Another project

[Bmatlock00]

Originally Posted by JohnnieB

Interesting concept.

The cables between cart and trailer would be pretty long, so you'd have to use heavy cables.
Every three numbers lower in the AWG number halves the resistance per foot.
IE: A 5' 4Ga cable and a 10' 1Ga cable have about the same total resistance.

The bulkhead or inline connector would have to be pretty healthy also. Probably a 200A or 300A rating.

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The problem I see is what are you going to use for a controller?
An AXE4855 only goes up to 48V and an AXE7245 is only a 450A controller.
However, there are SPM72500 and SPM72650 controllers that work from 24V to 72V, at 500A and 650A respectively.
Also, the solenoid coil voltage would be an issue, but the control circuit can be wired to run on just the 48V pack.

Those inline connectors are used on electric forklifts, so I'm guessing they are pretty heavy duty, although I do not know of their rating. I am planning on selling the 4865 and probably going with an spm72500. Also you are correct, I am planning on wiring the activation circuit for 48v and wiring my led voltage meter to the B+ on the controller so it will show 48v or 72v respectively.

[JohnnieB]

I'd wire the DVM to the battery side large terminal on the solenoid (or the other end of that cable). Otherwise the DVM would only be on when the pedal was pushed.

[Bmatlock00]

Originally Posted by JohnnieB

I'd wire the DVM to the battery side large terminal on the solenoid (or the other end of that cable). Otherwise the DVM would only be on when the pedal was pushed.

Thanks JohnnieB, I don't know what I was thinking. I have seen different setups with a reversing contactor, one setup uses a solenoid, one does not. Isn't the reversing contactor a solenoid in itself, so if I wired it to only activate when the pedal is pushed wouldn't that eliminate the need for a main solenoid? Or would that be over working the contactor?

[JohnnieB]

Originally Posted by Bmatlock00

Thanks JohnnieB, I don't know what I was thinking. I have seen different setups with a reversing contactor, one setup uses a solenoid, one does not. Isn't the reversing contactor a solenoid in itself, so if I wired it to only activate when the pedal is pushed wouldn't that eliminate the need for a main solenoid? Or would that be over working the contactor?

Technically, the correct name for an electromechanical switch is a relay and if high current is being switched, a relay is often called a contactor. Also, a solenoid is actually just the electromagnet and the mechanism that moves the switch's contacts. However, in golf cart circles (and other places) when someone says solenoid, they are referring to a contactor.

A reversing contactor is one or more "solenoids", but the contacts tend to be less robust than those in a main solenoid typically used in carts because they are not intended to be switched while the motor is drawing amps.

For your personal safety and liability as well as the safety of those around you, I strongly recommend a "main solenoid" be used to make and break the main battery connection to the controller.

[yurtle]

Originally Posted by eaglesdad1

Your dog is a bit small to be pulling that trailer don't you think ? J/k looks good

That's not even funny. You should trailer your dog, not the other way around.

[Bmatlock00]

Finally scored some 2" tubing today and got the tongue welded on, please don't laugh at my welds too much. It has been a while.... lol

[Jd62]

Nice job matlock,, this thing begining to look like a trailer

[gonesouth]

Around here (Brooksville, FL) dealers will sell resistance carts without batteries for $100 without trying to bargain down.

[Bmatlock00]

I got a chance to couple the cart up and snap a couple pictures today. I am pretty happy with how it sits, although I think i got the tongue a little long. I may shorten it up, but it really isn't hurting anything.

[jhnmflr]

I have been looking for cart to do this project. Looks good!