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previous: Mark Lavelle I think the 270EX in my Verberator ... -- 10/25/2004 11:15 PM	View Thread

Re: Shorted primary?

10/26/2004 4:01 AM
Enzo	Re: Shorted primary? Disconnect the secondaries altogether so only the primary is connected to the mains. Put an ammeter in place of the fuse, or leave the fuse and connect the meter across the power switch so you can measure draw. The unloaded tranny should not draw more than a tiny bit of current. if it draws moderate or heavy current, then there is trouble inside it. You may have removed the tubes, but with the secondaries connected, you still are applying voltage to filter caps and rectifiers, heater related parts, and so on. Make sure to check the tranny cold for shorts between windings and from each winding to frame. And don't forget to remove any surge suppressor MOVs from the mains input and any death caps. I usually disconnect the primary and connect it to the mains via test leads for this stuff.

10/26/2004 4:01 AM

Enzo

Re: Shorted primary?

Disconnect the secondaries altogether so only the primary is connected to the mains. Put an ammeter in place of the fuse, or leave the fuse and connect the meter across the power switch so you can measure draw. The unloaded tranny should not draw more than a tiny bit of current. if it draws moderate or heavy current, then there is trouble inside it.

You may have removed the tubes, but with the secondaries connected, you still are applying voltage to filter caps and rectifiers, heater related parts, and so on.

Make sure to check the tranny cold for shorts between windings and from each winding to frame.

And don't forget to remove any surge suppressor MOVs from the mains input and any death caps. I usually disconnect the primary and connect it to the mains via test leads for this stuff.