i am new wont turn on without charger attached

[postalpaul1]

hi i bought a 1000 watt kit on ebay for 350 it is 48 volts did not come with instructions but all conectors were hooked up in box i have a problem if i turn it off at switch it wont come on unless i hook up the charger the battery is lithium ion from juiced riders so if i go somewere like work i cant turn it off (but) if i pull the fuse out while it is on it sparks and then works but i dont want to mess up the contacts in the fuse holder please help

 

[Affliction]

Sounds like you have a bad bms or other problem that's tripping the protect circuit. Plugging in the charger usually trips the bms back on.
You must have this thing hardwired to the bike if the only switch you have is the fuze.
It's a good idea to have a master power switch that is easilly acessible, that way you can reset the bms on the fly.
If you draw too much current from your pack the bms will protect it, that's what it's for. Just reset and don't try to accelerate too hard.

 

[Juiced Riders]

Hi, there could be 2 situations were this could happen:
The first is that the battery is not very well connected to the controller. If there is any sort of spark or arc,
the BMS will shut down the battery as it is bad to draw big currents from LiFePO4 Cells. It is not exactly
clear how it is connected, but it appears that the controller's on/off switch briefly draws a big current and
causes the BMS to trip. You can try to install a inline switch and keep the controller's on/off switch in the "on"
position. This will be the same as removing and replacing the fuse (and safer).

The second situation is that the battery's BMS is damaged. If this is the case, we will replace your battery immediately
or offer full refund. However, if you are able to ride the bike even after the issue and only encounter
this problem when the controller is switched on, the BMS may not be damaged and replacement will not improve this issue.

Hope this helps,
-Tora

 

[postalpaul1]

I HAVE THE BATTERY THEN A FUSE THEN A SWITCH THEN THE WIRES GO INTO THE CONTROLER THEY MUST ALWAYS BE ON I HAVE HAD THIS HAPPEN SINCE DAY ONE BUT THIS IS FIRST EBIKE AND HAVE KNOW IDEA THERE IS NO LOOSE CONNECTIONSI SODERED IN THE SWITCH AND CRIMPED TO BATTERY IT WORKS GREAT WHEN ON BUT I HAVE TO HAVE CHARGER PLUGED IN TO TURN IT ON I HAVE BEEN TAKING CHARGER WITH ME WHILE AT WORK I WOULD HATE TO LEAVE IT ON ALL DAY I DONT KNOW WHAT THAT WOULD DO TO MY BATTERY (DEAD) I WANT TO GET HOME

 

[Affliction]

He's probably inadvertantly wiggleing the fuze back in thus giving the controller some precharge voltage so it doesn't trip the bms.
I agree that if it rides fine while on then it's probably not the bms. Sounds like a controller issue.

 

[dogman dan]

I'm certainly no electronics whiz, but it doesn't sound like the usual loose connection issue or bms tripping issue to me. Something in the on off cirucuit of the controller. A good DC switch at the battery may be a good solution, and leave the controller turned on.

Beats me why the charger would affect it, charger higher voltage than the battery? Controller on off circuit needs higher voltage than the battery to work?

Not normal for sure, I'd try for a new controller from the vendor if he's not a jerk. But ebay bargain vendors,,,,, might be cheaper to just buy a new controller from a more local vendor than ship and old one back and ship a new one in from china.

 

[Juiced Riders]

Hi,
The way I understand the situation, it appears that the controller may be tripping the BMS when it is turned on. This leads me to believe that the controller's switch circuit acts almost like a short for a split second until it's fully powered up. It is likely designed for SLA battery packs as they don't have BMS protection and can power through this startup period. Keeping in the charger plugged in while turning the controller on, is in a way preventing the BMS from shutting down the system as it is technically charging.

This can happen even if your connections are solid. Since the system works fine once it's on, the battery and BMS is functioning normally and not defective. We will be happy to refund or replace the battery, but a replacement battery will almost certainly produce the same result and will be a waste of shipping costs.

I can only suggest that you install a inline switch between the battery and the controller. This should work as you stated that removing and reinserting the inline fuse will allow you to power on the system without the charger. If you want we can send you a battery bag with a key-switch free of charge and hopefully this improves the situation. In the meantime, I suggest that you can leave the controller powered on as it generally does not draw much current when in an idle state.

If you can make a picture of or give model number of the controller, we will make a note of this unusual interaction between your controller and this battery pack.

 

[HighTekBikes]

You might want to try the method that has been described on here (do a search on here) to "pre-charge" the caps in the controller by first connecting a resistor between the pack and the controller. This prevents the spark. In your case it might also prevent the BMS from shutting down. The charger is probably just preventing the shutdown from the current spike. There is a way to wire up a switch so the resistor gets connected first, then the main connection is made.

 

[Juiced Riders]

I am glad the battery bag with the key-switch fixed the issue. So strange how these things work sometimes.

 

[Chalo]

The way I understand the situation, it appears that the controller may be tripping the BMS when it is turned on. This leads me to believe that the controller's switch circuit acts almost like a short for a split second until it's fully powered up.

I wonder if the controller's capacitors are sucking up their initial charge fast enough to trip the BMS's current limit.

Chalo

 

[dnmun]

i agree with chalo, the charging of the input caps is triggering the BMS to shut down. but that guy lost any sympathy from me when he went to the ALL CAPS JERK mode.