2019 Gem EL XD Brainstorm

I find it unclear how much the encoder was turned.
It looks like it was in 180 then maybe 10 degrees more?

@Inwo @AssyRequired

I haven’t had hands on this frane size motor, and i can’t tell tell exactly form these photos posted previously .

How is the encoder wheel secured to the rotor shaft on this frame size? Press fit? Can it slip / rotate on the shaft?

Do the motor end caps use alignment notches where they mate with the frame / casing around the stator? In the past on certain brands / motor manufacturers, I’ve seen end bells get rotated slightly off, sometimes in opposite directions, from their original positions on the frame after in-hoise or field repairs, say end bearing replacements. With an internal encoder like this it wreaks havoc and can be hard to spot if you arent looking for it. Depending on design and parts, just a degree or two misalignment and the pickup is no longer perpendictular its at a slight angle.

Can that happen on this brand / frame size?

This one looks clean, probably no reason to have ever disassembled, and possibly 100% correct… but that’s viewing it as a civilian now. Myself having been exposed to and working with military equipmemt maintenance schedules many decades ago, I’ve seen schedules where things like perfectly serviceable end bearings, gearbox lip seals, pump and gland packing, etc are removed and replaced with new based on an hour counter and that’s it. Its not a “check this” its a “replace this, period”. And, you have magic unlimited money to do it.

This sounds like a joke, but it can be a real, often overheard conversation:

“So it doesn’t work at all after the service?”
“Must have been broken before we drove it in, sir.”
“Ok, buy a new one. Send this shitmissile to DRMS, let those jokers deal with it”
“We already cleared the bay. I just need your signature here please.”
“Excellent initiative! I see E-5 in your future.”

The movie Stripes wasn’t a comedy. It was a documentary.

This was US Army base fire dept auxiliary vehicle. Even a lowly golf cart can be classified priority mission critical if the description is worded right…

Not knocking the Army here, every branch had our own Derpy Derpalot stuff.

Many times, but not always, it was named “Lieutenant”, but I digress. And stereotyping is bad, according to 9 out of 10 Commanders surveyed.

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I could ship you the OEM encoder, or I can cut the tab and put it in the same orientation as the Amazon one to see if it has the same result. Could be an interesting test. I’m not great with connectors… so swapping pins might be out of my league lol.

For better reference. It did not work at 180 degrees. Very small window of degree change from this location before the motor cuts out.

Or, hear me out.. We try out a fancy new modded controller and see if that allows the OEM encoder to work as normal again. :laughing:. Would be interesting to see if a controller could actually slightly fail without a blinking light.

Why is this possibly so far down on the list of the possible root causes?

“When you absolutely want it dead, broken or pregnant, send the US Army”

You could check 2 of 3 boxes easly here…

Doesn’t matter. Signal is not timed to position. Signal only indicates speed and direction. Direction is sensed by either AB-AB-AB or BA-BA-BA. The Secon is very picky about signal quality and exact 90 degree shift between A and B. If the two halls in the new sensor are not set perfectly to the gear tooth spacing it effects the 90 deg phase shift. Twisting the encoder changes the hall spacing in relation to gear teeth. Picture turning the sensor 90 degrees from parallel to rotation! Both halls trigger at the same time. Equals zero degrees phase shift.

Do that. I’ll pm my address.
My money is on bad encoder replaced by bad encoder. The club car may use a different wheel or the controller may not use as tight specs as Sevcon does.
I’ve used these encoder clones myself, but maybe I was just lucky.

Thanks Dave.

“Jar Jar?”
“Yes other Jar Jar?”
“Its not an indexer. Its just an encoder. JUST. AN. ENCODER.”

Go insomnia.

ODtGrZ

Got my bench setup running. Tested two Amazon encoders OEM 614252 on box. Also X004FLKPFV.
They work over quite wide range of rotation.
Maybe you just got a bad one.

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How about this… Instead of wasting money on shipping, I’ll just cut my old sensor and do the test with that one.

Could not replicate with old OEM Encoder. So, I have a new one coming in. :+1:t2:

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@JarJarJava @Inwo @AssyRequired

Final update for the encoder. The new one came in today. I installed it, and it did the same old slow wheel move. I scratched my head… moved it around a bunch.. still nothing. I then put it on jacks, brought out the old broom… wedged it into the pedal and drivers seat, then got to work. Eventually… I was able to get the encoder to be recognized and seated it properly with the screw. It’s weird… almost like the controller needed to see a change in readings while motor was engaged to activate as normal. Now, it runs just fine. Encoder is screwed in as it should be at the correct placement/angle.

Now, I just need to get some brake pads that fit the front (any suggestions on aftermarket ones people use for these?), maybe some bigger wheel/tire combos, and eventually when I get some more funds - a modded controller :crossed_fingers:t2:. Inwo- I’ll be in touch once I see that as a possibility.

I want to thank everyone that was involved on this project. I would have had a rough go with that encoder without the gentle nudges in the right direction from you guys! I might actually be most surprised that the Bluetooth and speakers work lol… Small wins.. Sometimes a gamble pays off, with a little luck, good help, and a little tiny bit of skill.. The little FireTruck Gem that chugged along, says Thank you!

In conclusion? Poor quality encoders? I can rotate mine over a wide range, and motor runs fine.
Enquiring minds need to know. Do you have an extra encoder to send me on my label?
Alignment issue, or spacing from wheel? If your encoder works for me then it must be motor wheel or funky controller, yes?

Considering I got the encoder to work in the appropriate location, eventually, makes me think that it’s fine. I doubt I would get two bad encoders in a row. It my opinion it seems like a troublesome controller. Just listening to how the motor picks up speed, makes me think the controller second guesses itself during acceleration at times. I would take a video of what I’m talking about, but I feel like crap and I just don’t have the energy right now.

Maybe we can do some mods on this controller some day and your computer will say “someone did some crazy stupids mods to this thing”, and we will know for sure lol. Wish I had a scan tool for this beast.

Makes sense. The encoder inputs are extremely sensitive. Very high frequency. 64ppr each channel up to 9,000 rpm and can’t miss a pulse. AI told me that car will go into limp mode if one channel goes out while driving. Not that I believe it!

If you are one the fence about ne controller, I need one tested. Play a while and return it is fine with me. I have one going out in the next few day, but have concerns that he can’t follow simple schematic.
The wire mods are additions, and old controller will plug and play. Going back to stock.