Mdubz

Hey guys, just looking for a quick, easy way to determine my battery wire's polarity. Don't tell me to buy a voltmeter or something, I just want a quick easy way to determine my polarity. (Anything with light bulbs, a spare motor, etc?) Thanks.

pbmax

Hrmmm....... but wouldn't a voltmeter be oh so handy? I use mine just about every day.

Mdubz

Nah, this is probably going to be a one time thing, and I'm quite lazy. Theres gotta be an easy way to determine polarity...

pbmax

LED + resistor will do it - it'll light up in one direction only. Pick a pretty low-ohm resistor and make sure you know the polarity of the LED.

Mdubz

I'll try that, but where exactly do I get a resister? :P Can I pry it from some old toy, or can I just connect it to the LED? I'll try and figure something out.

hands without shadows

The red wire is positive, the black wire is negative. You should really get a multimeter, its very usefull.

Mdubz

Not always. I had bought a custom made battery from someone a while back, and the wires were set up with wrong colors. This current battery is also a custom battery, so I want to make sure polarities are correct before I start soldering.

pbmax

You're on your own for a resistor...most RC toys will have one or more, but it'll be tough to use if it's a surface mount type. If you use an LED w/o a resistor you risk cooking the LED.

Get a multimeter! $5 from harbor freight: [link=http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90899]http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90899[/link]

I've used that same piece of junk for years and it works great (cept I got it back when it was yellow and $10).

guver

My Feedback: (325)

Check it the same way as you checked the other one. lol.

plug it into a motor and see if it spins the correct way or the same way as a known battery.

ps lots of batteries are marked also.

Mdubz

Lmao, the last way I checked my battery fried my esc. I was able to test out this one by sticking the wire up a small LED flashlight. Got deans on all my connectors now, w00t! (It's almost addicting soldering deans onto your stuff. :P)

pbmax

Haha, I love soldering It usually means that new RC toys have showed up via usps, or the Brown santa (soldered up a new quark today!).

Mdubz

Yeah, this next week is going to be killer, waiting for my Wraith 7K/Quark 33 to arrive. Along with a bunch of other stuff that I ordered months ago and hasn't showed up yet... lol

pbmax

Nice [8D] I'm waiting for the rain to stop so I can go romp on my buddy's vtx mst1 with my 3s brushless mini inferno