HELP! Reducing Clicks on HD Solenoid

[Hunter450]

Originally Posted by Sergio

I definitely think that on a Sepex cart by-passing the MCOR switch is much safer than by-passing the Solenoid activation directly.

If You are not using the Reverse Buzzer all You need is a plain ON/OFF switch and You can get the "switched" +48v at the Solenoid small post that comes from the key switch so no wires need to go to the front of the cart.

BLUF: MCOR did not like my bypassing it's micro switch. In lieu of going to the solenoid small post to get key switch power, I chose to cut the blue wire going to the mcor since its key switch power as well. Connected the blue wire to the green wire going to Pin#6 on controller and when I turned the key switch the solenoid engaged, no blinking codes on the controller but nothing when I press the go pedal.

[Sergio]

By "cut" you mean spliced into the Blue wire?

What does the Alltrax Monitor screen show?


Edit:

Putting a jumper on the MCOR 2-pin connector is a common procedure to test the MCOR micro-switch and it definitely does not prevent the cart from moving.

That is basically what you are doing.

Double check any wires you left disconnected.

[Hunter450]

Here is what I did:
1. Disconnected the 2-pin connector and verified blue wire was key switch power.
2. Cut ( not spliced) the blue & green wires on harness side of 2-pin connector and connected the blue and green together while leaving the 2-pin connector unconnected.
3. Turned key switch to on and solenoid engages.
4. Place FNR in F
5. Press Go pedal and hear micro switch in MCOR - no movement.
6. Added jumper from blue/green connection and sent switch power back to MCOR micro switch - no change
7. Reconnected wires back to factory and cart worked as normal, hearing micro switch then solenoid engages and cart moves with GO pedal.
8. Add jumper between blue and green...same as before, solenoid engages with key switch....place in forward....no movement.

[Sergio]

What comes to mind is that You are getting a "Low Throttle Under-range" and HPD is shutting down the cart, You can verify that in the Monitor screen.

The Alltrax throttle auto-cal makes the 0 throttle the value right after the MCOR micro-switch closes.

Your MCOR must have a good amount of resistance (not necessarily pedal travel) between rest and the time the micro-switch "clicks".

You can try clearing the auto-calibration values and let the Controller re-establish the 0 throttle value (with the jumper in place) to see if it fixes the problem as the calibration may just be off.

There is no reason to disconnect the MCOR 2-pin, just an ON/OFF switch between the Blue and Green will work.

[Hunter450]

Made some headway with getting the MCOR wired back up and added a temporary jumper wire with a simple "On-Off" switch between the blue and green wires. When this switch is "On", the cart is in "Hunt" mode. When switch is "Off" the cart is in "Normal" mode.

Test 1 - Normal Mode

With the cart in "Normal" mode I checked with the tool kit and received no errors after a test run with the solenoid engaging with the micro switch and disengaging after 2 seconds with "GO" pedal up.

Test 2 - Hunt Mode

Turned key switch "on"
Turned jumper switch "on"
Place FNR switch to forward and solenoid engages.
Cart moves forward and reverse with no solenoid clicks as long as I don't stall on Neutral too long or turn the key switch off.
Again, no errors indicated while monitoring with tool kit.

Test-3 Going from "Hunt" mode back to "Normal" mode.
1. Come to a stop.
2. Place FNR switch in "N" after 2 seconds, solenoid disengages.
3. Turn off jumper switch.
4. Turn off key switch and cart is basically parked and no error codes.

THIS WHERE CHANGE OCCURS

While pushing the GO pedal and as soon as the micro switch activates, the solenoid engages and the cart lunges. I check the monitor page and the throttle is at 35% when solenoid clicks which explains the sprint start.

I clear the auto-cal under the controller tab in the took kit and the MCOR micro switch closes at 5% throttle and the solenoid engages at 7-8% throttle and takes off normally.

[Sergio]

The issue is with the MCOR resistance between the pedal UP "resting" position when in hunt mode versus the position after the micro-switch closes in normal mode.

One way around the issue is to "latch" the MCOR micro-switch rather than activating it with the key switch.

It will require a 48v relay and a diode (under $10 for both)

I did a quick diagram below.

The idea is that the relay contacts are wired between the Blue and Green wires of the MCOR.

When the "hunt switch" is OFF, everything works as usual.

When the "hunt switch" is ON, the MCOR micro-switch also sends power to the positive side of the relay coil.

Once the Controller activates the Solenoid, it provides the negative side for the relay coil and the relay closes creating a bridge between the Blue and Green wires.

Lifting the foot OFF the pedal does not change anything since the "hunt switch" is still closed and the relay coil positive side is getting power from the Blue wire.

If You place the cart in Neutral for more than two seconds, the Controller deactivates the main Solenoid which also removes the negative from the relay and it opens the bridge between Blue and Green wires.

Next time you press the pedal, as long as the "hunt switch" is ON, the cycle repeats and the relay latches.

This allows for the MCOR throttle signal to always be the same when the micro-switch closes regardless of the "hunt switch" ON/OFF position.

48v Relay:

https://www.mouser.com/ProductDetail...QaAg4pEALw_wcB

Diode:

https://www.mouser.com/ProductDetail...xY3rLmCS1i8%3D

[Hunter450]

Sergio,

As always, thank you for providing solutions to the special needs of us less educated on these carts. This exercise just exceeded my comfort level when it comes to controls. Also, where I use my cart and for it's intended purpose, I want to keep things as simple as possible and if I can, reduce the potential failure points.

I'm going to keep the temporary "Hunt" switch in place and perform some trial test and use the cart as I would on a hunting trip. I travel to my hunt club typically over weekends and with the XCT Tool Kit and knowing the controller can easily reset the auto-cal then that may work best for me. I'm presently doing break-in runs on a new battery pack to prepare for the upcoming hunt season so a good excuse to see if the "Hunt" switch is my solution to the excessive solenoid clicks.

[Sergio]

I certainly understand, I like to work on these kind of issues without any expectation of anyone having to implement the ideas.

I enjoy posting when I have an idea or ask questions when trying to understand the variables that cause the problem instead of just fixing the symptoms.

The issue with the MCOR resistance and how Alltrax does the auto-calibration creates a problem for trying to occasionally by-pass the micro-switch.

Disabling the auto-calibration and using fixed limit values from the precision-throttle is not a good solution either as You would have a big dead spot on the beginning of the pedal travel when in hunt mode.

We also learned that jumping the two pins on the MCOR to test it on an Alltrax Controller may not always produce conclusive results and we should always guide the user to utilize the monitor screen in those cases.

From a systems design perspective, It is always better to eliminate the user as a critical component as that is typically the source of failure.

One last sketch I did at lunch, this one by-passes the Solenoid negative activation, but it does so with a self-reset circuit so the by-pass only stays in effect while the Key Switch is ON.

If You turn the Cart OFF while in "hunt mode", after You turn the cart back ON You will need to press the "momentary" push button again to latch the Solenoid if You want to go into "hunt mode" again.

Once the circuit is latched the Solenoid will not turn OFF even if the FNR switch remains in Neutral, only turning the Key OFF will reset it to "normal" mode.

K1 - 48v Relay:

https://www.mouser.com/ProductDetail...QaAg4pEALw_wcB

D1 - Diode (1N4007):

https://www.mouser.com/ProductDetail...xY3rLmCS1i8%3D

D2 - Diode (10A10):

https://www.mouser.com/ProductDetail...7oOwMisg%3D%3D

SW1:

Momentary Push-button.