Testing motor

[JohnnieB]

I didn't disconnect the controller, so there are some turned off MOSFETs in parallel, but they'd have very high resistance on that state and would lower the Ohmic value if they had any significant influence on the reading.

A1 -> A2 = 0.3Ω
F1 -> F2 = 2.0Ω

I used three different digital Ohmmeters, shorted test leads together to get a baseline value and subtracted that value from the armature and field measurements. The readings above are the lowest of the three readings, but the highest reading were only 0.1Ω higher for each, so all three meters were pretty much in agreement. Of course, measuring low Ohmic values with a DMM is iffy, but I no longer have access to a true Milli-Ohmmeter, nor do many golf cart owners.

I have a data log that was recorded via the XCT controller that shows the armature drawing 362.0A with 34.1V applied, which is an impedance of 0.94Ω.

I have three DMMs that say the armature has a DC resistance of about 0.3Ω, which equates to 113.7A with 34.1V applied.

So for some reason the armature is drawing over three times what Ohm's law says it can for the voltage applied.

The DC Ohms could be wrong, the XCT data log could be wrong or there could be other factors involved.

I've sent an email to D&D, hopefully they'll shed some light on the quandary.

[nutsehc]

Have a friends 2003 36 Volt ez go txt PDS that just quit:

Solenoid clicks, reverse buzzer works.
On board diagnostic gives single beep / all terrain chip
Testing motor shows:
A1-A2 =3.19
F1-F2=1.3
F1-A1 =78K
F1-Motorcase (actually bolt holding motor into differential)=starts @ 4 then rises till O.L

Tried sepex motor test shown in Johnny B's post:
A1-F1 jumpered
A2-F2 jumpered
Batt+to A2
Batt- to A1
12 volt battery
No wheel movement
Motor is toast?

Running through manual in diagnostics (page F11)
Step 10 Voltage between Batt B- & Controller A1
0.4-0.8 less than reference Voltage? /no/ Reading is 4.43 volts?
Step 11 Voltage between Batt B1 & Motor A-1
0.4-0.8 less than reference Voltage? / no/ 4.43 volts as well
Controller is toast?

This an older fellow who is just to get this thing to limp along, so the investment may be more than he can bear...Might just buy it from him and do another build, but really hope to help him out....Any help from the gurus out there?
Darn thing has got me stumped

Thanks very much!

[nutsehc]

Anyone have any insight to this issue?