Problem with controller (maybe).

[Trevor Holloway]

My Sunlova kit has been working fine for the lastfive months but about a mile from home last night something has gone wrong and I was wondering if anyone has any ideas.

I was riding along with the throttle power on and everything cut out including no lights on the throttle display.
Tried the usual :
Make sure battery was securly in place,
Check connection to motor.
Switched off and on again - success ie the lights came on showing full battery.
But when the pedals are moved or the throttle is turned on there is only a single pulse to the motor and it cuts out.
Turning the main switch off and on starts the cycle again ie one pulse only then no lights etc.
Have disconnected the pedal sensor and motor and the same still happens therefore ruling out a short in the motor.
Fuse in battery is OK and there is still 3/4 charge in the battery.

Any suggestions ?

 

[NRG]

You either have a poor motor phase connection, hall sensor connection (if fitted) or at worse a failed phase in the controller....check all the connections and spray if necessary with some WD40.

 

[Trevor Holloway]

Would this still be apparent if the motor is disconnected ie only one puls and it still cuts out ?
As the motor has only three connections I do not think I have any Hall sensors (thus eliminating that problem).

 

[NRG]

OK if no Halls then it's most likely a phase connection problem or one of the phase drive circuits in the controller has failed. You could try and meter each phase wire to see if there is a short using a multimeter. Put one probe on the negative battery feed to the controller and use the other probe on each phase in turn checking for a short. Any short means a failed controller.

 

[banbury frank]

Hi I find that the Is the main problem with electric bikes the environment is

so aggressive bumps potholes vibration not the faults off the makers


If it still continues if you purchase a new controller from sunluva it should not be very expensive ask for a wiring diagram

I very much doubt the Motor that just leave the battery again been bounced all over the place not you fault that's what you bought it for

Loose dirty connectors Main problem

As we see more and more electric bikes on the roads

we hopefully will see local bike shops with the spares and skills to diagnose and repair electric bikes

Frank

 

[Deleted member 4366]

Sounds like a short in your controller is overloading your BMS. The only other thing worth checking is the wiring around the battery switch if you have the type that has the switch on the plastic bit that stays in the rack. You should remove the battery, unscrew that plastic bit from the rack (4 screws) and take it apart to look inside at the wiring to the switch, which on mine was very feeble. While you're there you might want to solder in thicker wire. While these bits are off the bike and open, you should be able to connect them and wiggle and shake the various bits to see if anything causes a power cut-off.

 

[John L]

My Sunlova kit has been working fine for the lastfive months but about a mile from home last night something has gone wrong and I was wondering if anyone has any ideas.

I was riding along with the throttle power on and everything cut out including no lights on the throttle display.
Tried the usual :
Make sure battery was securly in place,
Check connection to motor.
Switched off and on again - success ie the lights came on showing full battery.
But when the pedals are moved or the throttle is turned on there is only a single pulse to the motor and it cuts out.
Turning the main switch off and on starts the cycle again ie one pulse only then no lights etc.
Have disconnected the pedal sensor and motor and the same still happens therefore ruling out a short in the motor.
Fuse in battery is OK and there is still 3/4 charge in the battery.

Any suggestions ?

Hi Trevor

I'm not sure if this is entirely relevant but my battery died for a second time last week. I contacted sunlova and they reacted very quickly. They told me that my replacement battery and the original controller were mismatched causing the bms to blow (or words to that effect). So they have sent me another new battery and a new controller. Hopefully I'll have them on Monday.

So I think there may be a problem with the controller (the battery that came originally also failed in the same way). Sunlova seem to be getting a few returns and seem serious about addressing the problem. Maybe you could contact them to see if they can help.

John

 

[John L]

Sounds like a short in your controller is overloading your BMS. The only other thing worth checking is the wiring around the battery switch if you have the type that has the switch on the plastic bit that stays in the rack. You should remove the battery, unscrew that plastic bit from the rack (4 screws) and take it apart to look inside at the wiring to the switch, which on mine was very feeble. While you're there you might want to solder in thicker wire. While these bits are off the bike and open, you should be able to connect them and wiggle and shake the various bits to see if anything causes a power cut-off.

Yesterday I dismantled the battery switch housing and I agree the connections to the switch are very light. I was looking to see why the switch no longer works with the new battery I got and discovered that the current flows through the outside connections of the plug and socket (hope that makes sense) which bye-passes the switch. I rewired it so that the switch is connected up again (so now I'll have two switches connected - one at the battery and one at the switch housing). The switch on the battery isn't very convenient.

John

 

[banbury frank]

I Find that most battery's out there that have a key switch the contacts are very poor Just light brass no coating so what I do is fit a 12 volt 30 amp relay taping off the BMS 13 volts with a 3 amp in line fuse for safety

I find on EBAY item number : 160364348442


Then the switch only has to cope with very low amps Big difference in power throughput I find it is best done from new

And

Frank

 

[Trevor Holloway]

Battery and controller going back for swapping.
Higher power controller not in until early March so will have to ride unpowered for a couple of weeks
Prompt response from Sunlova as usual.