive me crazy! The latest reason is as follows:
It was basically a brand new projector that had been stored somewhere for 15 years or more. Therefore, I was surprised when the original lamp blew after about 5 hours. However, the replacement (only used on the low setting) then blew after about one hour. It seemed that the metal parts on the lamp holder might not be conducting well, so I've thoroughly scraped the areas that touch the pins with sharp objects, to ensure that there is good contact. I also rubbed the pins of the next lamp I put in with emery paper. Unfortunately, the next lamp has blown after less than an hour, still on the low setting. I don't think the problem is something to do with the electricity supply in my house, as this isn't happening with the other projectors I use.
The only possible problem I can think of is that the projector is set to 220v, not the customary 240v in the UK, but I didn't think this was significant and would put a strain on the lamps, particularly at the low setting. I believe it may be possible to re-set it to 240v, but it's not at all clear to me from the sticker on the transformer - or the details in the service manual - what exactly should be done to achieve this.

I'd be extremely grateful if anyone could advise on:
a) Whether the 220v setting could be causing the lamps to blow (and if not, what the cause might be).
b) Whether an adjustment to 240v is desirable and feasible.

Thanks,
Adrian

Posted by Kevin Faulkner (Member # 6) on December 16, 2005, 04:04 PM:

Adrian, The answer to both 1 & 2 is yes. As far as I know you can change that over to the 240V setting by moving a tapping on the mains transformer.

Kev.

Posted by John Whittle (Member # 22) on December 16, 2005, 05:40 PM:

Kevin is right, the transformer on the international version can be tapped for the 240 or 220 voltage. The lamp is fed from the primary winding (it's an autotransformer not a real transformer for the lamp circuit) and thus if it's tapped for 220 and you're feeding it 240, then the lamps are geeting a much higher voltage. You might want to read it with a multi-meter, but I'd suspect that you're putting 28 to 30 volts on the lamp.

John

Posted by Adrian Winchester (Member # 248) on December 16, 2005, 06:32 PM:

Kev & John - thanks for your comments on this. I'll see if my brother (who has significant electrical knowledge) can make sense of the connections around the transformer.

It's interesting to note that the original Eiki lamp survived the overload for far longer than the Philips and GE lamps I tried afterwards.

Posted by David Park (Member # 123) on December 28, 2005, 03:46 AM:

Adrian did you get problem sorted?

Posted by Adrian Winchester (Member # 248) on December 31, 2005, 05:46 PM:

David -
I hope so. The projector is now set to 240v, but I've hardly had a chance to use it since then, so I'd better not tempt fate by saying all is fine yet! Hopefully I'll manage a longer test soon. Interestingly, the transformer was producing a slight hum before the adjustment, but it's virtually inaudible now.

Posted by Kevin Faulkner (Member # 6) on January 10, 2006, 07:46 AM:

Sounds like the transformer was under a slight strain set at 220V. Hopefully you should now be ok.

Kev.

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