Ebike Shuts Down Under Load or High RPMs Without Load

[Ryan Saldanha]

EBike Specs:
I have custom built a mid drive ebike with a frame mounted motor and controller (components linked at bottom). I built a 48V 13S battery pack with 3 cells in parallel. A 48V BMS is installed on the battery. The battery is connected to the controller with an XT60 connector. All the battery components including the compatible 48V charger were purchased from VRUZEND.com. I installed a twist throttle that came with the motor and controller.

Issue:
When I ride the bike and open the throttle, the motor drives the rear wheel, accelerating the bike, but as soon as the bike reaches a few MPH all power is lost and the system shuts down. The motor stops and the throttle display fades to black, suggesting that the battery as fully stopped supplying current. If I very lightly feather the throttle, I can sustain the power nearly indefinitely, but if the throttle opens too much, only a fraction of its full range, the bike loses power. When I raise the back wheel of the bike off the ground and open the throttle, the back wheel reaches very high RPMs and can be sustained indefinitely with almost a fully opened throttle, but the bike does shut down in a few seconds if the throttle is fully opened. In the both the test with load and without load, I can use the system again by disconnecting and reconnecting the connector between the battery and controller.

Current Theories and Questions:
Because the power is lost at a certain level of throttle use, it seems the issue could be related to amp draw, suggesting that the BMS may be shutting down the battery when too many amps are being drawn. The BMS is rated for 30A continuous draw while the controller is rated for 33A continuous draw. I have heard that this should not be a major issue, because the BMS should be able to temporarily handle 33A and all 33A are not being drawn continuously for general use. Is this reasonable? What are the most effective methods of measuring amp draw from the battery? Could I install a resistor between the connectors and then measure the voltage drop over the resistor? Will a general multimeter be able to measure between the positive terminal and positive lead of the battery measure the draw?
I have measured the voltage of the battery as the motor is running with the wheel off the ground and the power is lost with the voltage dropping from around 47V to 45-46V which I do not believe is enough for the BMS to shut down the battery, correct?
What are the other variables that may cause this issue? Is there a possibility of the electrical components in the controller having issues? Is it possible that the connectors are not the right gauge to support the current coming from the battery? I would appreciate any thoughts on this issue.

Components:
Motor/Controller/Throttle- https://www.amazon.com/Electric-Brushless-Complete-Controller-Motorcycle/dp/B07G2LZHD8/ref=sr_1_4?keywords=kunray+ray+ebike+motor&qid=1567786124&s=gateway&sr=8-4

Battery Cells- https://vruzend.com/product/set-of-two-2-samsung-inr18650-30q-3000-mah-18650-battery-cells/

BMS- https://vruzend.com/product/48v-13s-battery-management-system-bms/

Charger- https://vruzend.com/product/48v-lithium-ion-battery-charger-3-amps/

Connector: https://vruzend.com/product/xt60-connectors-with-14awg-silicone-wire-leads/

 

[Rocko]

I think it's unlikely you are exceeding 30A. In addition to the BMS and Controller, the problem could be a poor connection anywhere between the battery build connections to the controller.

Here are some steps to follow for troubleshooting. Depending on the results, you may find the problem or the results of the testing will help figure out the next steps.

1) Double check all connections starting at the taps on the pack for anything not making good contact. Gonna assume that's all good now.

2) Determine if there is an overload -- Measure the current flow out of the battery. Before the BMS. See the max amps drawn while running full speed. The easiest way to do this is with a DC clamp meter. Here is an example (be careful if you buy one, the less expensive ones only do AC current):

https://www.amazon.com/Meterk-Multimeter-Auto-ranging-Capacitance-Non-contact/dp/B0721MKXBC

If you aren't seeing anywhere near the 30A limit when it stops, something is breaking down under load. If you are seeing near 30A, stop here and post again.

3) Measure the voltage at the outputs from the BMS under load. If that voltage isn't dropping out, the BMS and the pack are probably OK. The controller is suspect. Stop and post the results.

4) If there is a substantial voltage drop at the BMS output, this clears the controller for now.

5) Now check the voltage at the inputs to the BMS. If the input to the BMS is also dropping, the problem is the pack. Go to step 7). If the input isn't dropping, it's likely the BMS.

6) If the BMS is suspected, temporarily bypass the BMS and feed the controller directly from the battery to see if that resolves the problem. If so, stop and post results.

7) The BMS input voltage is dropping out under load, so the battery pack is suspected. Check the voltage at the battery pack taps. If dropping here, it's the battery pack/build. If not dropping, here the battery pack is probably OK and there is faulty wiring between the BMS and the Pack.

8) Stop and post results.

Thank you finally someone no,s I have the same problem but mine happens after crossind wires and get mine to work I have to fether it little at time get it to run

 

[Rocko]

I am going to try it now I need help so bad this is my only transportation

 

[Rocko]

Yes number 6 was my next try but I was scared to do that because I destroyed Batt like that before but ok I doing as soon as iron gets hot

 

[Rocko]

I think it's unlikely you are exceeding 30A. In addition to the BMS and Controller, the problem could be a poor connection anywhere between the battery build connections to the controller.

Here are some steps to follow for troubleshooting. Depending on the results, you may find the problem or the results of the testing will help figure out the next steps.

1) Double check all connections starting at the taps on the pack for anything not making good contact. Gonna assume that's all good now.

2) Determine if there is an overload -- Measure the current flow out of the battery. Before the BMS. See the max amps drawn while running full speed. The easiest way to do this is with a DC clamp meter. Here is an example (be careful if you buy one, the less expensive ones only do AC current):

https://www.amazon.com/Meterk-Multimeter-Auto-ranging-Capacitance-Non-contact/dp/B0721MKXBC

If you aren't seeing anywhere near the 30A limit when it stops, something is breaking down under load. If you are seeing near 30A, stop here and post again.

3) Measure the voltage at the outputs from the BMS under load. If that voltage isn't dropping out, the BMS and the pack are probably OK. The controller is suspect. Stop and post the results.

4) If there is a substantial voltage drop at the BMS output, this clears the controller for now.

5) Now check the voltage at the inputs to the BMS. If the input to the BMS is also dropping, the problem is the pack. Go to step 7). If the input isn't dropping, it's likely the BMS.

6) If the BMS is suspected, temporarily bypass the BMS and feed the controller directly from the battery to see if that resolves the problem. If so, stop and post results.

7) The BMS input voltage is dropping out under load, so the battery pack is suspected. Check the voltage at the battery pack taps. If dropping here, it's the battery pack/build. If not dropping, here the battery pack is probably OK and there is faulty wiring between the BMS and the Pack.

8) Stop and post results.

ok i going out side try it if it works i can connect hi end boost converter to replace bms
right
?

 

[Rocko]

A just had a good idea, as battery pack is new, never used, 36V, 12Ah, 41.7 volt charged, I'll try ride bike and measure battery pack voltage.
If it drops a good bit, it's battery pack.

ya i have meter i bot that doe,s just that i gonna hook it up to

 

[Rocko]

I think it's unlikely you are exceeding 30A. In addition to the BMS and Controller, the problem could be a poor connection anywhere between the battery build connections to the controller.

Here are some steps to follow for troubleshooting. Depending on the results, you may find the problem or the results of the testing will help figure out the next steps.

1) Double check all connections starting at the taps on the pack for anything not making good contact. Gonna assume that's all good now.

2) Determine if there is an overload -- Measure the current flow out of the battery. Before the BMS. See the max amps drawn while running full speed. The easiest way to do this is with a DC clamp meter. Here is an example (be careful if you buy one, the less expensive ones only do AC current):

https://www.amazon.com/Meterk-Multimeter-Auto-ranging-Capacitance-Non-contact/dp/B0721MKXBC

If you aren't seeing anywhere near the 30A limit when it stops, something is breaking down under load. If you are seeing near 30A, stop here and post again.

3) Measure the voltage at the outputs from the BMS under load. If that voltage isn't dropping out, the BMS and the pack are probably OK. The controller is suspect. Stop and post the results.

4) If there is a substantial voltage drop at the BMS output, this clears the controller for now.

5) Now check the voltage at the inputs to the BMS. If the input to the BMS is also dropping, the problem is the pack. Go to step 7). If the input isn't dropping, it's likely the BMS.

6) If the BMS is suspected, temporarily bypass the BMS and feed the controller directly from the battery to see if that resolves the problem. If so, stop and post results.

7) The BMS input voltage is dropping out under load, so the battery pack is suspected. Check the voltage at the battery pack taps. If dropping here, it's the battery pack/build. If not dropping, here the battery pack is probably OK and there is faulty wiring between the BMS and the Pack.

8) Stop and post results.

nope it still cuts off after disconecting bms

 

[Rocko]

nope it still cuts off after disconecting bms

i found broke brake lever cable so i disconnected it now i have redue every thing reatach brake cable

 

[Rocko]

EBike Specs:
I have custom built a mid drive ebike with a frame mounted motor and controller (components linked at bottom). I built a 48V 13S battery pack with 3 cells in parallel. A 48V BMS is installed on the battery. The battery is connected to the controller with an XT60 connector. All the battery components including the compatible 48V charger were purchased from VRUZEND.com. I installed a twist throttle that came with the motor and controller.

Issue:
When I ride the bike and open the throttle, the motor drives the rear wheel, accelerating the bike, but as soon as the bike reaches a few MPH all power is lost and the system shuts down. The motor stops and the throttle display fades to black, suggesting that the battery as fully stopped supplying current. If I very lightly feather the throttle, I can sustain the power nearly indefinitely, but if the throttle opens too much, only a fraction of its full range, the bike loses power. When I raise the back wheel of the bike off the ground and open the throttle, the back wheel reaches very high RPMs and can be sustained indefinitely with almost a fully opened throttle, but the bike does shut down in a few seconds if the throttle is fully opened. In the both the test with load and without load, I can use the system again by disconnecting and reconnecting the connector between the battery and controller.

Current Theories and Questions:
Because the power is lost at a certain level of throttle use, it seems the issue could be related to amp draw, suggesting that the BMS may be shutting down the battery when too many amps are being drawn. The BMS is rated for 30A continuous draw while the controller is rated for 33A continuous draw. I have heard that this should not be a major issue, because the BMS should be able to temporarily handle 33A and all 33A are not being drawn continuously for general use. Is this reasonable? What are the most effective methods of measuring amp draw from the battery? Could I install a resistor between the connectors and then measure the voltage drop over the resistor? Will a general multimeter be able to measure between the positive terminal and positive lead of the battery measure the draw?
I have measured the voltage of the battery as the motor is running with the wheel off the ground and the power is lost with the voltage dropping from around 47V to 45-46V which I do not believe is enough for the BMS to shut down the battery, correct?
What are the other variables that may cause this issue? Is there a possibility of the electrical components in the controller having issues? Is it possible that the connectors are not the right gauge to support the current coming from the battery? I would appreciate any thoughts on this issue.

Components:
Motor/Controller/Throttle- https://www.amazon.com/Electric-Bru...y+ebike+motor&qid=1567786124&s=gateway&sr=8-4

Battery Cells- Set of two (2) Samsung INR18650-30Q 3000 mAh 18650 battery cells – VRUZEND DIY Battery Kit

BMS- 48V 13s Battery Management System (BMS) – VRUZEND DIY Battery Kit

Charger- 48V Lithium-ion battery charger (3 Amps) – VRUZEND DIY Battery Kit

Connector: XT60 connectors with 14AWG silicone wire leads – VRUZEND DIY Battery Kit

well i just got hit by car so i am dine for awile

 

[E-HP]

well i just got hit by car so i am dine for awile

That’s truly unfortunate. I hope you have a speedy recovery.

Once you are back to troubleshooting, I offer this advice:
This forum is interactive. The quality of advice you receive is directly tied to the quality of information you provide. Generally, these details are obtained in a series of questions that require you to provide the necessary details or responses.

You started two threads on your issue. In both cases you received prompt responses, asking for additional information, which you ignored/abandoned. Instead you began responding to random old threads, appearing to have conversations with folks that haven’t been on the forum for years, as well as with yourself. While this is one way to avoid interaction or provide information, it won’t bring you any closer to solving the issue.

I suggest that when you are ready, choose one of your existing threads and respond to questions and provide the requested details in order to resolve the issue. Alternatively, if you want to avoid interaction all together, you can do a lot of searching and reading, since most issues have been brought up at one time or another. No need to even post.

shorted? plus and minus

i connected plus minus wrong and now it turns off with me on it but works fine suspended in air with no rider i130lb. my specs are:48v13S 15amp 1000watt 3led ear 1000watt 48vdc hub motor kit non circle connections r,y blade and soderless bring conections on a yellow 3 for motor 2 for power...

endless-sphere.com

48v 1000watt 13s ebike shuts off

Ya I shorted my bike one night and now it still work fine with no rider at full speed but with me on it it turns off when I try go full throttle every thing else seems OK I tested control for mosfet short you no power and motor wires its OK I taken it apart for visal inspection looks good...

endless-sphere.com

 

[Rocko]

well i just got hit by car so i am dine for awile

No its works fine if I am not on it

 

[Faisal]

EBike Specs:
I have custom built a mid drive ebike with a frame mounted motor and controller (components linked at bottom). I built a 48V 13S battery pack with 3 cells in parallel. A 48V BMS is installed on the battery. The battery is connected to the controller with an XT60 connector. All the battery components including the compatible 48V charger were purchased from VRUZEND.com. I installed a twist throttle that came with the motor and controller.

Issue:
When I ride the bike and open the throttle, the motor drives the rear wheel, accelerating the bike, but as soon as the bike reaches a few MPH all power is lost and the system shuts down. The motor stops and the throttle display fades to black, suggesting that the battery as fully stopped supplying current. If I very lightly feather the throttle, I can sustain the power nearly indefinitely, but if the throttle opens too much, only a fraction of its full range, the bike loses power. When I raise the back wheel of the bike off the ground and open the throttle, the back wheel reaches very high RPMs and can be sustained indefinitely with almost a fully opened throttle, but the bike does shut down in a few seconds if the throttle is fully opened. In the both the test with load and without load, I can use the system again by disconnecting and reconnecting the connector between the battery and controller.

Current Theories and Questions:
Because the power is lost at a certain level of throttle use, it seems the issue could be related to amp draw, suggesting that the BMS may be shutting down the battery when too many amps are being drawn. The BMS is rated for 30A continuous draw while the controller is rated for 33A continuous draw. I have heard that this should not be a major issue, because the BMS should be able to temporarily handle 33A and all 33A are not being drawn continuously for general use. Is this reasonable? What are the most effective methods of measuring amp draw from the battery? Could I install a resistor between the connectors and then measure the voltage drop over the resistor? Will a general multimeter be able to measure between the positive terminal and positive lead of the battery measure the draw?
I have measured the voltage of the battery as the motor is running with the wheel off the ground and the power is lost with the voltage dropping from around 47V to 45-46V which I do not believe is enough for the BMS to shut down the battery, correct?
What are the other variables that may cause this issue? Is there a possibility of the electrical components in the controller having issues? Is it possible that the connectors are not the right gauge to support the current coming from the battery? I would appreciate any thoughts on this issue.

Components:
Motor/Controller/Throttle- https://www.amazon.com/Electric-Bru...y+ebike+motor&qid=1567786124&s=gateway&sr=8-4

Battery Cells- Set of two (2) Samsung INR18650-30Q 3000 mAh 18650 battery cells – VRUZEND DIY Battery Kit

BMS- 48V 13s Battery Management System (BMS) – VRUZEND DIY Battery Kit

Charger- 48V Lithium-ion battery charger (3 Amps) – VRUZEND DIY Battery Kit

Connector: XT60 connectors with 14AWG silicone wire leads – VRUZEND DIY Battery Kit

My bike conversion kits doing this and should I leave it on charge for 2-3 days r u sure this is safe