Battery Wiring N00b Query

General Discussion about electric bicycles.
docrocket   100 mW

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Battery Wiring N00b Query

Post by docrocket » Jul 23 2018 4:55pm

I am repurposing my 36v battery from my old bike into a new bike, and I have a couple of (undoubtedly rookie) questions about wiring.

The battery has three outbound connectors (see photo). One (black connector) is the power out, one (white) is the charging connector, and the smallest one (I am assuming) is for reading the voltage.

I have a charging port which has two main wires. My question is, does it matter which wire goes to which in the charging connector on the battery?

https://ibb.co/jAcSpT
https://ibb.co/bHsA9T

Much obliged for help!

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Rassy   10 MW

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Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:12pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

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Rassy   10 MW

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Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:12pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

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Rassy   10 MW

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Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:13pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

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Rassy   10 MW

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Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:14pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

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Rassy   10 MW

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Location: Eugene, Oregon USA

Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:14pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

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Rassy   10 MW

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Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:15pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

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Rassy   10 MW

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Location: Eugene, Oregon USA

Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:15pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

User avatar
Rassy   10 MW

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Location: Eugene, Oregon USA

Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:15pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

User avatar
Rassy   10 MW

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Posts: 2059
Joined: Apr 08 2007 10:58am
Location: Eugene, Oregon USA

Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:15pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

User avatar
Rassy   10 MW

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Posts: 2059
Joined: Apr 08 2007 10:58am
Location: Eugene, Oregon USA

Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:15pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

User avatar
Rassy   10 MW

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Posts: 2059
Joined: Apr 08 2007 10:58am
Location: Eugene, Oregon USA

Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:15pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

User avatar
Rassy   10 MW

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Posts: 2059
Joined: Apr 08 2007 10:58am
Location: Eugene, Oregon USA

Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:15pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

User avatar
Rassy   10 MW

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Posts: 2059
Joined: Apr 08 2007 10:58am
Location: Eugene, Oregon USA

Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:15pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

User avatar
Rassy   10 MW

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Posts: 2059
Joined: Apr 08 2007 10:58am
Location: Eugene, Oregon USA

Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:16pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

User avatar
Rassy   10 MW

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Posts: 2059
Joined: Apr 08 2007 10:58am
Location: Eugene, Oregon USA

Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:16pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

User avatar
Rassy   10 MW

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Posts: 2059
Joined: Apr 08 2007 10:58am
Location: Eugene, Oregon USA

Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:16pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

User avatar
Rassy   10 MW

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Posts: 2059
Joined: Apr 08 2007 10:58am
Location: Eugene, Oregon USA

Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:16pm

Yes, it does matter which wire on the charger goes to which wire on the battery. Your question is vague. Didn't you have to connect your battery to your charger on the old bike? Where is the picture of your charger? Doesn't your charger still have the matching connector on it?

At any rate, the positive (red) wire on the battery needs to be connected to the positive output wire on the charger (also red?). And the negative (black) wire on the battery needs to be connected to the negative output wire on the charger.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

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Rassy   10 MW

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Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 5:19pm

Hey mods, there was no response from ES, but when it did respond there were over a dozen entries made. My bad, can you fix?
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

docrocket   100 mW

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Re: Battery Wiring N00b Query

Post by docrocket » Jul 23 2018 8:23pm

Rassy, the charger is a standard 3-prong round connector. The battery used to be attached to a charging port built into the bike,but that port is gone. I have a replacement port off a different battery with the same connection style. It has a black wire and a blue wire.

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Rassy   10 MW

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Re: Battery Wiring N00b Query

Post by Rassy » Jul 23 2018 9:42pm

Sorry about messing up your thread. Use your volt meter to make sure the (+) wire from the battery goes to the (+) wire of the charger. Just plug in the charger without hooking it up to the battery to check which wire is (+), and hence which is (-). If you don't have a multi-meter or haven't used one report back for guidance, but you don't want to guess at the polarity.
-Rassy-

Two Delta Trikes equipped with a Bafang BBS02
viewtopic.php?f=28&t=88536&p=1291260#p1291260

docrocket   100 mW

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Re: Battery Wiring N00b Query

Post by docrocket » Jul 23 2018 9:51pm

I have a voltmeter. I know how to use it to check the voltage (one pin on each connector of my battery and it shows 40.6 volts) but guidance on how to tell which line is positive would be helpful.

Having done that (however it's done) , I think I get it: find the positive wire on the charger and make sure that the accompanying slot on the port goes to the positive wire on the battery.
Last edited by docrocket on Jul 23 2018 9:52pm, edited 1 time in total.

docrocket   100 mW

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Re: Battery Wiring N00b Query

Post by docrocket » Jul 23 2018 9:51pm

And no need to apologize, you're helping me out!!

Jon NCal   1 kW

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Re: Battery Wiring N00b Query

Post by Jon NCal » Jul 23 2018 10:09pm

docrocket wrote:
Jul 23 2018 9:51pm
I have a voltmeter. I know how to use it to check the voltage (one pin on each connector of my battery and it shows 40.6 volts) but guidance on how to tell which line is positive would be helpful.

Having done that (however it's done) , I think I get it: find the positive wire on the charger and make sure that the accompanying slot on the port goes to the positive wire on the battery.
If the red probe from the meter is on positive and black probe on negative, the voltage will read as a positive number. If the reading is a negative number then you got it backwards.

docrocket   100 mW

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Re: Battery Wiring N00b Query

Post by docrocket » Jul 23 2018 10:10pm

Ok, that makes sense. Thanks everybody!

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