Simple Question

[Solenoids]

Forgive me for wasting anyone's time, but my experience is limited and I have made some expensive mistakes with power cables and have found it is best if I run it by you guys before doing anything with the power stuff.

I believe that my main contactor (MZJ-400 amp) may be robbing power from my system and I would like to check it out before ordering a replacement.

It is very difficult to get to it out so I'd like to run a test on it before I do so.

The question is: May I just bypass the MZJ-400 by connecting the MZJ's power input cable to its power output cable (thereby bypassing the MZJ-400) and then run it a couple of miles to see if the performance of the cart increases? (Of, course without damaging anything.)

The cart seems to be consuming more power and going slower both in street mode and golf course mode.

So, my guess is that I am losing a lot of electricity.

Back ground: 2003 G22E, EMP bimodal motor, just washed and inspected, 850 amp controller, 1/0 gauge power wiring, new Trojan 890 batteries, 2 SW202 contactors, one for F/R and one for mode control both recently dissembled and cleaned as well. All power cables are in fine shape and solidly connected.

Thanks, Jerry

[whizzo]

Jerry mate, if you do not have a multimeter, now is the time to go and buy one.

With yor multimeter and a couple of made up test leads, you can test many elements in your circuit for voltage drop and under varying load.

In the case of tresting your solenoid, you would simply connect one lead either side of the solenoid contacts and observe the voltage.

Sitting idle you should have full pack voltage across the solenoid, at other times it will vary...it should be fairly low....

what the voltage should be across a helthy solenoid, I have not the experience to say.....a couple of hundred amps thru a set of contacts and you may be surprised how much voltage is there.

If you have the specs on your solenoid, using ohms law and the stated contact resistance you should be able to calculate a likely voltage drop.

cheers

[Solenoids]

Per your suggestion, I turned the key switch on and used the meter to measure the difference in the voltage on both sides of the master solenoid. Please make sure I did it right: I probed the B- and the B+ input to the master solenoid. The reading was 50.5 V. Then I probed the B- to the B+ on the solenoids output side and the reading was 46.4 V.

So the difference between the input and output sides of the master solenoid was 4.1 V or about 10% drop. And, the solenoid is bad.

Sounds like too much drop to me, but what do you guys think?

Thanks, Jerry