Issues after controller upgrade

[scottyb]

Rut Row

[Sir Nuke]

[Shaunb914]

Ok, i finally found some time to do a little troubleshooting. I attached a picture of the solenoid wiring. When the throttle is pressed the solenoid clicks immediately and the lights on the controller blink 4 times to indicate it is an EZGO ITS throttle. This morning after it was sitting overnight i floored the throttle while on jack stands. The controller gave a 2 green and 6 red LED flash alarm code. According to the manual this indicates low throttle under range. I keep holding the throttle down and about 5 or 10 seconds later the tires start spinning, albeit kind of slowly. After holding it down for a while it gets to full speed. Once it gets to full speed it takes off fast and doesn't have the issue again until it has been sitting idle for a while. It's like it has to warm up or something. Seems like I may have a throttle issue, even though it worked fine on the old controller. How would I go about testing the throttle? Could this delay possibly be the controller "learning" the throttle and after it sits for a while it loses what it learned? I'm just taking wild guesses at this point. Also, i tested the voltage between points 1 and 2 on the solenoid (from the drawing scottyb provided) and I get 1.6 volts between the two points until the throttle is pressed, then i get 0 voltage between the two. From ground I get 38.3 volts on point 1 and 36.8 volts on point 2. When the throttle is pressed I get around 37.6 volts on both points 1 and 2. Any suggestions?

[JohnnieB]

When the solenoid is not activated (high current contacts open), the voltage at Point-2 will be lower the what it is at Point-1.
When solenoid is activated (high current contacts closed), both voltages should be the same.

There are several filter capacitors that are kept charged when solenoid's high current contacts are open via the pre-charge resistor that is connected between the solenoid's large terminals. The current flow through that resistor causes the 1.6V voltage drop you are measuring. When the high current contacts close, they short Point-1 to Point-2, so there is no voltage drop.

Have you checked/cleaned the four-wire in-line connector between the cable from the Pedal Box and the wiring harness?
If the connections are corroded or loose, the min and max signal from the ITS sensor may be changing and driving the controller crazy.

According to Alltrax (and the schematic Scotty posted) the Negative (Black) wire from the solenoid's coil (small) terminal, should be connected to the "RLY COIL -" push on connector on the controller rather than the B- terminal.

Also, I've heard that in some SPM installations, a capacitor is needed between the B- terminal and cart frame (Heatsink).

[Shaunb914]

Moving the black wire on the solenoid over to the RLY Coil - terminal on the controller fixed the delay issue. I was following the schematic that was packed in the box with the controller instead of the one in the manual. It showed that wire going to B- on the controller while the manual showed it going to the RLY Coil - terminal. I guess I should've taken a closer look at the one in the manual. I feel a small increase in torque with the new controller...mostly when accelerating at startup, but not quite as much torque going uphill as I hoped for. It seems to go uphill pretty much the same as the stock controller. I have the controller set to Max amps, but when I monitor it while driving up a steep hill it never shows it using more than around 225 amps max. It's rated as a 500 amp controller so I was wondering if this was normal or if I should be seeing more amps being drawn. Could this be an issue where my 4 year old batteries aren't capable of pushing that many amps?

[JohnnieB]

A controller is a valve that limits the number of amps the motor is allowed to draw. A controller with a higher amp rating will allow the motor to draw more amps, but cannot make the motor draw more amps.

How many amps a series motor draws is determined by the motor's RPM and the applied voltage. At some RPM, the maximum amps that specific motor is electrically capable of drawing will be equal to the max amps a stock controller can pass to it. Below that RPM, that motor will be able to draw more amps and generate more torque when fed by a higher amp rated controller, but above that RPM it will draw the same amps as it would with a stock controller, so once the motor RPM exceeds the RPM where its amp draw capability equals the max output of the stock controller, the motor's performance is roughly the same regardless if the controller can pass more amps than the stock controller.


If the Battery Amps and the Motor Amps columns were exactly the same, the PWM output of the controller was at 100% duty cycle , so seeing a max of about 225A on steep hills just meant that 225A was all that the motor was capable of drawing at the RPM it is spinning at with the volts being applied to it at the time.

If the cart was going slower (fewer motor RPM), the amps would have been higher.

[scottyb]

Connecting the solenoid to the control is an option. Not using this safety cut off control connection should not have any effect on the start up of the system. However if it is working better using the RLY connection then the alternative source must be the problem.