Blue "Electric Lock Wire" on Conhismotor Controller

[eHomer]

Smee again....

A few months back I bought a Conhismotor controller with the LCD panel with 5 levels of PAS.

I couldn't get it to work, and despite a lot of help from people on here and Dave's kind assistance in also checking it for me, it still wouldn't spin the motor, so it looked like a faulty unit. Conhismotor were then very good in sending a replacement controller.

That however, had exactly the same apparent fault and symptoms, ie, it powered up, and the display worked in every respect, except for actually spinning the motor. The chances of two faulty units seems slim to me, so I'm still tinkering with it.

Now to the point of the thread title, on the Conhismotor site, they refer to the thin blue wire from the controller to the panel as "Blue Wire: Controller electric key lock wire" , and yet in the 5 wire connector, there is no corresponding wire linking it to the controller, it's just disconnected. When the controller is powered up and the display lit, there is full 36v battery voltage on it (around 41v), but that is not then connected back to anything.

Here's the Conhismotor page: http://www.conhismotor.com/ProductShow.asp?id=309

Mine's actually the 750w controller, but the connections and panel are identical.

I'm still curious as to that wire's function. The controller has the more standard red/yellow pair of wires that are normally connected to a lock switch, which I have tried both shorted out and disconnected. In fact, when they are connected, a faint "click" can be heard from the controller, indicating that something is operating correctly in there.

So should the blue "lock wire" be connected to something else ? Conhismotor normally supply the full kit with a combined throttle/ignition switch, and I'm just using a standard thumb throttle, which I have tested on another bike.

As always, any ideas or suggestions gratefully accepted !

 

[Deleted member 4366]

The red wire going to the panel is 36v and is used to power the panel. When you press the power button, it's latched to the blue wire, which sends the 36v back down the blue wire to the controller to power it. All the Chinese LCD and LED panels work like that. I don't know why they call it the lock wire because it would be better to put an ignition switch on the red one.

You can test whether the 36v back to the controller is active by checking the 5v throttle or PAS supply (red and black). Once the 36v arrives back at the controller, it's cut down to 14v for the FET switching control and then again to 5V for the CPU and sensors.

The main battery wires go direct to the FETs that do nothing more than switch them on and off directly to the motor phase wires. The main CPU works at 5v, and fires out pulses of 5v to transistors, which then switch the 14v to the FETS, so the FETS fire at the same time with 36v as the controller does with 5v.

 

[eHomer]

Thanks for the reply Dave.

I've now been out to the garage and tested the voltages you mentioned, and also tried an interesting experiment !

Yes, when the panel is powered up, I get 4.5 volts on the red wires of the throttle and the pas connector.

I then had a thought, the Conhismotor lcd panel is identical to the one you sent me with the controller for the MXUS motor, so I swapped those over, to test the Conhismotor panel on it's own, and it worked fine.

I then looked at the wiring between the MXUS controller and the LCD panel, and that one did have a blue wire connecting the LCD's panel blue wire back to the controller.

So I tried carefully easing the blue wire out of the 5 way connector, to disconnect it, as it is in the Conhismotor wiring.

I then got exactly the same result as with the apparently faulty Conhismotor controller. Everything appeared to work on the panel, but the motor doesn't spin.

I then tested for the red wires on the PAS and throttle, and I got 4.5v on them, just like on the Conhismotor controller.

So as the MXUS controller shows exactly the same readings and fault as the Conhismotor controller when the blue wire is disconnected, I'm still strongly suspecting that it should be connected back to the controller, as it may be some sort of signal that the bike is "unlocked" and ready to go.

I know it means that the connections that Conhismotor would be amazingly incorrect, and that no similar units would work without a blue wire running back to the controller, but what point would it be connected to in the controller ? It has 41 volts on it.

 

[trex]

on some LCDs (like the King Meter), the lock signal is optional output from the LCD.
Try connecting a 10k resistor between the blue wire (controller side) to ground. It may get your motor going.

 

[eHomer]

Thanks for the suggestion Trex.

I've rummaged around in my parts box and found two 20k resistors, so I tried those in parallel across the blue and black, but no response from the motor still.

 

[trex]

did you check the voltage of the blue wire on the working MXUS controller?

 

[Deleted member 4366]

Yes, my memory slipped again. IIRC, I checked my working Conhismotor controller, and the blue wire wasn't connected either, so the controller must get its power from the battery wires, which would explain why mine still works when switched off. I have the re and yellow key lock wires bridged.

If you've still got them open, could you take some good photos of both sides of both controllers, so that we can see what's what - particularly where the blue wire goes on the small controller.

 

[mountainsport]

Hello eHomer did the LCD control panel come with a manual, if not do you know where to down load this from? Thanks.

MS.

 

[eHomer]

Hello eHomer did the LCD control panel come with a manual, if not do you know where to down load this from? Thanks.
MS.

I do have a Conhismotor PDF with all the instructions for the LCD panel, but I can't find a link to it on the web. I thought someone on this board had given me the link in a previous reply to me, but I've searched and I still can't find it. Conhismotor did send me the PDF file direct, and I tried to upload it to this forum as an attachment, but it exceeds the maximum size allowed. I tried to send it to you as a private message attachment, but that wasn't allowed either. If you can send me a PM with your email address, I'll email it to you.

Trex - I'll check the voltage on the blue wire of the working MXUS setup,

d8veh - I'll open both controllers and take detailed photos as suggested, it'd probably be quite interesting to compare them anyway, albeit one is for 350w and the other is for 750w.

 

[eHomer]

Here's the photos of the inside of the two controllers.

The blue wire from the LCD panel on the MXUS controller is connected to VCC on the board, and brings 41v back to it from the LCD panel. (When disconnected at the 5 wire connector, there's 41v on the panel end, and zero on the controller end.

There's no corresponding larger marker point on the Conhismotor controller.

 

[trex]

Just to confirm:
- on the MXUS kit, the blue wire is connected to Vcc on the controller side, suppling 36V to the electric lock input of the LCD panel.
- when you unplug the blue wire on the controller side, the MXUS motor does not work

Question:

does the votage on the blue wire LCD side show 0V when you disconnect the blue wire controller side?

Suggestion:

If it does, then on the 750W controller, pull up the missing blue position (controller side) to 36V with some resitor.

 

[Deleted member 4366]

It's the other way round. The blue wire is an output from the panel. It's latched on when you press the power button. Normally, it goes to the controller, through the big resistor to the 14v regulator, and then on to the 5v regulator.
It appears to do that on the small controller, in which case the 5v on the throttle will only be present when the blue wire is active.

The large controller is different. I can't follow the tracks from the photo, but there should still be 36v on the big resistors, 14v from the first regulator and 5v on the throttle.

 

[eHomer]

Dave's answer is the result that I'm getting.

The blue wire from the LCD panel goes up to 41v when the panel is switched on, so it's trying to send it back to the controller. When the blue is disconnected, it leaves 41v on the panel wire, and nothing on the wire to the controller.

On the MXUS setup the blue is connected to VCC.

On the Conhismotor setup, the blue isn't connected back to the controller at all.

The Conhismotor controller does have just under 5v on the red wires of the PAS and the throttle.

I'm not as well up as you guys on the circuitry, so I may be clutching at straws here, but it seemed strange that the MXUS setup has exactly the same fault symptoms as the Conhismotor when the blue wire is disconnected.

I'm wondering if anyone on this forum (or the ES forum). has heard of anyone who has bought the Conhismotor "new" controller with LCD panel and got it working ok ?

As this fault is exactly the same on two identical Conhismotor controllers, I'm wondrering if the controller was adapted to work with the new LCD panel, and maybe they tested them on a factory jig that's not exactly the same ?

 

[Deleted member 4366]

On the small controller, the 5v goes off when you disconnect the blue wire. It doesn't with the large one, so they're wired completely differently. The large one has the additional red and yellow wires, which Iused to think were also necessary to connect to bring the 36v to the controller, but I'm not sure now. The CPU must be sensing something else to prevent it from giving power. I have the same controller on my GNG, where it works perfectly. Geoff9 also has one (250w version), which worked straight out of the box.It has exactly the same wires.

 

[eHomer]

......The CPU must be sensing something else to prevent it from giving power......

I think that's it, in a nutshell Dave.

As you say, the big controller has the red/yellow pair, whereas the small controller presumably monitors the blue wire back from the LCD to serve the same purpose.

It adds suspicion in my mind that the large controller and the LCD weren't originally designed for each other, unlike the small controller and identical LCD panel, which doesn't have the red/yellow lock switching.

 

[justinlterrell]

Im having a similar issue. Im rewiring a ebike controller and my dumb self assumed i didnt need a few of the wires, so i desoldered them from the controller...(one wire i took out labeled "electric door lock - must be connected).
I swore i took pics of the wire removals just in case i needed to resolder them. I checked everywhere for the pics but to no avail. I usually always video or pic out my electronics assembly/disassembly.

So now im in a pickle. Ive searched the internet for photos or anything to help me where this wire needs to be located on the board. Can anyone help? Heres some pics. The orange wire is what needs to be resoldered and connected. It say it needs to be connected to voltage but do i just connect the door lock wire directly to the battery? 60v battery? Any help would be great. This site is the closest ive found to any kind of answer....
The marker marks where i think it may or may not be, but not 100%.

 

[wheeliepete]

You are right, the orange wire needs battery voltage to activate the controller, you can run it through a switch or connect straight to + battery connection, but I can't identify where to solder it to the board. Some of your photos are a too fuzzy. Look for a connection marked Lock, LCK maybe?

 

[wheeliepete]

I will have a look at the spare controllers I have, one I know has a lock connection on it. Next time cut the wires close to the board leaving a bit of insulation attached

 

[wheeliepete]

Had a look at my controller, but sadly no markings at all on the board either side where wires are soldered on.