I have this old but intact HV transformer from a microwave oven that
(wonder of wonders) doesn't require knocking out the shunt to use.
Predictably, it has one end of the HV winding tied to the frame of the
transformer. Hoerver, the insulation between the HV windings and the
laminations doesn't look good to withstand 2.5 KV.
Am I better off to:
1) Lift the winding to ground and attach it to my rectifier bridge, while
grounding the transformer frame, and take my chances on the insulation.
2) "Float" the transformer frame by placing it on suitable insulated
standoffs, and attach the bridge to the frame and to the other end of the
HV winding? I would provide a reasonable guard cage around the transformer.
I favor #1, because if the insulation goes, I blow the (free) transformer,
a fue or two, and maybe trip a breaker as the smoke leaks out.
#2 seems unsafe, because if a fault condition developed, the HV could be
present on the primary, and the potential against line neutral or line
ground could be lethal and undetectable.
Comments?
If you don't hear back from me tomorrow, it's because I picked the wrong
one! ;)
Jim N6OTQ
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