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BrianG · 09.30.2006, 02:41 PM

Low resistances are better measured with a conductance meter. Conductance is simply 1/resistance, but is measured a different way for really low resistances. You're going to have a hard time measuring coild resistance even with a decent meter. Most ohm-meters can display only as low as 1/10 of an ohm. If that is the lowest value, the resolution won't be great.

Don't forget to account for meter lead resistance. To get a baseline "0", short the leads together and read the resistance value. Subtract this from whatever you measure on the coils.

Whatever you do measure will be VERY VERY low because you are just measuring DC resistance since it's just a length of wire. Most of the impedance will come from the inductive reactance properties of the coil. To take this into account is a little complex. You'd have to take an inductance reading, know the frequency the ESC operates at, calculate the inductive reactance, then combine this value with the DC resistance. You can't just add these values since inductive reactance is 90 degrees out of phase with pure resistance, so the result would be a vector.

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BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	09.30.2006, 02:41 PM Low resistances are better measured with a conductance meter. Conductance is simply 1/resistance, but is measured a different way for really low resistances. You're going to have a hard time measuring coild resistance even with a decent meter. Most ohm-meters can display only as low as 1/10 of an ohm. If that is the lowest value, the resolution won't be great. Don't forget to account for meter lead resistance. To get a baseline "0", short the leads together and read the resistance value. Subtract this from whatever you measure on the coils. Whatever you do measure will be VERY VERY low because you are just measuring DC resistance since it's just a length of wire. Most of the impedance will come from the inductive reactance properties of the coil. To take this into account is a little complex. You'd have to take an inductance reading, know the frequency the ESC operates at, calculate the inductive reactance, then combine this value with the DC resistance. You can't just add these values since inductive reactance is 90 degrees out of phase with pure resistance, so the result would be a vector.