1999 txt series cart

[scottyb]

We need the model # from the control in your cart with the LED light on it.

[busman9]

Controller is NPX 4834EZ
CONTROLLER.jpg

CONTROLLER (2).jpg

[busman9]

Run more test tonight, clipped the meter to A2 post on the motor and when the cart stalls on an incline the voltage dropped to 29.2V and the light was still green on the controller. I did the same test on another cart that did not stall on the incline and the voltage on A2 never dropped below 32.4. Controller bad? The bad cart has Scotty's heavy duty FR cams and none of the wires or connection are hot. Help!! Thanks

[JohnnieB]

Originally Posted by busman9

Run more test tonight, clipped the meter to A2 post on the motor and when the cart stalls on an incline the voltage dropped to 29.2V and the light was still green on the controller. I did the same test on another cart that did not stall on the incline and the voltage on A2 never dropped below 32.4. Controller bad? The bad cart has Scotty's heavy duty FR cams and none of the wires or connection are hot. Help!! Thanks

A 300A controller is a bit undersized for 25" tires and with the LED staying green with the pedal on the floor, it is saying it is sending the motor the max amps it can pass to it.

The LED turns yellow (orange) when the controller is seeing 100% throttle and is not in current limit, so it is either not seeing 100% throttle or it is passing max amps it is rated for. Look at the LED while flat out on level ground to see if it turns yellow. If it doesn't check the Throttle input signal.

Measure the voltage between the black and white wires with the plug plugged into the controller. Should be 10V with pedal up and 6V with pedal down.

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The pack voltage is dropping to 29.2V, so a lot of current is being drawn, or the battery is weak. Might be a battery failing under load. Check the individual battery voltages under load. The should all drop about the same amount.

Also, batteries have less oomph in colder weather. Trojan says their batteries only have 1/2 the capacity at 0°F that they have at 80°F, which works out to a 6.25% reduction for every 10°F below 80°F.

[busman9]

Johnnie,Run through your test and cart passed all the test. I found another stock controller,Curtis 250 A and installed it and the cart would would climd up the ramp on the trailer. I guess I will be calling ScottyB. Thanks

[JohnnieB]

Originally Posted by busman9

Johnnie,Run through your test and cart passed all the test. I found another stock controller,Curtis 250 A and installed it and the cart would would climd up the ramp on the trailer. I guess I will be calling ScottyB. Thanks

I guess the NPX300 got tired of turning the 25" tires.

[scottyb]

We find about 25% to be the maximum allowable increase in tire size. Mathematically this equates to 22.5". 23" tires are acceptable. Above that the gear ratio increase and torque loss becomes unbearable and the poor electric motors just really cannot deal with these larger tires. One way to run them is to use a reduced rear end gear ratio like 15:1. This is a 25% reduction in gear ratio which brings the big tire user back into very acceptable range, the added weight and loss of fulcrum being the only added tax on the motor.