Need directions on some wiring EVG 24v bike

[Cosmic]

As the title says, I'm trying to fix up my trusty old EV Global 24v ebike. It's an old bike, but it's still good!
It got a bit roughed up in my move from Utah to Oregon, but I think it's all good.
I used a bench top power supply to test the horn, and the motor, and both are working good. I reconnected the lights, throttle, and horn controls up to the controller, and got the controller hooked up to the power supply, and it all seems good. It's reading out as if it has a full battery, and I hear a relay click when I turn it on and off, and I think that's a good sign?

What I'm really confused about is how to hook up the motor leads.

The motor has these 4 wires, two of which are sensor wires, and that's pretty straightforward. They all quick connect into a junction box, and then from there I'm at a loss.

There's a blue and red terminal (both ring terminals) for passing power to the motor; but where do they go???
The controller is pretty straightforward; everything connects to it with tiny connectors, and then it has spade connectors that attach to the power terminals.

I'm at a loss as to where to connect the blue and red wires, and the service manual is seemingly no help. There's no place to connect the ring terminals except for the initial battery leads, but that'd pass 100% power to the motor at all times.

I'm at a loss as to where they're supposed to interface with the controller, which is the stock controller that came with it.

I can't find any diagrams or pictures online. Do any of you have a EV Global bike and could tell me how it's wired up?

 

[amberwolf]

My old breaks were something that broke in the move, so I've since gotten new ones. The old ones were magnetic switches, but these new ones are mechanical button switches. In any case, to exclude them from testing (assuming it's just a matter of if they're open or closed as far as I can tell) I've been conducting all my tests independently with both the brake pins both jumpered and with them both open to test all variables on open and closed brakes, and it hasn't really done anything noticeable.

You will still need to determine what brake type you need (NC or NO), and be sure the kind you have is that type. Otherwise it still won't work in normal operation when you get it working and get new batteries.

I looked at the schematic, and this is what I can tell so far:

I attached the schematic separately to this post as an image for reference.

The "logic" section (one of the daughter boards, AFAICT) is really the interlock board. It has some other things too. It lists these as inputs:

Interlocks:
KSI
Thermal
Brake


Cruise Control
Normal/eco
throttle


Then it also creates the 6volt supply (rather than 5v, for whatever reason, so your meter is probably fine).

It then otputs three LED signals, a green, amber, and red, which are shown in the Right Handlebar Controls to be be battery level, where red is too low, amber is not full, and green is full.


The KSI appears to be driven by the main relay control signal, and there is only one relay (other than for horn) so the click you hear when turning it on should mean the KSI input is satisfied. Based on the diode there, the KSI line probably goes to ground when active, so the system would operate if able to if the KSI line reads near 0V.

Thermal appears to be a switch based on the diagram. Most likely it is just one of those switches inside the motor that opens when the temperature rises above a certain point (probably somewhere close to boiling water temperatures). So it should read with a meter on any range as near zero ohms. If it reads OL it means it's open and the temperature is too high or the wire is broken. It probably does not read the actual temperature at all, unlike sensors found in motors today. As long as it makes a connection, then the system would operate if it were able to.

Brakes are NO (normally open) type, meaning if you aren't pulling the levers, the switches are open. This means that you can leave them disconnected and unjumpered and the system would operate if it were able to.


S

 

[amberwolf]

The FETs can be tested with the power disconnected and motor disconnected.

Set meter to Diode Test if it has this (looks like an arrow with a bar on the tip). Red lead on motor wire attachment point. Black on battery negative spade lug. This should read OL.

Swap leads. This should read some number, commonly between 400 and 800.

That means the FET isn't shorted or blown open, and so it "should" work if it's getting the right signals.


Fidning out if it gets the righ signals will require opening up the controller and finding the FET gate pin. WIhtout an oscilloscope you can only really check for the average voltage on the pin with and without throttle input. It should vary in voltage as the throttle position changes, with the meter set to 20VDC and the black lead on battery negative and red lead on gate pin.

 

[Cosmic]

I really appreciate you guys, you've been super helpful!
Unfortunately I haven't had time to do more work on my bike since I've been busy with my job, but I'll get back to tinkering with it in the next few days and report back from there.

Edit: oh yeah, I forgot to mention:
I've started using around 26v like you suggested, but I'm wondering if my power supply just can't pass enough Amps, so I'll look into getting new SLEDS for my battery soon, because the ones in it now are totally shot, and can't even hold a charge. Probably because I had them in storage so long.

 

[Chalo]

Don't buy new SLA batteries for a light EV. It hasn't been cost effective for years.

 

[amberwolf]

I've started using around 26v like you suggested, but I'm wondering if my power supply just can't pass enough Amps,

If it can't, the voltage will drop while it's under the load. You should see this on the voltage display on the PSU.

If the wires used to get power from the PSU are too thin, there can be enough voltage drop on those under load to cause a problem. Measure with your meter on 200VDC at the spade lugs on the controller. It should measure the same as the PSU's meter.

 

[Cosmic]

Don't buy new SLA batteries for a light EV. It hasn't been cost effective for years.

In my case, it probably is better to get lead acid for now. I already have a stock battery sleeve that takes two cheapo 12v lead acid batteries to make a 24v battery, and getting those two 12v SLA batteries only costs around $50. A Lithium battery would cost around hundreds of dollars. I know Lithium is the popular go to because it's light and more efficient, and can typically hold more capacity by volume; but it's certainly not cheaper in my case. I have about half the number of 18650 cells id need to *build* a battery, bur then we're talking the cost of the other half of the cells, a BMS, and any other circuitry and construction materials. My 3d printer is down, so I'd probably be better off buying a kit, and in the end it'll all be more expensive and time consuming than simply buying new SLED's; and I need a vehicle now, because my car got wrecked, and my only mode of transportation is the bus, which sucks.

 

[E-HP]

In my case, it probably is better to get lead acid for now. I already have a stock battery sleeve that takes two cheapo 12v lead acid batteries to make a 24v battery, and getting those two 12v SLA batteries only costs around $50. A Lithium battery would cost around hundreds of dollars.

If you've been happy with lead acid, then that's what matters. "Cost" over time takes into account initial investment divided by the discharged capacity, so it all depends on how you use the bike.

Lead acid would last forever (figuratively) if all you do is ride the bike slowly around the block each day and come home and charge it at a low rate. You wouldn't be closed to 50% discharge, you won't heat up the battery, and you're not leaving it discharged. Both lead acid and lithium ion will be affected by the discharge and charge rates, temperature, and depth of discharge, just differently.