8mm Forum: question about lamp wattage...

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Posted by Ilias Sifakis (Member # 2417) on June 22, 2011, 02:26 PM:

Ok, maybe its a silly question, maybe i'm just stupid or maybe the new projector I found has electrical problems....

Here's the question, if I use a 100w lamp on a projector that takes 150w lamp, will I burn the 100 w lamp?

I managed to burn instantly 2 nice new xenophot (cry) lamps by trying them on a sankyo 702 sound I found a couple of weeks ago at the local flea market.

If it helps a bit, the projector had a 150 w lamp on it, which seemed old and was seriously overheating, to the point that the inner plastic of the cover above the lamp was slightly melted (!)

Did I just acted like a stupid noob and burnt my lamps or the projector has an electrical problem?

thanks in advance
ilias

Posted by Antonis Galanakis (Member # 1455) on June 22, 2011, 03:04 PM:

Ilia
Usually the 150 Watt lamps are 15 Volt. If you used 100 Watt they were probably 12 Volt. So this is why you burned them (I cry too).
Antonis

Posted by Ilias Sifakis (Member # 2417) on June 23, 2011, 12:24 AM:

thanks Antonis,

it's official then...i'm with stupid [Razz]

hahahahah
I never thought to check the voltage...only checked the wattage and thought that it would be ok..but yeah...voltage is capable of burning things.....pfffff
two new xenophot in the drain cause of my ignorance [Frown]

Posted by Lee Mannering (Member # 728) on June 23, 2011, 04:27 AM:

Ilias. Its worth checking that the metal heat shield is also present inside the lamp house front cover, if not it may well melt the plastic. All my Sankyo machines used to bulge on the top of the plastic cover where the black air vent slots are so this was a normal feature for Sankyo sound machines and a poor design flaw. The 702 does need a 15 volt 150 watt lamp though.
Happy days!

Posted by Ilias Sifakis (Member # 2417) on June 23, 2011, 04:33 AM:

thanks a lot for your reply Lee,
what you're describing is exactly the area where the plastic is a bit melted...the shield is present around the lamp and above.
I'll try finding some photos on th web though to check if all shielding is there...or else i'll post a photo here for confirmation..

For the lamps..I blame my stupidity...
i thought about the wattage difference and I was sure the lamp wouldn't burn from that, but I never considered the voltage..although I knew the damage they could cause...

Anyway, it's ok...knowledge costs these days [Big Grin]

and i've learned a lot about 8mm from my own mistakes and blew ups so far!
Noone is flawless and i'm learning every day something new about the 8mm scene [Big Grin]

thank you all!

Posted by Lee Mannering (Member # 728) on June 23, 2011, 05:10 AM:

Ilias. I bet we have all put the wrong dichroic lamp in a machine at some point my friend and I’ve also had a one or two machines blow up as well, but its all part of the fun. Best explosion I ever had was from a 1940’s sound projector which exploded mid film just behind the audience’s heads. Everyone seemed to jump up a foot in the air when it went bang and I sort of disappeared in a cloud of smoke. It was like a scene from a carry on film and I fell about laughing, luckily not holding anything on the machine at the time. In later years I learned it paid to rewire vintage machines as the old ones had cotton wound wiring inside. We live and learn as they say.

Posted by Ilias Sifakis (Member # 2417) on June 23, 2011, 05:12 AM:

hehe I wish you had a super 8mm camera set to capture that lovely explosion scene [Razz]

I totally agree, we live and learn...and that's a great part of the hobby!
I'm just happy I can at least find cheap projectors at the flea market to experiment with [Wink]

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