Measuring Amperage

It will take a higher current when motor has a load to move.
Max is called "stall" current. Motor and power supply should survive it, for a short period :wink:

Thanks for all the help!

Krupski/JimboZA: I believe we came to the conclusion that it is not a stepper because it only has two wires. Do steppers some times have only 2 wires? I don't really know I'm just going off what majenko said.

Michel: When testing it I will put some load on it.

I looked online and it did not say if my multimeter has a ammeter in it. What do you guys think? If it doesn't what brand do you recommend me buying?

Thanks !

http://www.sears.com/craftsman-digital-multimeter-with-ac-voltage-detector/p-03482146000P?prdNo=1&blockNo=1&blockType=G1

Yep it does... in the pic on that link, the grey switch segment at about 4 o'clock says "10A".

3 holes for the leads is also a giveaway, since current is usually (always?) measured on its own connection.

Edit... the left hand socket is colour coded grey and also says 10A

Thanks! I will test it out later to day.

Do you think it will be accurate?

As you ask, it might be interesting to you that for current measurement the DMM has to be in series with the circuit.
So you have to put it between the +12V supply and one of the motor pins. The other motor pin then goes to the supply GND (or - Pin).

Accurate enough to multiply by 2 for some safety margin regarding which device should control and supply it finally.
You want results like (100mA, 200mA, 500mA, 1A, 2A, more ), both for high load and free running.

Do you think it will be accurate?

No idea... the maker's documentation should give the tolerances. My Fluke's manual says 1.5%, but then Sears isn't Fluke 8)

Thanks!

On the stepper motor thing, yes we concluded that it wasn't one on account of just having two wires. Steppers do have more than two, because the windings kind of drag the motor round inside as the wires energise the various coils.

Ok. Thanks!

More on your meter....

It looks to me as if the lower current readings (ADC: 2000u, 20m and 200m at 2-3 o'clock) are with the middle socket, but you'll need to read the manual or at least read what it says next to the middle socket: that's obscured in the pic.

Like I said, measure the DC resistance of the motor, then you can work out the stall current @ 12V. Measure the resistance several times, rotating the shaft slightly between readings, and take the lowest reading.