Hello, long time lurker, first time poster here. I am having a problem that probably has a simple solution, but that solution is escaping me. I have a thyristor-based voltage controller feeding a full-wave bridge rectifier to provide approx 48VDC. The rectifier is loaded with 4x10000uf caps (rated at 63V) for voltage smoothing, and 8 100W peltier coolers. When I turn up the thyristor to 30-50VDC, everything works BUT the 14ga cord always gets warm/hot and the 20A breaker at the panel always flips after 20+ seconds. This makes no sense to me because I have a DC shunt measuring the current draw of the peltiers at *only* 500-700W, and an AC current measurement using a Kill-a-Watt device of only 7A....
With such a small DC wattage draw, what could be causing such a large (and miscalculated?) AC power draw? The only thing I can think of is reverse voltage breakdown at the rectifier and backfeeding the AC supply, but that shouldn't be happening with only 50VDC coming from the caps.... Hopefully my diagram is of some assistance.
Thanks for the help!
P.S. - In case it helps, here are the actual voltage controller/rectifier/caps:
Caps - https://www.amazon.com/gp/product/B07R1X6DPJ/
Voltage controller - https://www.amazon.com/gp/product/B087JBGHXG/
Rectifier - https://www.amazon.com/gp/product/B07JC3Z79N/
With such a small DC wattage draw, what could be causing such a large (and miscalculated?) AC power draw? The only thing I can think of is reverse voltage breakdown at the rectifier and backfeeding the AC supply, but that shouldn't be happening with only 50VDC coming from the caps.... Hopefully my diagram is of some assistance.
Thanks for the help!
P.S. - In case it helps, here are the actual voltage controller/rectifier/caps:
Caps - https://www.amazon.com/gp/product/B07R1X6DPJ/
Voltage controller - https://www.amazon.com/gp/product/B087JBGHXG/
Rectifier - https://www.amazon.com/gp/product/B07JC3Z79N/
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