Running without Hall sensors

[Alimages]

Hi. I've got a Chinese kit from Elifebike fitted on my Giant MTB. I've been experimenting with the wiring and I've noticed that the motor seems to run fine without the Hall Sensor wires being connected. Is there any reason that I need to connect them if it's all running OK? Or is it likely to cause long term damage? I just like to keep things as simple as possible. Can anyone shed some light? I'm assuming that the controller I've got is equally capable of running with sensors or Sensorless? As you can probably guess, there aren't any decent instructions with the kit. Thanks.

 

[NRG]

No and no... Some motors have the hall sensors and are used for positional feedback to the controller, the benefit is smoother startup and depending on application more power. However, hall sensored motors can be used with no hall controllers without ill effect. Some controllers are compatible with both types of motor so if its running now you will be fine.

 

[Scottyf]

By the sounds of it you have the option of running sensor or sensorless.

You don't need the hall sensors if the controller is capable. However running with Halls should give a more fluid and smooth ride. Espcially from the lower rpm range. As the controller isn't guessing which phase to push current through.

 

[Deleted member 4366]

+1 to Scotty's comment, plus: In theory the motor will be slightly more efficient running with hall sensors, so, if you have them and can use them, do so, otherwise no harm will come if you run sensorless.

 

[Alimages]

Thanks everyone for the quick response! What a brilliant forum.

I suspected that I could run without the sensors connected but I don't have the technical expertise to be certain. I just didn't want to damage anything.

The kit and bike have been brilliant so far, apart from this morning when I cycled to work in a complete downpour. 40 mins in which I could not have got any wetter even if I'd jumped in a river! The motor started playing up in the final mile or so, cutting in and out and even feeling like it was resisting me at times. All the wiring was nice and dry and the controller didn't get wet. My first thought was the thumb throttle but when I disconnected the Hall sensor wires, as soon as I could have a 5 min inspection at work it all worked perfectly. Plug sensors in again and it was a bit stuttery and hesitant. I assume it might all dry out and work again with the sensors connected. Tested at lunch (Without Sensors connected) and seemed fine. Will give it the big test in about 5 mins when I set off on my 12 mile commute home. Thanks again for your help.

 

[Scottyf]

Rain can cause issues on none water proof connections.
I'm sure it was just a bit of the throttle signal getting a bit of dodgy feedback. Just be careful no water gets to the controller.

Motors are generally pretty water tight and the same with controllers so it's usually some exposed connection that is usually the culprit!

 

[Alimages]

More problems! After a successful and dry ride home I thought I'd solved the fault. After dinner I took it for a final test up a local hill. Half way up the whole system went dead. No lights on the thumb throttle or anything. Stopped, checked the battery connection still nothing. Turned it of at battery and then back on and it all came back to life. Set off ok again until full throttle and then everything stopped again. Same thing happened 2 more times.

Got home and tried to charge the battery. The smart charger led was green straight away so it didn't try to charge. Now it seems that the battery thinks its still fully charged? It won't accept any more input from the charger. It obviously can't be because it has done at least 26 miles since last charge. Have I got a bad internal battery connection? Or what else can it be? Its a 36v "headway" pack from elifebike.com. Should I open it all up and have a look?

 

[NRG]

It could be a poor battery connection. The cutout symptoms you describe are similar to hitting the low voltage cutout of the controller, this is happens when the battery is nearly empty and any load placed on it takes the voltage below that of the controller cutoff.

If there is no connection between charger and battery then the green light will come on immediately, so it appears you have a flat battery and a poor connection somewhere in the charge connection...

 

[amigafan2003]

More problems! After a successful and dry ride home I thought I'd solved the fault. After dinner I took it for a final test up a local hill. Half way up the whole system went dead. No lights on the thumb throttle or anything. Stopped, checked the battery connection still nothing. Turned it of at battery and then back on and it all came back to life. Set off ok again until full throttle and then everything stopped again. Same thing happened 2 more times.

Got home and tried to charge the battery. The smart charger led was green straight away so it didn't try to charge. Now it seems that the battery thinks its still fully charged? It won't accept any more input from the charger. It obviously can't be because it has done at least 26 miles since last charge. Have I got a bad internal battery connection? Or what else can it be? Its a 36v "headway" pack from elifebike.com. Should I open it all up and have a look?

What's the voltage of the battery?

 

[Alimages]

Hi amigafan. It's a 36volt. One of these.
36V 10AH Headway 38120 LiFePO4 Battery Pack - Elifebike Online Store

I haven't had a chance to check it with a meter recently but when I installed it at first it was reading something like 39v.

 

[Alimages]

Thanks everyone. I've posted another thread call "video diagnosis" which might answer your questions.