Quote:
Originally Posted by lutach
I'm using a BNP Products DPR-II-150. It is rated for 150, but it's reading beyond that all the time. Blaine from BNP also said, "The best way to measure high current is to add a calibrated shunt across the DPR's current sensor." Which I have no idea what it means.
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What exactly is a DPR-II-150? Any links?
A shunt is simply a very low and very precise resistor placed in series between the source and the load. Usually looks like a thick wire. When current flows through it, a small voltage drop is generated, which can be measured with a simple voltmeter. The trouble is selecting the right size shunt value so that you can get a good reading, yet small enough not to suck up too much of your voltage. And then there is the power dissipation factor. I wouldn't want to drop more than 0.1v at 200A. Even at 0.1v and 200A, the shunt would have to be rated for at least 20w.
BTW: Eagletree does make an add-on sensor that measures up to 300A, but isn't explicitly said to be compatible with the micro e-logger. IIRC, it is for the other recorder unit.