Reverse Voltage Question

[big nd fan]

I have a 1988 DS with a 36v system.

Does the reverse use 36V or a lower voltage?

Does the motor have 2 winding, 1 for forward and 1 for reverse or is the polarity reversed?


Thanks
big nd fan

[LJ12530]

The attached drawing may not be identical to what you have, but should be close enough to answer your questions.
The motor speed is controlled by the wiper switch selecting a different tap on the resistor group. When the pedal is fully depressed the wiper switch would cause the minimum resistance tap to be selected and all 36V would be applied to the motor. Depending upon the position of the pedal, anywhere from 0 to 36V ( in fixed steps ) would be applied to the motor. The F/R switch simply changes the direction of the current resulting in the motor turning the other direction.
Answering your specific questions, a variable voltage ( up to 36 V ) is applied to the motor terminals. Reversing the polarity, via the F/R switch causes the motor to turn in the other direction.

[LJ12530]

http://www.buggiesgonewild.com/elect...se-switch.html

This link might help a bit.


Also check the stickies for some diagrams with wire colors.

[LJ12530]

Saw your previous post about the cart going in reverse only. Looks like you don't have a V glide system.

I've read that some 36V systems use 18V in reverse, some 36V. Do you have an 18V tap off the battery pack that goes the the F/R switch?

I do not believe that any of the motors used have two different field windings. All that is happening is that F/R switch is changing a polarity thus reversing a magnetic field.

I have also seen diagrams where a jumper is placed between two contacts on the F/R switch to apply 36V when in reverse. See attachment created by ScottyB in a previous post to a similar problem.

[big nd fan]

I used the handwritten diagram to wire up the switch and it still does not work.

When I put in forward I have half power with the pedal pressed.

When I put in reverse and DO NOT press the gas pedal, it goes in reverse full speed.

I am about to pull my hair out. I have been doing electronics and electricity all my life and I just cant get it figured out.

If the F/R switch swaps polarity then why does the motor have 2 windings? It has 4 taps so I think it is 2 seperate windings.

Thanks for any pre-christmas panic help.
Big ND Fan

[LJ12530]

One is for the armature and one is for the stator (field). I do not know if your motor is series, compound, etc. There are lots of ways to build reversing motors depending upon what type of DC motor you have. Separate winding wrapped the other direction for the field, switch polarity on armature, or field, etc. Since you only have 2 stator terminals you can't have 2 oppositely wrapped field coils.
I'll do a more research, but I know there are folks on this forum that have dealt with this. I'll send you a couple of links and keep researching.
I will say this. I read about one similar problem and the recommendation, and fix, was to replace all 5 solenoids and switches. The troubleshooting tips had the guy swap around the solenoids. One of the end ones is full voltage, one is zero voltage.
I'll get back with you.

[LJ12530]

A note I found on the forum asked how golf carts reverse direction. The answer was that they reverse the field polarity.

What happens if you disconnect all of the wires from the motor, put a voltmeter across the field wires that you just disconnected and then measure the voltages in N,F and R. I believe you will get 18V when the switch is in R no matter the position of the pedal. In F you should get a varying voltage.

It is possible that the A wires will have to be connected to the motor, but I would disconnect them for the first try.