Low resistance

The coils will have higher "resistance" (reactance) when AC current is applied, if you can find a wall wart with AC output (possibly a dial-up modem wall-wart) with approx' 12V output - hook it up with a dial or indicator bulb in series, a gross difference in brightness between any two identical windings would indicate a problem. You can also make use of your meter on its AC voltage range for a more precise indication.

If you really do need an actual DC resistance measurement, the easiest way is to apply a regulated (and known) current to the winding and then measure the voltage developed, from there its a simple Ohm's law calculation: V/A=R.

This topic comes up frequently on News:rec.motorcycles.tech so the regulars have had plenty of practice giving advice.

You don't need to be registered to vote to measure resistance.

Sorry, couldn't er... resist.

I bet you voted for Obama!

use Ohms law.

pass a known current like 100mA through the coil (eg use a 120 ohm resistor and a 12V supply) and measure the current using your DMM

(view with fixed pitch font - eg cut and paster into notepad)

then divide current by voltage eg 150mV/100mA=1.50 ohms.

For the DC measurement, if you have not a regulated current source, and if your DVM can not measure current, try the following:

- buy a resistor between 1.5ohm to 15ohm, let's say R;

- put it in serial with the coil;

- put some DC voltage across the two resistors;

- measure the voltage around the coil (Vc) and around the resistor (Vr)

- compute coil resistance: Rc = (Vc)/(Vr)*R

Warning: depending the DC voltage and the value of R, you have to correctly select the power of R. Do not put too much DV voltage. For example, if R = 4.7ohm and if you apply 5V, then power =

Olivier