Post by tschaeikaei on Jun 10, 2018 20:49:02 GMT -5
Hey,
i recently had some problems with the splitter of my Marquee. It is mounted on the aluminium sheet on a 3mm PMMA sheet for increased insulation on the green tube's housing.
Why that? Because i have a 120mm fan at the place they normally sit (the dark grey plastic sheet).
Splitter has been mounted like that for several years and i never had problems. I didn't use the projectors very much in summer time the last years, mostly in winter.
The problem is: there are sparks and smell of ozone from the splitter case and the HV-lead couplings to the chassis as well as audible crackling of variable frequency.
I suppose the warm weather in the last weeks (going with increased humidity) lowers the isolation resistance of the air between splitter case and sheet metal.
Done so far: adding electrical tape and tar soaked insulation hose over the last 2 inches of HV cable as well as the PMMA sheet between splitter and metal.
Results: not so much. crackling got less, but it is still not gone.
Strange to me: the casing of the splitter is electrically leaky. I can hold a screwdriver against the plastic case and pull sparks (about 3 to 5mm) to the sheet metal.
Anyone experienced something like this? Any solutions?
Another question: The Marquee splitters are known to have 3 3.3kOhm resistors inside, each from the input to the individual tube connectors.
I measured these resistors on all 4 splitters i have. They are between 2.8 and 4 kOhms, only 2 resistors were at 3k3 +-.1k.
is this normal? Would it effect anything in the picture if they're out of spec? I do not think so, because if you assume the tubes to be resistive loads, they would have 34,9Mohm
at 1mA. So another 3.3kOhms would not effect the system very much.
Regards, Julian
i recently had some problems with the splitter of my Marquee. It is mounted on the aluminium sheet on a 3mm PMMA sheet for increased insulation on the green tube's housing.
Why that? Because i have a 120mm fan at the place they normally sit (the dark grey plastic sheet).
Splitter has been mounted like that for several years and i never had problems. I didn't use the projectors very much in summer time the last years, mostly in winter.
The problem is: there are sparks and smell of ozone from the splitter case and the HV-lead couplings to the chassis as well as audible crackling of variable frequency.
I suppose the warm weather in the last weeks (going with increased humidity) lowers the isolation resistance of the air between splitter case and sheet metal.
Done so far: adding electrical tape and tar soaked insulation hose over the last 2 inches of HV cable as well as the PMMA sheet between splitter and metal.
Results: not so much. crackling got less, but it is still not gone.
Strange to me: the casing of the splitter is electrically leaky. I can hold a screwdriver against the plastic case and pull sparks (about 3 to 5mm) to the sheet metal.
Anyone experienced something like this? Any solutions?
Another question: The Marquee splitters are known to have 3 3.3kOhm resistors inside, each from the input to the individual tube connectors.
I measured these resistors on all 4 splitters i have. They are between 2.8 and 4 kOhms, only 2 resistors were at 3k3 +-.1k.
is this normal? Would it effect anything in the picture if they're out of spec? I do not think so, because if you assume the tubes to be resistive loads, they would have 34,9Mohm
at 1mA. So another 3.3kOhms would not effect the system very much.
Regards, Julian
