Hello all- I just received an email through RadSafe indicating that the sender had found HV capacitors containing Th-232. Now, I've never heard of such a thing, and I can't imagine why it would be of use. However, the knowledge base here is considerably larger than my own, and I'm hoping someone here can solve the mystery.
Text from email: "We recently came across some items labeled as capacitors that have Th-232, on the order of 4-5 uCi (1.5E5-1.85E5 Bq) each in a 2" x 13" cylinder. They were part of 375 kV (electric) breakers. The Th-232 was determined by HpGe spectroscopy. They are not ceramic insulators. There is no manufacturer data on them, just a simple label - Capacitance at rated voltage 208 pF @ rated power, Power factor at 10kV - max 65kV.
Does anybody have an idea of what function they provided, and why there's so much Th-232 in them? I've never heard of Th-232 being in capacitors. The breaker was built in 1980, I don't know if they are original."
HV Capacitors containing Thorium
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JakeJHecla
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Richard Hull
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Re: HV Capacitors containing Thorium
Thoriated tungsten is often placed in large contact pads of breakers and other electrical switch gear, if a lot of current is switched. A simple GM counter should locate the part with the thorium in it. Some times the capacitors are series connected ceramic units if you bust into the cylinders and not foil caps at all. The capacitor bodies or the capacitors might have thorium in them. Cool!
Richard Hull
Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
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Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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John Futter
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Re: HV Capacitors containing Thorium
Jake
These are not capacitors
they are circuit breakers the capacitance rating is just the capacitance when the breaker is open
They use thoriated emitter to establish the arc at a known robust point ready to be blown out by air as the breaker opens
These are not capacitors
they are circuit breakers the capacitance rating is just the capacitance when the breaker is open
They use thoriated emitter to establish the arc at a known robust point ready to be blown out by air as the breaker opens