Glassman WG-40P7.5M85

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Isaac Newton Observatory
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Glassman WG-40P7.5M85

Post by Isaac Newton Observatory » Wed May 12, 2010 9:20 pm

ello everyone.
Finally after so long it's high voltage supply. After giving a clean house or disassembled scomprendo voltage multiplier which is single stage. After I've reversed the polarity of the diodes with tin solder. I returned something to clean with alcohol and then I reinstalled everything. I left the factory with jumper back I connected everything and I tried to switch the supply.
Unit turns on without smoke! Very good! First doubts ???!!!
Turn the switch current and the LED lights that marks the current to 7.5 mA. Turning the voltage selector LED remains off and the needle voltage frozen.
Melting is present in the plasma. Slowly the empty and slightly deeper in sight of the voltage that the LED flashes at times. I try to use the voltage selector but nothing changes.
The plasma at a certain point expire high vacuum. trailer finally feels voltage raises the voltage of the voltmeter. But no plasma! Help me what should I do? Jumpers must remain as factory setting?
These are the connections I made
I connected the hot output high voltage
the body of the reactor external ground
Any advice, criticism is well accepted
Regards Fernando
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Wilfried Heil
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Re: Glassman WG-40P7.5M85

Post by Wilfried Heil » Wed May 12, 2010 10:35 pm

Looks like you've got a short circuit somewhere in the multiplier, so that you are getting current, but no voltage. Maybe a shorted HV diode. Did you test the unit before you made your changes?

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Doug Coulter
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Re: Glassman WG-40P7.5M85

Post by Doug Coulter » Thu May 13, 2010 1:24 am

Yes, or maybe now have a shorted diode, they tend to be kind of heat sensitive, and Glassman really blobs up the solder on them. The one I had you couldn't reverse that way anyway, as there was no facility for the regulation circuit to take the other polarity from the voltage sensor off the CW stack, so it would only run wide open, which fried things. I kept the multiplier and stripped the rest for parts to use in other supplies. Some nice drivers and transformers in the one I had - it had 4 transformers in push pull parallel.

I hear some Glassmans can be polarity switched just that easily -- but not the one I happened to get --
Still got a good deal for the 125kv stack in it which works great off my own drivers.
Why guess when you can know? Measure!

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Re: Glassman WG-40P7.5M85

Post by myID » Thu May 13, 2010 12:15 pm


somewhere I have seen something in this forum about reversing a HV supply- I think ist was a Glassman. With that one you did not only have to reverse the diodes but also had to change something in the feedback circuit...
I have no time to go deeper into this but searching the forum (reversing / glassman / multiplier or something like that) might help!
I hope it is not fried already- good luck....


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