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New Variac for Joule Electra Amps

I have a pair of Joule Electra VZN-160 amps and have been using them happily for the last six years. They use a single outboard variac for voltage regulation. I how have a problem where something inside (the core) is glowing and a burning smell starts to manifest.

I'm able to send it in to their out-of-warranty repair facility for a likely core replacement (likely $500ish or more) though it will take ten weeks before it ships back.

Has anyone got other ideas on how to fix this issue? Is there any after-market variac that would work, or could I just somehow get a new one?

Thanks in advance for any suggestions.
outlier
jea48
2,944 posts
 
Outlier,

Is your Variac one that self-adjusts to keep the voltage constant within a fairly tight tolerance? Possibly made by Monster?
http://www.amazon.com/Monster-Cable-MPPROAVS2000-Channel-Conditioner/dp/B0002ZO5W2

Or is it the type where you set it manually to raise or lower the voltage for the desired loaded output voltage of the unit?

Does you mains voltage fluctuate a lot? Or are you just trying to compensate for a too high or too low of a voltage? If the latter you could use a buck/boost transformer configured as an autotransformer to solve the voltage problem
outlier's avatar
outlier OP
381 posts
 
Hi Jea48,
Thanks for the input. The variac is the latter; manually 'dialed up' to operating voltage of approximately 166 volts. It's not a branded variac; it came with the amps, and am sure is designed for the amps. It's part of how the joule amps work. Even the latest Joule amps have a variac, but they are internal, one per amp, but mine is a single, outboard one. It's not an optional piece of kit - my amps won't function without it.

The reason I need a new (or rebuilt) one is because it's no longer working properly; the core has likely failed, because it's sparking a bit when I initially dial it up, and then glowing, with a slight burning smell when operating.
thaluza's avatar
thaluza
172 posts
 
I have a VZN-80. It is 7 years old. Last year, the variac started to get very hot and there was a burning smell. I did not look to see if there was any glowing. I took the variac to my local tech, and it turned out the problem was a defective fuse holder. He said the one provided by Joule was under-spec'd. He put in a higher value fuse holder, and all has been well since.
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