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Re: [Amps] SB220 step start blows fuses

To: amps <amps@contesting.com>
Subject: Re: [Amps] SB220 step start blows fuses
From: Warren Volz <warren@warrenvolz.com>
Date: Thu, 6 Jul 2017 00:07:50 -0600
List-post: <mailto:amps@contesting.com>
Thank you for the flood of good suggestions. I'm getting closer.

Without tubes and with the HV transformer unplugged, the fan and meter lights 
work. In addition, the step-start fuses don’t blow!

That leads me to suspect the tubes + HV supply. I checked the windings on the 
HV transformer to look for shorts:

BLK-YEL = .7 Ohm
BLK-BLKYEL = .6 Ohm
BLKYEL-YEL = 0 Ohm
BLKGRN - BLU = .8 Ohm
BLKGRN - BLKRED = .6 Ohm
BLU - BLKRED = 0 Ohm

Do any of those look off?

Also, would these steps (or something similar) make sense?

1) Re-enable HV supply, power on, if fuses are ok power off and go to step 2
2) Once HV dissipates, add tube 1, if fuses are ok, power off and go to step 3
3) Assume tube 2 is shorted, else tube 1 is bad

-Warren
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