96 TXT DCS with Alltrax, no go. 5 Red in REVERSE (shudder backwards in FWD)

[yourflorida]

Everything was working fine, Wifey went to ride and fails to go.

Key on. Direction switch to FWD. Strong solenoid click, pack at 37.5v

Press accel, shudders BACKWARDS, moves very little.
Controller, solid green.

Off. Wait.
Switch key on.
Switch Direction to REV, solenoid click, 5 RED Flash on controller.
No go.
B+ cable hot?
Throttle does nothing - RED led x5

Off.

I have check many things, but I am a little weak on the motor tests, and I am worried about the B+ heating up. I tried to meter the S1 S2, off of controller, they appear shorted, but I know I am only looking for a tiny Ohm.

Any help would be great, I have lurked at this site forever and respect you guys.

Thanks.


----------------------
My stable:
'56 Westinghouse (like the washing machine)
'71 Cushman 3-wheel (electric)
'76 Cushman 4-wheel (my runner)
'86 Cushman 3-wheel (gas)
'?? Cushman 3-wheel (gas, parts)
'96 EZgo (Wifey's runner)
'92 EZgo
'86 EZgo
'?? Club Car

[JohnnieB]

An Alltrax DCX controller with early versions of software can erroneously flash an Open Field (5-Red blinks) error. See Note: on attached excerpt from Alltrax manual.

The field windings in a DCS motor ought to measure in the 3Ω to 10Ω range.
If you are getting a short between the F1 and F2 cables, check for worn through insulation were 10 Ga cables are routed around frame. (see picture below)

If the controller's output to the field windings was shorted, it may have taken out the field excitation part of the controller.

[scottyb]

That is exactly where I was gonna go
But the shudder now that is peculiar. A shudder usually indicates a bad battery or a bad connection. (Low power supply) Low voltage would cause high amp draw which could account for B+ cable temp rising.

[JohnnieB]

Some speculating.

If the field excitation output from the controller got wiped out, the controller might see it as an open field and give 5-red flashes.

If the armature excitation part of the controller is still intact, it would be feeding a stalled motor, so the armature current would be whatever the controller's amp limit is and that could warm up all the high current cables. The B+ cable getting hotter than the rest means it has more resistance.

With high amps flowing through the armature, some current is going to be induced into the field windings because the controller's output is PWM rather than straight-line DC. That might create enough magnetic flux get the armature to twitch a bit, which might make the cart shudder.

[scottyb]

Curious to see what the outcome is

[yourflorida]

Good reasoned replies.....

Is there a way for me to test the field excitation section of the controller?

I am not thinking the "bad connection/battery", still strong 37+ even when messing with it.

Thanks again and any tips on checking the field circuit would really be great.

[Volt_Ampere]

S1 and S2 in a Series motor are in Series with the A1, A2 (Armature) The field is a very low resistance. Usually a Sepex motor has the field labeled F1, F2. Which motor do you have?

[JohnnieB]

Originally Posted by Volt_Ampere

S1 and S2 in a Series motor are in Series with the A1, A2 (Armature) The field is a very low resistance. Usually a Sepex motor has the field labeled F1, F2. Which motor do you have?

The field winding terminals on the SepEx motors used in DCS carts were labeled S1 & S2, which probably caused mixed marriages between Series and SepEx motors and controllers, so they were labeled F1 & F2 on the SepEx motors used in PDS carts.

The title of the thread states he has a 96 TXT DCS with an Alltrax controller, so his DCS motor is very likely labeled S1 & S2.

[Volt_Ampere]

Switching F1 and F2 should have reversed direction! It has to. The controller does not know what direction the motor is going - it only knows which way it is energizing the field.

[yourflorida]

Status:

Spoke with Alltrax and they said that the controller is toast.... no good....

Seems that the "open field" error should be on both FWD and REV... Therefore the "Field" circuit is bad.

Gonna get a new controller I guess.

I just poked around in my stable of carts to see if any are close to being put in the game, now that I have a battery pack just sitting around, and discovered that one my older units is a Melex and it has similar setup, S1/S2 on the motor and a serious looking controller. Time to hit the Google, I wonder if that machine is worth a little TLC.

Thanks all of you for the insight and info.