EZGO 36v DCS electric only 25v under load on A1 to motor?

[JohnnieB]

Originally Posted by Great white north

Always put negative lead of DVM on negative post of pack voltage , when doing readings , move positive lead of DVM to different test points

Not "Always", just most of the time.
There are times that the voltage between two points is more meaningful or easier to interpret than the voltage from Battery negative to a point.

To be 100% correct, the statement should read "Unless otherwise specified, always put negative..."

[JohnnieB]

Originally Posted by Steveleavitt7777

OK guys here is the volts reading on the motor. I have A1 S1 A2 S2 markings on the posts.
All readings are in run mode, key on

A1 nor A2 have zero reading. pack negative to voltmeter red reads 38 volts on both contacts. When I push the peddle A2 goes down to 35.5. A1 starts at 38 down to 36 when solenoid engages and down to 26 with peddle all the way down.

testing a1 to s1 as the peddle is being pushed goes from 38 down to 26
A2 to S2 as you push the peddle goes from 38 to 32

when they are supposed to be at zero where do you connect the negative lead on the volt meter?

Does this tell you anything?

Before disconnecting or connection any electrical wiring, always place Run/Tow switch in Tow. Otherwise the controller may be damaged.

The voltage reading you are getting prior to the solenoid clicking (contacts closing) are due the the resistor across the solenoids big terminals (contacts).
Either remove the resistor or disregard the meaningless voltages observed before the solenoid clicks.

The A2 terminal on the motor connects directly to the solenoid output and B+ from the battery pack ties directly to the solenoid input, so when the DVM's negative test lead is attached to B- at battery pack, you will measure FULL battery pack voltage during the entire time the solenoid contacts are close. If a significant number of Amps are being drawn from the battery pack, this voltage will decrease a few volts due to battery pack loading.

The voltage on the A1 terminal will vary proportionally to how far the controller's control element is turned on. Basically, the battery pack voltage is divided between the motor's armature and the controller's control element.
Measuring from B- at the battery pack to A1, you are measuring across the control element and when the solenoid first clicks, the throttle is not telling the control element to send Amps through the motor, so the entire battery pack voltage is dropped across control element.
Therefore, when the solenoid first clicks, you should measure Full battery pack voltage at A1.

As the pedal is press further, the throttle (ITS) tells the controller to turn the control element on and the further the pedal is pressed, the further the control element is turned on and less voltage is being dropped across it, so more voltage is applied to motor armature.
Therefore, as the pedal is pressed to floor, the voltage at A1 will decrease towards Zero. When and if the throttle is telling the controller to turn the control element fully on, and the controller is doing what it is being told to do, the voltage at A1 will be Zero plus about 0.3V for every 100A of current flowing.

In a nutshell, with key ON, F/R in F and DVM negative test lead on B- at battery pack, A1 should read FULL battery pack voltage when solenoid first clicks and decrease to Zero or near Zero as pedal is pushed to floor.

Checking the ITS:
Key ON, F/R in F and DVM negative test lead on B- at battery pack.
Pin-2 (Black wire) should read 14V-15V.
Pin-2 (White wire) should read 0.4V-0.6V when solenoid first clicks and 1.5V-1.7V when pedal is fully depressed.

Checking Field excitation voltage:
DVM Negative test lead on F1 and Positive test lead on F2
Key ON, F/R in F and Pedal fully depressed
Should read approximately 8V. (Polarity of voltage depends on whether F/R is in F or is in R)

Let us know what you find. There may be more than on problem.

[scottyb]

Very odd since the control does the directional switching and the ITS signal is identical in F&R? Check those cables to the motor as shown. And check the battery pack under load.

[Great white north]

Sorry Jhonnie , my bad , you are 100% correct
Regarding where to put neg.lead of DVM

[austinwells114]

I am having an issue with a cart that will not go over about 5MPH. Suspecting it was the high speed circuit of the controller and everything seeming to test okay I replace the controller with the same issue now. Only thing strange I can find is the ITS black wire has 14v and the white wire has 14v with the pedal not depressed or depressed. The black wire has 0.75 not depressed and 2.9 fully depressed. It seems backwards to me? Working on an ezgo txt pds I think? The rocker is next to the key switch. Also A1 to B- is only at 18v with pedal fully depressed.

[cdressel]

You are replying to posts that are ten years old. It's much better to post your question in a new post.
Chuck