Promblems with BMS rear rack battery

ldc

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Jun 2, 2020
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vfr400

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If you didn't get the integrated controller, there's a compartment at the front for housing a controller. When you open it, you,'ll see what you have to do - usually solder two wires to the back of the connector. Whatever you do, don't get them the wrong way round. Always check with a meter.

Those batteries often have a small rocker switch at the back somewhere.
 

ldc

Pedelecer
Jun 2, 2020
58
4
If you didn't get the integrated controller, there's a compartment at the front for housing a controller. When you open it, you,'ll see what you have to do - usually solder two wires to the back of the connector. Whatever you do, don't get them the wrong way round. Always check with a meter.

Those batteries often have a small rocker switch at the back somewhere.
Thanks I do not see the switch anywhere though
 

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Nealh

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Have you connected up a controller yet ?
 

vfr400

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Try press and hold the switch for a few secs - or even as long as 10 secs. Maybe it has sleep mode.

IIRC, that switch works the light in the back as well somehow. I think it has mult-functions. It's possible that the battery terminals at the front are permanently live. Did you test them?
 

Nealh

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ldc

Pedelecer
Jun 2, 2020
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Try press and hold the switch for a few secs - or even as long as 10 secs. Maybe it has sleep mode.

IIRC, that switch works the light in the back as well somehow. I think it has multi-functions. It's possible that the battery terminals at the front are permanently live. Did you test them?
no, i don't have a meter and will not be buying one or a soldering iron either but thanks for your helpful feedback. I held the button down for 30 seconds as I initial thought it had a sleep mode.
 

ldc

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Jun 2, 2020
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If you read the post, correctly it says I had no idea where/how to connect the controller to the battery. So of course I haven't connected the controller The battery came with no instructions, as i also posted, so no point being sarcastic about it and to be honest if I knew I'd have to solder anything I would not have bought it, who spends all that money to then have to solder and potentially ruin an expensive piece of kit, surely the battery should still switch on, without having to solder anything.
 

vfr400

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no, i don't have a meter and will not be buying one or a soldering iron either but thanks for your helpful feedback. I held the button down for 30 seconds as I initial thought it had a sleep mode.
You shouldn't be messing with ebike stuff if you don't have a meter. It's absolutely essential equipment. You can do a lot of damage without one.
 

vfr400

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If you read the post, correctly it says I had no idea where/how to connect the controller to the battery. So of course I haven't connected the controller The battery came with no instructions, as i also posted, so no point being sarcastic about it and to be honest if I knew I'd have to solder anything I would not have bought it, who spends all that money to then have to solder and potentially ruin an expensive piece of kit, surely the battery should still switch on, without having to solder anything.
Maybe you should explain what you bought.
 

ldc

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Jun 2, 2020
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Maybe you should explain what you bought.
I was referring to the 2 sarcastic people above.

I purchased

a 500w front wheel 26"
an s12s controller
torque arm
PAS sensor
48v 17ah rear battery with pannier rack
an LCD3 Display
all from bmsbattery

The site in question, nor any other site I have visited has mentioned needing a multimeter or soldering iron, when purchasing an e-bike kit I would have just got an e-bike to begin with, instead of converting my old bike.

Just looking at woosh bikes website, which another member kindly recommended I look at their bikes, I've just looked through their manual on e-bike kits and no mention of needing a soldering iron or multimeter, so why you say you should not get an e-bike kit without a multimeter, I don't understand, yes maybe after some usage I'd need one, particularly if I have a problem, like I said if the site said i need one, especially a soldering iron, i simply would of not got one
 

vfr400

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I was referring to the 2 sarcastic people above.

I purchased

a 500w front wheel 26"
an s12s controller
torque arm
PAS sensor
48v 17ah rear battery with pannier rack
an LCD3 Display
all from bmsbattery

The site in question, nor any other site I have visited has mentioned needing a multimeter or soldering iron, when purchasing an e-bike kit I would have just got an e-bike to begin with, instead of converting my old bike.

Just looking at woosh bikes website, which another member kindly recommended I look at their bikes, I've just looked through their manual on e-bike kits and no mention of needing a soldering iron or multimeter, so why you say you should not get an e-bike kit without a multimeter, I don't understand, yes maybe after some usage I'd need one, particularly if I have a problem, like I said if the site said i need one, especially a soldering iron, i simply would of not got one
These sites are selling components for hobbyists. If you don't know about the stuff and how it goes together, you should be buying a ready-made plug and play kit from Woosh, YSPower, Dillenger or somewhere like that, whose kits have instructions and backup.

Your controller is not going to fit in the battery compartment because it's miles too big. You'll have to get a toolbag that goes under the saddle and stick it in there, then you'll have to run some 13g silicon wires to it from the back of the battery connector in that empty controller compartment. That means soldering to the terminals plus soldering connectors to the wires, which you'll have to get from somewhere. I'd recommend XT60s. You might also have to extend the PAS cable too.

Finally, you have to be very careful when fitting a 500w motor to the front forks. don't just bolt it up and expect it to work. getting it wrong can result in a serious accident (no bullsh¦t) so make sure you show photos and take advice from the forum when doing it.

Which exact motor did you get?
 
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Nealh

Esteemed Pedelecer
Aug 7, 2014
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These sites are selling components for hobbyists. If you don't know about the stuff and how it goes together, you should be buying a ready-made plug and play kit from Woosh, YSPower, Dillenger or somewhere like that, whose kits have instructions and backup.

Your controller is not going to fit in the battery compartment because it's miles too big. You'll have to get a toolbag that goes under the saddle and stick it in there, then you'll have to run some 13g silicon wires to it from the back of the battery connector in that empty controller compartment. That means soldering to the terminals plus soldering connectors to the wires, which you'll have to get from somewhere. I'd recommend XT60s. You might also have to extend the PAS cable too.

Finally, you have to be very careful when fitting a 500w motor to the front forks. don't just bolt it up and expect it to work. getting it wrong can result in a serious accident (no bullsh¦t) so make sure you show photos and take advice from the forum when doing it.

Which exact motor did you get?
The guy hasn't got a Scooby vfr he's got no chance of getting the kit working, he's in way over his head.
 

ldc

Pedelecer
Jun 2, 2020
58
4
The guy hasn't got a Scooby vfr he's got no chance of getting the kit working, he's in way over his head.
It was you who recommended I bought the kit for one. Look its simple if the site had mentioned any of this I simply wouldn't of bought it. Even still the kit didn't come with any instructions what so ever. It isn't rocket science, though and it was simple to work out how to connect everything to the controller, everything except the battery However, for a start I don't have a soldering iron and I'm not prepared to go soldering something so expensive, if you've nothing construction to say then just move on, I was looking for a reason why the battery wouldn't switch on not, a condescending one, of a self styled so called guru, at that. You have an awful lot to say on almost every post I come across, suggesting you have way too much time on your hands. Look how useful the above person has been, without been condescending
 

ldc

Pedelecer
Jun 2, 2020
58
4
These sites are selling components for hobbyists. If you don't know about the stuff and how it goes together, you should be buying a ready-made plug and play kit from Woosh, YSPower, Dillenger or somewhere like that, whose kits have instructions and backup.

Your controller is not going to fit in the battery compartment because it's miles too big. You'll have to get a toolbag that goes under the saddle and stick it in there, then you'll have to run some 13g silicon wires to it from the back of the battery connector in that empty controller compartment. That means soldering to the terminals plus soldering connectors to the wires, which you'll have to get from somewhere. I'd recommend XT60s. You might also have to extend the PAS cable too.

Finally, you have to be very careful when fitting a 500w motor to the front forks. don't just bolt it up and expect it to work. getting it wrong can result in a serious accident (no bullsh¦t) so make sure you show photos and take advice from the forum when doing it.

Which exact motor did you get?
Thank you have been very helpful, as you can imagine I had no idea, I'd need to solder anything as its not mentioned on the site in question nor did it have any instructions. It didnt even have the screws to connect the battery to the rack.

I got bafang bmp front hub 500w https://bmsbattery.com/ebike/584-16216-bafang-bpm2-48v500w-front-driving-e-bike-motor-wheel-ebike-kit.html#/213-rpm-201. The length of pas wire was sufficiently long and I got the measurements for the controller before it came and got a bike bag to fit it. I got 2 extra thick torque arms as it was going on the front wheel. I was going to use p clips to fit them but my local DIY ship didn't have any. Either way vfr, the battery should switch on so you can check it works. Before soldering. I appreciate your help, thank you
 

vfr400

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Jun 12, 2011
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The battery might be switching on. How would you know it is or isn't. We always check that with a meter, which is essential equipment even if you buy a plug-and-play kit.

These are the things you're going to need to complete the installation:

Digital multimeter
60w soldering iron
40/60 tin lead solder (not the free stuff you get in soldering kits)
Assortment of heatshrink tube.

The 500w BPM motor has immense torque, so it's axle can easily twist itself out of the forks. Correct installation is critical. You'll probably have to file your dropouts to get it in. I always file the drop-outs deeper as well to re-centralise the axle. I think that at 30amps, even with double torque arms, theres a strong possibility that it'll pop your drop-outs. I would only fit one with that much current in steel forks.

Which forks do you have.