Controller questions

[SilverBack4Jack]

We decided to investigate my controller area today and found I had a curtis pmc 25864g09 controller under that massive cover. Well I am now curious as to why do they have that big cover over the controller and the solenoid. Wouldnt they want air to circulate around it. At one point the temp on the solenoid was 150*. Is that normal? I have noticed that the cart seems to be slowing down while riding around and just doesnt seem to be as fast as it used to be. The batteries are just over 1 year old so I am wondering what to do next to get some more speed. Thanks in advance guys.

[JohnnieB]

Since a 25864g09 is a Curtis model 1206 controller (250 Amp), you must have a cart with a series wound motor.

The hunk of aluminum the controller is bolted to is called a heatsink and that is where the airflow needs to be.
The environmental cover that also bolts to the heat sink is to protect the controller and solenoid from water being splashed on them.
Aftermarket controllers and solenoids that are hermetically sealed, do not need a separate environmental cover.

I'm not sure, but 150 degrees sounds like the solenoid is running a bit on the hot side, so the contacts might be going bad. (IE: They have resistance and current passing through resistance generates heat)

Only two ways to get more speed with a series cart.
1. Increase battery pack voltage.
2. Increase tire diameter.

If you go to a higher voltage, you have to upgrade the controller and solenoid to match.

If you install taller tires, you gain speed, but lose torque, so you have to upgrade to a controller and solenoid that will allow the motor to draw more amps to regain the lost torque, or learn to live with a cart that slows to a crawl on inclines.

When you upgrade controller and solenoid to handle higher current, you also want to upgrade high current cables (all 13 of them) and F/R switch since total current flows though them also.

[SilverBack4Jack]

So if I were to go with a larger controller or have the motor worked on that wouldnt gain me anything? I was thinking a 400 amp controller and some motor winding would gain me something. The batteries are only a year old and have 4 gauge wires but i reckon I need to replace the solenoid to make sure it doesnt strand me somewhere.

[scottyb]

Think of the controller as a valve, the bigger the valve the more amperage can flow to the motor at any given time. A 250 amp control and a 60amp solenoid was good for golf. If you go with a rewind motor & a larger control to allow the motor to produce more torque, you will have to upgrade the solenoid also. Typically a 200amp HD solenoid will do the job. This would increase performance. You should also have 4g cables & HD F&R switch to handle the amperage delivery.
For more information on controller selection check out the controller packages at http://cartsunlimited.net/Custom_Options.html

[JohnnieB]

Originally Posted by SilverBack4Jack

So if I were to go with a larger controller or have the motor worked on that wouldnt gain me anything? I was thinking a 400 amp controller and some motor winding would gain me something. The batteries are only a year old and have 4 gauge wires but i reckon I need to replace the solenoid to make sure it doesnt strand me somewhere.

I was mistaken to say "Only two ways". You can change the motor and/or change the gears in the differential also. Higher voltage and taller tires are just the more common ways. (Actually taller tires is changing the final drive ratio, as is changing the differential gears)

Just putting in a 400A controller won't get you any more speed. It will get you more torque, but will put more stress on the cables and F/R switch.
Just putting in a high speed motor might not get you much more speed since a stock controller can't feed it enough current to realize its full potential, and the stock cables and F/R switch might limit its performance also.

The trick is that the whole system has to be matched.
Figure out what you want the end result to be and build toward that goal.

If you've already got 4Ga cables throughout and good batteries, you'll probably need a HD F/R and solenoid as well as a 400A (or larger) controller top feed a high speed motor.