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Join Date: Apr 2006
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Re: Solar power ~ no more running the engine
"I wanted only 30 amperes to be displayed so I installed a divider across the shunt's output terminals"
foggy, I'm not quite waht you've done but can tell you this is NOT THE WAY TO DO IT.
The way meters and shunts are set up, it doesn't matter what range you want to read. All that matters is that the mv-per-display has been matched between them, and that you don't exceed the maximum amperage that the shunt can carry. Whether you want to read 10 amps, 25 amps, or 50 amps...if you have a meter and 50a shunt, they are set up the same way regardless.
I would strongly suggest that what you've done now is simply to distort all the readings. And, perhaps, that's related to the shunt overheating as well.
Some of the bargain stuff from China, which is SO attractively priced, almost scares me. The shunts are visibly different from the pricey domestic ones, and the all-in-one digital meter displays seem to vary quite widely in quality. (I've got two that never agree, even though they are supposedly calibrated and way exceed their display accuracy.)
50A shunt, 50A meter, put it back to the original configuration and it will read 30A scales just fine. Really.