Hi from hilly Sheffield

[sheffieldmike]

I bought a Conhismotor kit from ebay 36v 350w front hub. Its been trouble free for 3 years and very enjoyable though not quite powerful enough for our hills and my age.
Anyhow its gone faulty and I wonder if I can get advice please? The power comes in bursts of a second or less. If I release the thumb throttle and press again the same happens.
I have changed the throttle and the battery seems ok. Connections fine.
I contacted Conhismotor and he felt sure it was faulty Hall sensors which he sent me ($30) I replaced them but the fault is exactly the same. (No reply from China on this as yet)
I imagine then the controller has to be at fault. With alluminium the cover off there is a tiny flashing light that flashes continuosly. Anyone know what this could mean?
Been off the road several months and in dispair.
Thanks
mike

 

[Deleted member 4366]

If the light flashes continuously, it means nothing wrong - no fault detected. Different faults cause it to flash with a sequence of flashes.

First, you need to measure the battery voltage at the time it has the problem - like now. Report the results here, then we can help further.

 

[sheffieldmike]

If the light flashes continuously, it means nothing wrong - no fault detected. Different faults cause it to flash with a sequence of flashes.

First, you need to measure the battery voltage at the time it has the problem - like now. Report the results here, then we can help further.

Thats interesting thanks for quick response.
I have just been looking again and I cant get it to work at all now. The odd thing is that the battery terminals are constantly reading 40 volts (36v battery) on my meter but the 3 indicator lights on the battery panel are nil - just the red light.
I wonder, do the BMS ever go faulty ie. fail to deliver current or cut off?
When last used the charged battery was not lasting as long as it once did.
I am not sure how to proceed now.
Thanks so much for your help
Mike

 

[Deleted member 4366]

Sounds like a problem with the battery. charge it right up, and then measure its voltage. If it's below 41v, it's probably faulty.

 

[sheffieldmike]

hi
The Battery this morning is now reading, at the reminals, 39.5 v which must surely mean its ok? (36v battery)
As I said I cant get it to work at all now.
I just have tried connecting the battery to kit whilst on charge and it works but I still only get the one second burst.
Are there any other checks I can carry out? Puzzled about battery indicator lights.
I think the reason Conhismotor thought it was the Hall sensors was because the wheel did shudder at one point. I am still awaiting reply.
Thanks
mike

 

[Deleted member 4366]

hi
The Battery this morning is now reading, at the reminals, 39.5 v which must surely mean its ok? (36v battery)

if you know all the answers already, just carry on and don't waste our time. if you want to fix your problem, do as I say.

 

[trex]

I think d8veh is right, it seems the battery needs checking.
just a suggestion: try to discharge your battery into some light bulbs (eg 500W flood halogen) or bar heater - checking on the voltage every now and then.
When a fair amount has been discharged, put the battery back on charge. That will give you a pretty good idea if the battery has a problem.

 

[sheffieldmike]

I think I have readily confessed my ignorance and dispair and followed advice. ...The voltage has not dropped. When I said surely ok? there was a question mark ????? I am so sorry to have offended people on my first post.
I will find a way of discharging battery as suggested
thanks
mike

 

[Deleted member 4366]

I am so sorry to have offended people on my first post.

You haven't offended me. i just get fed up with people doing everything and telling you everything except what you need to know to sort the problem. You can save a lot of time, and get straight to the cause of the problem if you do simple logical tests.

the first test is for a duff cell in your battery. if you charge it up and it doesn't remain above 41v, you have a low cell that needs sorting. A low cell will cause the sort of problem you have, so it needs verifying or eliminating as the cause.

 

[sheffieldmike]

Problem update
Charged full but according to my meter only 40v it has dropped now to 38.5v
I tried to discharge (Thanks trex) but it will not even light a 12v bulb (Baffled with this!)
So D8veh correct about a battery fault.
(I suppose I was reluctant to believe since only 3 years old and I dont think I abused it)
Next step please?
Thanks very much for help very much appreciated
mike

 

[trex]

you need to open up the battery and locate the balance wires.
These wires go to each cell, one after the other.
Measure the voltage between the battery's plus terminal and each of the balance wire.
You should see 0V, 3.8V, 7.6V, etc, the voltage goes up by 3.8V steps.
If one is lower, then the cell it is attached to is likely to be faulty. Look also for tell tale sign of swelling. If you have a swollen cell, that cell must be replaced.
Do this first and post your result.

 

[Deleted member 4366]

One or more cells are not what they should be. As Trex said, you now have to go down to a cell level to find out what's going on.

If you show us which battery you have, we can give more specific help, but in principle you have to find the BMS, which is the PCB that controls the battery. On some Conhismotor batteries, it's in a separate box, otherwise you have to find it inside the case, usually under some shrink-wrap. You might be able to access the cells to measure them directly, otherwise you have to pull the multipin plug on the BMS and measure between the cell-pack negative and each pin. You can measure from the positive, but you'll be measuring down instead of up, so -4v, -8v, etc. The BMS has two thick negative wires: in and out. You have to measure from the in side because the out one might be switched off.

 

[trex]

...
The BMS has two thick negative wires: in and out. You have to measure from the in side because the out one might be switched off.

that's why I suggested to measure from the battery plus terminal, it's the common rail. Mike, the polarity does not matter much, swap the probes if a minus sign comes up on your tester.

 

[sheffieldmike]

you need to open up the battery and locate the balance wires.
These wires go to each cell, one after the other.
Measure the voltage between the battery's plus terminal and each of the balance wire.
You should see 0V, 3.8V, 7.6V, etc, the voltage goes up by 3.8V steps.
If one is lower, then the cell it is attached to is likely to be faulty. Look also for tell tale sign of swelling. If you have a swollen cell, that cell must be replaced.
Do this first and post your result.

All the cells look uniform to me, these are the RESULTS -
35.8
32.0
28.3
24.5
20.5
16.6
12.5
8.32
4.15

Thank you all again. Mike

 

[Deleted member 4366]

You're missing one. There should be 10. measure like I told you.. If that still only gives 9 results, take the battery positive as the 10th.

Those results are pretty bad. The one that's at 4.18v is stopping the rest from charging.

 

[sheffieldmike]

Hi Sorry d8veh, I saw your post only after I had done it.
There are 10 and the first is 0v next 4.15. etc
Thanks
mike

 

[Deleted member 4366]

Sometimes the first pin is a common ground. I think that the last cell is between pin 10 and B+.

Please measure the voltages like I asked you otherwise I can't help.

 

[trex]

your result:
cumulative V cell V
40 4.2
35.8 3.8
32 3.7
28.3 3.8
24.5 4
20.5 3.9
16.6 4.1
12.5 4.18
8.32 4.17
4.15 4.15


it seems that you have quite a few cells out of balance. The one that has 3.7V for example can't work with the one at 4.18V. It is possible that the weak cells (4.2, 4.18, 4.17 and 4.15) have lost most of their capacity and get overcharged too quickly and cannot be resurected. It may be time you buy a new battery.
d8veh?

 

[Deleted member 4366]

I'd need to know what battery it is to comment, plus, I'd like to see it measured the proper way so that i can make sense of the results.

 

[sheffieldmike]

I have measured again from the bottom left neg terminal (end of battery pic)
Along the block starting with red, I have-
20.6. 16.61. 12.44. 8.30. 4.13. 0. 3.87. 7.65. 11.37. 15.06

in case its not clear the battery is SHUANGYE 1109 YO102
Thanks for patience
If its a case of a new battery can you please advise as to what and where to purchase?
mike