Electric Newbie, measuring current?
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Electric Newbie, measuring current?
Please excuse my ignorance but I'm pretty new to electric.
I'm keen on playing around with some prop combination's and would like to know what current each is drawing.
I have a multimeter, can I connect this in serial between my battery and speed controller to measure how man amps I am burning?
I'm keen on playing around with some prop combination's and would like to know what current each is drawing.
I have a multimeter, can I connect this in serial between my battery and speed controller to measure how man amps I am burning?
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RE: Electric Newbie, measuring current?
My multimeter said it could...but I could never get it to work...it always interrupted the current and the system wouldn't run....
I ended up getting a Watts Up meter and I am very glad I did....
I use it quite a bit...
and I have used it with my charger to double check and make sure the charger is pushing the current it says it is.....
I ended up getting a Watts Up meter and I am very glad I did....
I use it quite a bit...
and I have used it with my charger to double check and make sure the charger is pushing the current it says it is.....
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RE: Electric Newbie, measuring current?
The length of the cable between the speed controller and battery is absolute critical. The latest speed controllers list arround 15cm max. Over this length you stand a very good change of the speed controller being damaged beyond repair. Also if you insert a meter with high resistance the same can occur. To check currents, ONLY use a wattmeter such as the Astro or a clip on DC meter that clips over the + lead from the battery. The length of cable from the controller to the motor is not critical. Inserted multimeters is NOT a good idea. Electronics Engineer.
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RE: Electric Newbie, measuring current?
You can use a multimeter, but you need to be careful. Most multimeters can only measure 10 Amps or less, and then for only 10 to 30 seconds at a time before they trip a thermal protection circuit (or burn up).
Another option besides a Whattmeter (which may not be available in S Africa) is measuring the voltage drop across a low-resistance shunt. You would need a piece of wire with exactly .001 Ohms resistance to connect in series between the battery and ESC, then you could use the milliVolt scale on your multimeter to read the voltage drop across it. Each milliVolt would equal one Amp of current draw. Don't quote me on this, but a 12" (305mm) piece of 12 gauge solid copper wire is what I recall people using.
Another option besides a Whattmeter (which may not be available in S Africa) is measuring the voltage drop across a low-resistance shunt. You would need a piece of wire with exactly .001 Ohms resistance to connect in series between the battery and ESC, then you could use the milliVolt scale on your multimeter to read the voltage drop across it. Each milliVolt would equal one Amp of current draw. Don't quote me on this, but a 12" (305mm) piece of 12 gauge solid copper wire is what I recall people using.
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RE: Electric Newbie, measuring current?
The first two things you should buy is a Watt Meter (Astroflite or Medusa) and a temperature gun to measure battery and motor temperatures.