battery or controller fault?

[my.motion]

Using multimeter the voltage on my new 48v is reading 49v, however when i connect the controller and check the voltage on the battery/controller connector it is only reporting 1.5v? what could be wrong? The thumb throttle light is consanly off. No power is flowing through the controller although the battery is contantly reading 49 volts

 

[Straylight]

If the 1.5v reading is before the power actualy goes through the controler, then it is an all but complete break in the cable from the battery. I'd try a continuity test of the cable, then check it for damage, lastly opening/rewiring the connectors.

 

[aaannndddyyy]

Using multimeter the voltage on my new 48v is reading 49v, however when i connect the controller and check the voltage on the battery/controller connector it is only reporting 1.5v? what could be wrong? The thumb throttle light is consanly off. No power is flowing through the controller although the battery is contantly reading 49 volts

Hi, which battery have you got, which make of controller, if its a 48volt lipo battery it should read around 58-60volts hot off the charger.
1.5v off the controller dosent make a lot of sence, can you post a pic of which wires your testing.

 

[my.motion]

I have a 48v lithium ion battery. When I switch on and off the battery several times the thumb controller light come one and says half full and when I turn the trottle everything shutsdown, no power at all. It is the controller that comes with 1000w motor same guy you (aaannnddddyyy)bought it from. How do i do a continuity test please

 

[my.motion]

image measuring at the connection

 

[Straylight]

On your multimeter, there should be a musical note symbol and/or a line with an arrow on it, switch the selector to this. You'll find that if you touch the probes together, the meter will beep. This is telling you that current is flowing between the probes, so to test a cable for electrical continuity simply touch the probes to both ends of each core in turn. If there is a connection, the meter will beep. Another thing you can check for with this is a short circuit within the cable, by touching the probes to different cores at the same end.

NB: make sure both ends of the cable are disconnected first

 

[aaannndddyyy]

Can you get access the back sides of both battery and charger connectors? If you can do this then plug both battery and charger connector together and use a meter to check continuity with your test leads on the back sides of each connector. You should be able to identify which pins are not connecting and need repair/replacement.
Also if you can get the power light to light then put your meter across the battery to read the 49v again then see if the voltage drops when you open the throttle, if it drops below around 42v the bms is cutting the power.

 

[Straylight]

imageView attachment 875 measuring at the connection

Forgive me if I'm wrong, but it looks like you're measuring the voltage on the same colour wire, this would give you the reading of near 0v, measure it between the red and the black as this is what you've effectively done at the battery.

 

[my.motion]

Forgive me if I'm wrong, but it looks like you're measuring the voltage on the same colour wire, this would give you the reading of near 0v, measure it between the red and the black as this is what you've effectively done at the battery.

sorry the image is misleading, I am actually using the red as live as you are suggesting, the image should show two arrow line at each point that says 'multimeter here' I get the reading 49v at this points but goes to zero after throttle is applied. When I unplug the power connect to controller and measure the voltage the battery is reading 49v, does bms shutdown the power on then off or should the reading from battery stay at shut off? why is the thumb throttle light not come on straight away? I have to switch on and off the battery several times before the thumbthrottle light comes on

 

[my.motion]

Also if you can get the power light to light then put your meter across the battery to read the 49v again then see if the voltage drops when you open the throttle, if it drops below around 42v the bms is cutting the power.

At the battery connector the reading sstarts at 49v
As soon as I connect the controller to the battery connector the power shuts down to 1.8-1.6v, sound like bms is not allowing power through. I connected a 36v sla battery and can see the thumb throttler power light up. If the BMS is faulty what options are available to fix this? Why is bms shutting this down? Yes the voltae across the battery drops to 1.8v when throttle activated

 

[my.motion]

More picture added

 

[Mussels]

At the battery connector the reading sstarts at 49v
As soon as I connect the controller to the battery connector the power shuts down to 1.8-1.6v, sound like bms is not allowing power through. I connected a 36v sla battery and can see the thumb throttler power light up. If the BMS is faulty what options are available to fix this? Why is bms shutting this down? Yes the voltae across the battery drops to 1.8v when throttle activated

Looks like a faulty battery unfortunately, the BMI may be working correctly and shutting the power off because the battery can't hold a charge. You have used a spare battery to show the controller isn't at fault.

 

[my.motion]

Looks like a faulty battery unfortunately, the BMI may be working correctly and shutting the power off because the battery can't hold a charge. You have used a spare battery to show the controller isn't at fault.

The battery is holding charge because it is still reading 49v even after shut down it goes back to 49v

 

[flash]

I had a similar fault with my fathers bike. I had similar readings to yours and was convinced it was the battery or the BMS, the bike was still under guarantee so we returned it to the distributor he fitted another battery but it was still the same. He then exchanged the bike for a new one. At a later date I was speaking the distrubutor on another matter and asked him if he ever found the fault and he said they changed the controller and the bike worked OK.
I never saw the old bike again but I have no reason to doubt him.

 

[my.motion]

asked him if he ever found the fault and he said they changed the controller and the bike worked OK.
I never saw the old bike again but I have no reason to doubt him.

I have a controller on my milan2 and 36v battery just wondering whether to test using these. what would be the best combination for testing please?

 

[Mussels]

The battery is holding charge because it is still reading 49v even after shut down it goes back to 49v

Attempt at a non techie answer...
If the battery is knackered it can show a high voltage on an open circuit but as soon as anything tries to draw current it dies as there's nothing to back it up. For a good battery to drop voltage that much it would have to be almost a short circuit, if that was happening on a 48 volt battery things would get hot very quickly. The BMI may sense a short circuit and shut it down, disconnect the battery and measure the resistance across the controller input with the throttle on and off. There may be a reason this test is not good for controllers but hopefully someone will tell us.

 

[my.motion]

thanks, how do i measure resistance across the controller please?

 

[my.motion]

The BMI may sense a short circuit and shut it down, disconnect the battery and measure the resistance across the controller input with the throttle on and off. There may be a reason this test is not good for controllers but hopefully someone will tell us.

there is no difference when throttle on or off, I can still see values (then goes to 0:00) on the multimeter when I do continuity and resistance (ohm) test between the controller 'power' cables, measured this when battery was disconnected, please see attach image