throttle keeps failing

Hi

I got a china escooter ebike with a 48v 500w controller. I recently replaced the controller and what happens is that when it stutters as it goes forward. Sometimes from a stop, it would stutter a bit and then proceed forward.

Its is during this stuttering that the throttle fails. It seems like its burnt and it would work with a new throttle, only to burn again.

I have thought that it could be a short in the wiring link from the controller to the throttle so I rewired the three wires and the same thing happens. I have replaced with another controller and eats another few throttles.

yesterday, I lost 2 and today one throttle.

what could be the problem?

Incompatible controller ? Short circuiting of other wires ( not the throttle)? is that even possible? I can rewire it but it takes a lot of effort.

What should I do? I do not want to replace another throttle only to have it damaged the same day.

thanks

Sounds like the low voltage regulator inside the controller is not regulating, and spikes are getting thru to the hall sensor in the throttle, damaging it.

If you have a 5Kohm or similar potentiometer, try using that instead of the throttle, just for a wheel-off-ground test, and monitor the 5V throttle line and ground, to see what it's putting out under different conditions. You can use your brakes lightly to simulate a riding load.

I would like to also add that it would be working for 1 mile or 2 and when I reach a stop light and turns the throttle when the light goes green, thats where it just wont work.


It is beyond the bike repairers here who will simply ask me to change throttle and it would work, until a mile or two away. I do not mind buying a new controller if you think its the problem. I can buy a potentiometer too but prefer to just replace what could be the problem. Or should I buy something that would arrest the surge in voltage? Is there even such a thing, I know nothing about electronics. I sure hope it not the motor. Any chance that its a short somewhere in the cables of the bike?

Just an update, I changed a new throttle and a controller and the same thing happened. What is not replaced is the motor and the wirings to the batteries.

Something is burning the throttle. It was working and a few miles later it just stopped after I stopped for a red light. I connected the wires without the throttle and it works.

What could be the issue here? battery or motor?

Couple of possibilities...

First off this might be a dumb question, but are you sure the throttle is really getting damaged? Just want to make sure... if you turn everything off wait 5 minutes and reconnect the throttle you are getting absolutely nothing, but if you connect a different throttle it works for a couple miles?

One idea occurs to me - you might have a phase wire between the controller and the motor with nicked insulation, touching the frame of the bike. This would raise the voltage potential of the frame of the bike and that could fry the throttle, if it (or the controller) was grounded or partially grounded to the bike. You could physically inspect the motor wiring where possible, and also use a multimeter to see if there is voltage present on the frame of the bike (frame to battery neg?), while the motor is going.

The controller could have a bad voltage regulator which is damaging throttles, but now since you have already replaced the controller and are seeing the same thing, that scenario does seem unlikely. Another similar possibility is that the replacement throttles you are using might be somehow incompatible with the controller. Again this would be a good place to use a meter to ensure that the controller is putting out +5V to the throttle and the throttle is returning a voltage of around 1V-4V (depending on throttle position) to the controller.

Basically what he said. ^^


Neither the motor nor battery could directly cause a throttle to fail. Something else is happening:

--wiring harness is damaged somewhere
--wiring from controller to throttle is incorrect (not likely, if it's working at all)
--the throttles are not really compatible with the controller for some reason (like maybe it uses more than 5V to run the throttle with).
--controller is not designed correctly, or damaged, and is not regulating the 5V to the throttle.

thanks for the pointers. The throttles are damaged I tried them days later and it would no longer work. My throttles are piling up.

The voltage on the throttle wires tested within range at 1 - 4 and under 5v. this was what the local bike tested for too and I tested at home and its the case.

This could be possible and the frame is attached to the controller with a stainless bolt. I can put a rubber mat under it and then secure it with zip tie or silicone to avoid the metal. I will check all wires and I notice that the 5 wires are rather thin.

I got the shop where I changed the throttle tell me that in his 14 years in China, he has not seen something like that. It is weird and usually this would not happen.

Do you think that it is the wiring to the lights and brake lights and speedometer, signaling lights etc may cause this as well?

I will check the wirings. I am glad to hear that its not likely to be the motor. that s gonna cost. Faulty bikes are really depressing.

I have a Ebike motor controller hall phase throttle tester a while back ut I havent figured how to use it.

If it did the same thing with another controller it's obviously not the throttles or controller. You've got a short somewhere else, so you need to trace all of the wiring, from the battery to the motor, and if you find nothing then check from the outside all the way to the wire terminations inside the motor. It doesn't sound like a battery short unless a loose wire is flopping around, so my money would be on the motor wires where they enter the motor, since that's typically the easiest place for the damage to occur.

Are you sure the throttles are actually dead? I recently had some kind of short in my motor harness that only reared it's ugly head as things warmed up, and the symptoms were similar to yours. I'm sure had I thought it was a throttle and changed it, the time to change it out would have cooled things down making the new one work until a mile or so down the road when the problem area warmed back up. My issue was even more prominent when starting from a stop.

i checked the wires from the motor to the controller up to the point it entered the motor and it is fine. I did not open to motor casing yet. The wires to the lights and power cutoff is rather loose, so I had it rejoined. One thing I noticed is that when the head lights are on and the throttle is turned ( yet another throttle, this time from an old bike) the lights would dim a little and if i swing the handle left with some strength, it would sometime blink. I will test ride it to see how it goes.

I have not checked the battery to controller because it is hidden by the case.

stone said:

The wires to the lights and power cutoff is rather loose, so I had it rejoined. One thing I noticed is that when the head lights are on and the throttle is turned ( yet another throttle, this time from an old bike) the lights would dim a little and if i swing the handle left with some strength, it would sometime blink.

Click to expand...

Sounds like you may have a janky wiring harness. A damaged wire anywhere in there -- perhaps even inside a multiconductor cable, caused by kinking, repeatedly bending or crushing it -- might have the potential to fry your throttle, by momentarily exposing any of the throttle wires to +12V/-12V lighting power if present, or +48V, etc. I would suggest further inspecting all the wiring and perhaps replacing/rewiring any possibly damaged wiring harness(es)...

I tried rejoining the wire and it didn't give me any problems yesterday. I too actually had the controller placed on a rubber mat and insulated from the frame. I will change the wirings but I cannot find multicolored for sale here. Cam I use Ethernet cables from network cables for 5v connections?

You guys may already know this, but for info, I just found out that the throttle has an 49e chip magnetic hall sensor so I can actually buy that to replace the burnt one.

Was able to test the bike last couple of days. took it out for a ride yesterday and today. The wheel got heavy and sort of locked a while while it was moving. Then it just would not move and the motor felt sluggish like theres a kind of resistance. Its able to turn completely but it takes effort. What could be happening now? I fried a motor?

stone said:

Was able to test the bike last couple of days. took it out for a ride yesterday and today. The wheel got heavy and sort of locked a while while it was moving. Then it just would not move and the motor felt sluggish like theres a kind of resistance. Its able to turn completely but it takes effort. What could be happening now? I fried a motor?

Click to expand...

Disconnect the phase wires from the controller and make sure the ends aren't touching each other. Spin the wheel. If it's still difficult to turn, then you have a short in the phase wires or windings causing plug braking. If you short the ends of the phase wires alternately and also all 3 together, you can figure out which one(s) are the problem. If you're lucky it's outside of the motor, otherwise it's inside or often where the wires enter.

If the motor seems to spin freely while disconnected from the controller, short 2 of the phase wires together and turn it to feel the resistance of what a short is like, typically a notched kind of cogging like a second hand on a clock ticking off each second. Then plug them back to the controller. If the turning resistance returns then you have a short in the controller, probably in one bank of the mosfets. You can connect them alternately to figure out which is the problem.

Does your scooter have the security feature of the wheel being hard to turn when off? Maybe that is malfunctioning and causing your issue.

With all these electrical problems you're having, I'd examine all of the wiring, even the lights. Maybe it's the 12V system for the lights or something like that, which has been the source of all of your issues. I know on the factory controllers that I got with some scooter motors, the ebrake cutoff for the controller was activated by the 12V brake lights. I can easily see a short there causing the throttles to burn out, since they're 5V.

You need to learn how to use your ebike tester. Lyen here on the forum sells some, so check and see if it's the same and that could be a way to get instructions. Personally, I would remove the motor and open it up. If the windings look fine and tested fine above, then while open I would take the opportunity to change the bearings for some better quality Japanese bearings. I'd also change out the phase wires for the thickest wire I could fit. Then I would change all of the wiring on the entire scooter and be done with the problems. It's a lot cheaper than a new scooter and a lot cheaper than your time. Over there, even if the motor windings are burnt and shorted, you should be able to find a motor factory and get it rewound very cheaply, or pick up a an even better motor for quite cheap.

BTW, to answer your previous question, yes network cable would work, but it's solid core wires and flexing them back and forth breaks them easily. Any wire multi-strand wire will work, and if you want color coding, just put a piece of colored tape at each end.

thanks that is very useful info. Turns out that the controller is fried ( the smell is really strong) and theres slight damage to the motor as well, I do not know whats wrong with the motor. Indeed I do have the security lock for the motor. Its been removed too. I just bought the on and off switches for the signal, headlights and horn. the wires are so close together. Its not hard to short them.

Hi

I changed the switches for the lights and horns and noticed that theres a slight burnt part on the horn switch. It have been running smooth these while. I notice that the motor has been smoother after the servicing from the shop.

Perhaps the motor was faulty but ridable when I first bought it. I have been asking him what is the problem but I cannot understand what he meant.