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BrianG · 08.02.2009, 02:09 PM

Sorry, yeah, it's the 150A version.

Not sure about what effects ripple and/or voltage drop would have. It is essentially just a voltmeter with a seperate hall-effect sensor for current. Voltmeters typically have high input impedance, so the ripple would just look like changing DC. And the hall-effect sensor is an isolated circuit. The current measuring part is electrically seperate from the part that measures it, and looks like a straight piece of wire as far as resistance goes. So, I wouldn't think ripple is a big deal at all. I just think the current exceeded the sensor's spec.

Allegro Microsystems (the company that makes the actual hall-effect sensor IC) also makes a 200A version. I emailed ET and asked if this IC could be used in place. But, I'm afraid the answer will be "no". Even though the IC is pin-compatible, I assume firmware changes would be necessary for the rest of the circuit to recognize the higher current. These hall-effect sensors are pretty simple really: They output a linear voltage in proportion to the current. If the circuit expects to see 0v @ 0A and 5v @ 150A, the new sensor will ouput that 5v at 200A instead making the readings all wrong. I'd have to re-interpret the results for every test I take.

	(#5)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	08.02.2009, 02:09 PM Sorry, yeah, it's the 150A version. Not sure about what effects ripple and/or voltage drop would have. It is essentially just a voltmeter with a seperate hall-effect sensor for current. Voltmeters typically have high input impedance, so the ripple would just look like changing DC. And the hall-effect sensor is an isolated circuit. The current measuring part is electrically seperate from the part that measures it, and looks like a straight piece of wire as far as resistance goes. So, I wouldn't think ripple is a big deal at all. I just think the current exceeded the sensor's spec. Allegro Microsystems (the company that makes the actual hall-effect sensor IC) also makes a 200A version. I emailed ET and asked if this IC could be used in place. But, I'm afraid the answer will be "no". Even though the IC is pin-compatible, I assume firmware changes would be necessary for the rest of the circuit to recognize the higher current. These hall-effect sensors are pretty simple really: They output a linear voltage in proportion to the current. If the circuit expects to see 0v @ 0A and 5v @ 150A, the new sensor will ouput that 5v at 200A instead making the readings all wrong. I'd have to re-interpret the results for every test I take.