Battery Power Supply Help Colored Wires

[Erlon]

I have a 12ah 48v battery. The plug is a computer type three prong cord. If' I use an old computer cord, how do I hook it up to the positive (red) and negative (black) wires coming from the battery controller box? The leads coming out of the three prong computer cord are black, white and green. Thanks.

 

[trex]

yes but you should check the voltage with a DVM first.

 

[Deleted member 4366]

You use the outer two pins. You have to get them the right way round. You can trust that the red and black on the controller are positive and negative, but do not trust the colours on any battery or charger. Always test them with a meter to determine which is which. You have been warned!

 

[Erlon]

My multimeter seems to be broken (it turns on but does not seem to register anything). Do you happen to know which of the leads I should use? Thank you.

 

[trex]

post a picture of your meter, we'll help you.

 

[Erlon]

My neighbor just fried the black wire by plugging it into his ac socket.

 

[trex]

there is a PP9 battery inside the case. It may need replacing.

 

[Deleted member 4366]

My neighbor just fried the black wire by plugging it into his ac socket.

Plenty on Ebay

http://pages.ebay.com/link/?nav=item.view&id=201305594612&alt=web

 

[Erlon]

I went to the bike shop and had it tested. Black is negative, white is positive, according to the owner.

I have another problem now. It works fine when I lift the back tire and give it the throttle, but as soon as I try to ride it, it gives a half second burst of power then it dies along with the display.

 

[Deleted member 4366]

Knackered battery.

 

[Erlon]

The battery was bought new from China. Is it possible it's not putting out the amps required by the controller under load? Could the BMS be engaging? Possible to remove the BMS?

 

[Deleted member 4366]

Charge it up, then measure the voltage on the terminals with a voltmeter. If you don't have a voltmeter that works, you need to get one.

What motor and controller do you have? What type of battery is it?

 

[Erlon]

The controller and motor came together in a kit, brand new. I read on another forum that this controller requires 40A. My battery only puts out 30A? I will order another multimeter.

Motor: SYM-48-100f (1000watt, rear hub)
Controller:SYK-48-100w

Battery: EMC4812001
Nominal voltage: 48V

Weight: about 4.9kg

Standard Charge (0-45 ℃): Use 2A constant current charge to 42V ,and use constant voltage charge to the current less than 100mA

Standard discharge: 2A constant current discharge to 27.5V
Fast discharge: 5A constant current discharge to 27.5V

Nominal capacity: 12Ah (standard discharge)

Cycle life: Standard charge and fast discharge cycle 500 times , the capacity will notless than 60% of the nominal capacity .

Maximum continuous charging current: 5A

Maximum continuous discharge current: 15A

Maximum instantaneous working current: 30A

Resistance (23 ± 2 ℃): ≤ 250mΩ

Battery case: Whitebait Aluminum Case

Protection system: Internal BMS

Charger: 54.6V / 2A

Size: 385 * 110 * 75mm

Storage conditions: -15 ~ +35 ℃, relative humidity: 45-75%, atmospheric pressure: 86-106KPa

Use the operating temperature:

Discharge: 0-60 ℃; Charging: 0-45 ℃

 

[Deleted member 4366]

It's probable that your BMS is tripping if it's a 40A controller. You could try reducing the the current by crimping or filing the shung in the controller. 30 amps at 48v should be mord than enough.

If you're not sure how to do that, remove the screws in the sidd of the controller and the one in the end-plate at the wires end. Pull out the contents and take a photo of the region around where the black battery wire is soldered.

 

[Erlon]

Here it is. If I cut one in half will it give me 26.6A?

 

[Deleted member 4366]

If you cut one, you'll get 2/3 of the current. You can add solder to the other two to bring it back up if you need to.

 

[Erlon]

Thank you. I will try that.

 

[Erlon]

The bike is rideable now but still shuts off if I give it too much power. As long as I take it easy on the throttle it is fine. Thanks for your help!

 

[Bobbo1260]

You use the outer two pins. You have to get them the right way round. You can trust that the red and black on the controller are positive and negative, but do not trust the colours on any battery or charger. Always test them with a meter to determine which is which. You have been warned!

I have a similar question. sorry if I’ve posted this in the wrong place but incan’t find anything on dc converters in the search option.
i have identified the positive and negative in the controller that comes from the battery however the controller is a yosepower solid state unit where all the wires are set in a grey resin.
I could peel back the insulation on the outer pins in the controller to solder on a positive and negative to supply dc 12 controller but I’m concerned as to whether when soldering the wires would this cause a bad connection on the existing soldered wires and is the heat of the soldering iron going to damaged the nearby resin.

thanks in advance.

Bobbo

 

[saneagle]

I have a similar question. sorry if I’ve posted this in the wrong place but incan’t find anything on dc converters in the search option.
i have identified the positive and negative in the controller that comes from the battery however the controller is a yosepower solid state unit where all the wires are set in a grey resin.
I could peel back the insulation on the outer pins in the controller to solder on a positive and negative to supply dc 12 controller but I’m concerned as to whether when soldering the wires would this cause a bad connection on the existing soldered wires and is the heat of the soldering iron going to damaged the nearby resin.

thanks in advance.

Bobbo

Taking a step back, what do you mean by a 12v controller and what do you want to do with it?