Controller for Mac Hub

dogfood

10 µW
Joined
Feb 9, 2014
Messages
6
Location
Northeast Georgia
Hi,
I have an old ebike from the 20teens I am trying to rehab. It's an old Em3ev (48V Mac 12t rear hub) kit and the controller failed (if that wasn't the original problem, it certainly is one now). The battery seems to be charging fine, and the hub motor was strong on its last ride (and was not ridden hard, though it has survived several NYC winter commute seasons). The switch and throttle probably need replacement from sitting in the elements.

The question is: Can I still find a controller that will plug and play with one of these Macs?

New Em3ev said to try Lyen and I haven't heard back. I bought a controller from Luna a few years ago, but I didn't know what I was doing then either, and it's for a Cyclone motor. I have a functional knowledge of wire splicing and household AC, but this whole "thing" (gesturing at the rat's nest) is a little overwhelming. I found a wiring diagram so it's not impossible...

Another question is: Is it worth it? I'm one component from just getting a new kit--if either the battery or the hub, old as they are, fails then I'm not sure it's worth splicing a bunch of tiny wires to salvage. If my sole purpose is the ride, I'd definitely buy an easy front wheel conversion, but there is a scavenger in me who wants to see this old and potentially good stuff put to use.

Third question(s): So, say I can't find a plug and play controller, what's the best way to test when you are starting with all variables? Breadboard, or wirenuts? What kind of connectors do you guys like for testing purposes? Is there a set that can deal with all the different gauges?

Look at my baby! Isn't she sweet? Goose, a.k.a. the Shambler.
 

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Is that the same bike as this?

What specifically does the system do or not do that leads to failed controller diagnosis? (I ask because there are things that can appear to be controller issues that aren't, and would like to make sure you get the right part the first time).


FWIW, a battery ages just sitting there, probably faster the higher it's charge level when "parked". So if the battery is ~ a decade old, it is likely to have at least some capacity and performance loss.


By Plug-and-play, what exactly do you mean? Just that it will plug right in, but ok with a little setup of controller parameters? Or literally just plug in and go with no setup or tweaking?

Which connector(s) do you have?

If you can't find a controller with the right connectors, you can move those over from your existing controller. Best way is if you can solder them directly to the controller PCB in place of the originals, but if not, you can splice them in various ways (the best of which is properly crimped barrel splices, staggered so none overlap with each other to prevent possible shorts and lessen thickening of the splice area making it easier to waterproof if necessary).

The MAC has been sometimes found to be harder to drive correctly, depending on the speed you need to go with it, because of the high ERPM from it's pole count and gearing and internal RPM).

It's likely that the KT series of controllers will work with it, or the Lishui; not sure which would be better or any guarantee that either will, but depending on model number both have decent user-customizability and both have open-source firmware available for them to replace the OEM FW if that helps improve functionality.

What controller do you have for the Cyclone? If it isn't in use, you may at least be able to use it to verify functionality of the rest of the bike, battery, etc.
 
Buy yourself a cheap sensorless/sensored controller from Greentime/EvFitting and they have the wires clearly labeled right on the wire for you to document and take pictures of for future reference. If your battery can handle 40a, then get a 48v 30a or 35a controller. Otherwise your guessing with the rats nest of wires, which you may be able to tell what the wire is by what the pcb label says where the wire is on the pcb board.
 
Thanks for the replies!

@amberwolf - Yeah, same bike! What a trip, seeing that old message. I don't remember how I solved that problem all those years ago but the battery fully charged gives me 53V.
As to the original failure, I brought the bike out of storage a few years ago, charged the battery, and rode around successfully for a minute or two and then it quit. Motor stuttered and then nothing. I must have just assumed I had blown a fet, because I opened the controller and tried unsuccessfully to replace one.
So yesterday I decided to give it a shot and hook up the cyclone controller. I cut off the old connectors and spliced them on the new controller and I think I got everything hooked up. I bench tested my throttle and its good (0.8V-3.8V~). I have 5V at the red hall connector wire, and I'm getting oscillating voltages at the little YGB wires when I turn the wheel. It's not as clear cut from 0 to 5V like you see in the videos. Sometimes it jumps up to 20V! I attribute that to either my setup or my multimeter being bad. There is oscillation, though.
However, it won't run. When the phase wires are hooked up with matching colors I give it a little throttle and get no response, but the phase wires get noticeably warm! Going through the colored phase-testing chart that's around here give me little growling noises and jumps, but no improvement, no definitive spin and the other settings don't seem to heat the phase wires as much.
So now I think it's the hub. A hub failure can cause a fet to blow? I might need a cassette remover tool to proceed.

@calab , thanks for the suggestions. Are those found on AliExpress or is there a domestic distributor?

D
 
From some of the old threads about MAC motors it seems you can use a KT S12SN - but it must be the N model.
 
So yesterday I decided to give it a shot and hook up the cyclone controller. I cut off the old connectors and spliced them on the new controller and I think I got everything hooked up. I bench tested my throttle and its good (0.8V-3.8V~). I have 5V at the red hall connector wire, and I'm getting oscillating voltages at the little YGB wires when I turn the wheel. It's not as clear cut from 0 to 5V like you see in the videos.
because the halls depend on the pullups inside the controller for anything other than a 0v output, electrical noise on the signal lines between them can cause all sorts of minor variation in the signal itself, worse the faster the speed is (or the higher the motor phase currents in some cases).

(motor halls don't output any voltage, they only ground the voltage supplied by the controller when a magnet passes them, usually latching to ground as the first passes, the next turning the hall off so the signal floats up to the controller's pullup voltage on the hall signal wire).


Sometimes it jumps up to 20V! I attribute that to either my setup or my multimeter being bad. There is oscillation, though.
If you're getting high voltages on the hall lines, there's a good chance there is a short in the motor cabling allowing phases to touch hall signals, and that can easily blow up controllers (and the halls, throttles, anything else on the 5v line).

So first I would examine the motor-to-controller cable, especially at the axle exit, for damage of any kind. If there is any abrasion or deformation on the outer cable jacket at the axle exit but not exposed wire, it could still have internal damage to wire insulation allowing a short under some conditions.

If there is any corrosion on the phase/hall connector between motor and controller, that can also allow connection between phases and halls.

If it's a problem that does not affect the phases themselves, you might be able to use a sensorless controller, but you'll probably always have to start pedalling and moving forward first before the motor will start properly. (my experience with geared hubmotors and sensorless controllers is that they work more smoothly this way).

Otherwise as long as the halls actually work, the cable can be replaced or repaired to get the motor working again.

However, it won't run. When the phase wires are hooked up with matching colors I give it a little throttle and get no response, but the phase wires get noticeably warm! Going through the colored phase-testing chart that's around here give me little growling noises and jumps, but no improvement, no definitive spin and the other settings don't seem to heat the phase wires as much.

If it won't operate at all in any phase/hall combo, offground with no load, just a teensy bit of throttle, and given the other controller failure, then the most likely thing is a problem with either the connection between controller and motor, or the motor itself.

With the right combo, you should see the motor start spinning quietly at very low throttle under no load (offground), or at least hear it spinning inside the case even if the wheel doesn't spin (that's normal, just means its going backwards and not engaging the clutch to spin the wheel), and measure very low (1-2A probably) current from battery to controller even as you increase throttle to full and the motor keeps spinning.

I don't think you need to remove the cassette to open the motor. Pretty sure it's just the phillips screws on the cover side. Once open there may be snap rings (jesus clips, etc) securing parts onto the axle inside. This thread has some info about it
and there are youtube vids about the GMAC (same motor but locked clutch) and other stuff here:
 
Update:
There was water in the motor. The grease was a little like cottage cheese. Didn't see any obvious problems with the wiring. The hub motor covers were super tight, I don't know if they're supposed to release the bearings but they didnt, so a gear puller worked on one side, but I had to use the hammer on the other side. I beat the rotor (or is it the stator?) -the center part with the axle and circuit board, ahem, I beat it out with a hammer because I'd rather destroy something than be confounded by it. There was one retaining ring I missed, so I ended up gouging the center gear. So I assume it's toast. It's for the best as I'm replacing all that wiring and getting through the axle didn't look fun.

Can you find replacement inside parts? I have this nice rear housing and freewheel.
 
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