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jatekman
03-14-2007, 08:03 PM
My new Magpie arrived yesterday with the brushless set-up recommended by Brian of Mountain Models (BM2408-21 motor, Thunderbird BL 18 and PolyRC 20C 1500 mAh 3S1P 11.1V). A few newbie questions after looking it over rather quickly:

Why does the Li-Po battery have two sets of wires? Is one for charging and the other for discharging? It has two black and red rather thick wires with no connector and 4 wires (3 black, 1 red) with a funky connector on the end (not a Deans or JST). I assumed the two thick wires connected to the matching-color ones on the ESC, but now I'm not sure as they have different thicknesses?

Also, concerning the ESC, do I have the following set-up right?:

The connector resembling a servo connections goes to the receiver.
The black, white, and red wires on one end connect to the motor (solder them to the same color 3-wires from the motor, or solder a connector? If a connector, what type, Deans won't work?)
The other two black and red wires on the other end connect to..? The plane came with a set of Dean's, I assume for one of the battery connections & the two-wire part of the ESC?

I have read many threads on here concerning soldering and electronics but until I actually had something in my hand it was hard to visualize...
any help anyone can provide is appreciated and if there are any links anyone knows about explaining how a typical BL motor, battery and ESC are connected would help, also.

Grasshopper
03-14-2007, 08:10 PM
Hi jatekman,

We'll see if we can help here. The fat red and black wires on your lipo are what will hook to the ESC. You will need to solder the FEMALE Deans connector to the battery and the male Deans connector to the ESC. The two wire side of the ESC is what connects to the battery. There should be a + and - on the deans connector. If not, when you look at it, the two posts make a "T" the top of the T is the +. Only solder one lead of the battery at a time then heat shrink it so you don't accidentally touch the two battery wires together. NOT GOOD!

The 3 wire side of your ESC goes to the motor. It doesn't matter which wire goes to which. I use bullet connectors soldered with heat shrink on the motor leads. When you're ready to turn it on, check the motor rotation. If it's going the wrong way, switch any two wires.

The small plug with 4 wires on your battery is for charging.

The small servo like connector on your ESC goes to the throttle port on your receiver. Make sure the black wire is on the negative side of the receiver.

Hope that helps, if not ask away.

jatekman
03-15-2007, 01:02 AM
Grasshopper (Tom):

Thanks for the quick response to my question; it really helped. I also went to the LHS and they were fairly helpful, too.

And just an FYI: I printed off your step by step build thread for the Magpie AP and plan on using it as a reference as I attempt to correctly assemble the kit. I'm excited about getting started, it's just a matter of finding the time to do it. And I'm pretty clueless when it comes to the electronics part of these planes, but I've been reading and trying to learn as much as I can. I plan on trying quite a few practice solders before I actually work on the expensive parts I bought w/ the kit. I'm learning that there is a lot more to this hobby than first meets the eye! (but I think that is a good thing).

Thanks again,
John

smokejohnson
03-15-2007, 01:45 AM
Watts up jatekman welcome to wattflyer. Here is a link with some good info on soldering. I do ok and it is definetly getting easier for me but I have a hard time soldering. I don't know if it's cause now I am getting frustrated because I don't get the same results everytime or if it is my cheap equipment. I rigged up a block of wood with clothes pins to hold my connectors/wires while soldering. It sucks. I'll find the link for the helping hands, you may know what it is but I had never seen one before.

Do you have a thread going on your Magpie build? If not be sure to post it here or link to it, I would like to know how it works out. The Magpie is on my list for my next plane.

smokejohnson
03-15-2007, 01:53 AM
http://www.wattflyer.com/forums/showthread.php?t=17140

http://www.mpja.com/solder_equipment.asp

Solid Hit
03-15-2007, 01:57 AM
The 4 wires on the battery are for a BALANCE charger or for just balancing the pack. You can use the same two wires (red and black) for charging as well as connecting to the esc.

Grasshopper
03-15-2007, 05:02 AM
The 4 wires on the battery are for a BALANCE charger or for just balancing the pack. You can use the same two wires (red and black) for charging as well as connecting to the esc.

Good point Bill. I always forget that because I balance charge all my batteries every time.

Airhead
03-15-2007, 05:15 AM
Good point Bill. I always forget that because I balance charge all my batteries every time.
Evenin' Tom,
what do you mean.."balance charge"?
Thanks...

Grasshopper
03-15-2007, 05:26 AM
Evenin' to you too Bruce,

A balance charger individually charges each cell to the same voltage. I don't know a lot of detail about the technical aspects of it, but it's my understanding that when the pack has completed charging, every cell is at the same voltage. Without a balance charger, it is possible for the cells to finish at different voltages (out of balance). I use all Common Sense RC Balance chargers so they always balance the packs when they charge. Hope that's clear. If not, maybe some others with more detail on how they work will chime in.

jatekman
03-15-2007, 05:50 AM
Hello,

I took a picture of the connection on the Lipo pack I referred to earlier in this thread...can anyone tell what type it is and/or where I could obtain its match? It probably doesn't really matter because I don't think the charger I have (Triton 2) balances battery packs. It is advertised as a charger, discharger, and cycler, although it seems like I saw something about an accessory or add-on that could be used w/ the Triton 2 to maybe balance the packs? I'll have to look into it.

So it is okay to charge the lipo with the other connector (Deans ultra)? Will it reduce the life of the battery by not balancing it?

Thanks,
John

jatekman
03-15-2007, 06:05 AM
Hey Smokejohnson-

Thanks for providing the soldering help links, I appreciate it. I was planning to rig something similar to what you described but after your input, maybe I'll invest in a soldering station, or at least a third hand. If I'm going to be serious about this I might as well try to obtain any advantage I can. As of the moment I don't plan on doing a step by step build thread on the Magpie-there's already a couple I've found on here and it would take a lot more time. Speaking of, I need to go start on the wing.

smokejohnson
03-15-2007, 12:21 PM
Here is a link for the helping hands I was talking about. http://www.allerc.com/product_info.php?cPath=1&products_id=1434

On the balance plug and charger I can let you in on what I have learned. The Triton series does not have balancing capabilities built in. You need a seperate balancer. First I tried the Equinox and a lipo with Hyperion taps. Had to order an adapter and it never did work for me.:mad: Others use the Equinox with other than Electrifly packs and make it work. Others say the Equinox will only work with Electrifly packs. I say who cares to make it work at all. I don't like the set up having to count flashes and double click the button. So I now use my Triton with a PCM-Pro balancer on a lipo pack from Electric Power. Works great for me.:) For me balance taps are confusing.:confused: You can make your own adapters and there are those that say this is a non issue but I try to avoid soldering at all cost.;):)

http://2dogrc.com/ecommerce/os/catalog/pcmpro-2s3s4s-balancer-p-1993.html

Solid Hit
03-15-2007, 01:11 PM
Jatekman, I use a Poly Four charger and charge through my Deans. Every so often I hook up a balancer to regulate my pack. I've never had a problem that way ..... oh, wait a moment, see: http://www.wattflyer.com/forums/showthread.php?t=17256

That was human error by setting the charger to the wrong setting and had nothing to do with balancing or not balancing your pack.

Mr.Clean
03-15-2007, 02:23 PM
I just bought my first lipos and charger. I was sitting here in my office with a car battery plugged into my charger plugged into my lipo through my deans connector and I started reading this thread. I read the second post, the one by Grasshopper, and suddenly had heart failure. :eek:

I assumed that I was charging the pack incorrectly and that I was about to cause one of those catastrofic (spelling) lipo failures. I immediatly jumped up and unplugged everything. I cursed and tantrumed because I knew that I just fried a brand new lipo and possibly the charger and car battery. :(

I grabbed a cup of coffee sat down and continued to read this thread.
Now I feel so much better knowing that I can charge through the deans.

Here is a couple of questions.
1) Now that there is a 15 min charge on one lipo can I put it back on the charger and finish it off or do I run it dead and start over again?

2) I also bought the Common Sense balancer. The LHS guy said to plug it in every four ou five charges to make sure everything is working properly but that I don't always have to charge/balance.

3) I use the Enegizer rechargables in my radios. Once I cycle them through a charge how long can I let them stay dormant before I need to recharge them. Do they bleed off like the NiM-AH batteries do?

4) Are any of you guys familure with the Ripmax lipo chargers?

Thank you
Clean

Grasshopper
03-15-2007, 05:58 PM
I just bought my first lipos and charger. I was sitting here in my office with a car battery plugged into my charger plugged into my lipo through my deans connector and I started reading this thread. I read the second post, the one by Grasshopper, and suddenly had heart failure. :eek:

I assumed that I was charging the pack incorrectly and that I was about to cause one of those catastrofic (spelling) lipo failures. I immediatly jumped up and unplugged everything. I cursed and tantrumed because I knew that I just fried a brand new lipo and possibly the charger and car battery. :(

I grabbed a cup of coffee sat down and continued to read this thread.
Now I feel so much better knowing that I can charge through the deans.

Here is a couple of questions.
1) Now that there is a 15 min charge on one lipo can I put it back on the charger and finish it off or do I run it dead and start over again?

2) I also bought the Common Sense balancer. The LHS guy said to plug it in every four ou five charges to make sure everything is working properly but that I don't always have to charge/balance.

3) I use the Enegizer rechargables in my radios. Once I cycle them through a charge how long can I let them stay dormant before I need to recharge them. Do they bleed off like the NiM-AH batteries do?

4) Are any of you guys familure with the Ripmax lipo chargers?

Thank you
Clean

Sorry about that Mr. Clean. Sure didn't mean to scare you. As I said, I always forget about charging through the main leads since I never do it. Hope you got to sit back down and enjoy your coffee.

1) You should be able to finish charging your lipo. You never want to run one dead. You should always have a low voltage cut off in place and preferably not even hit that voltage if possible. Going below the recommended voltage for your pack can ruin it.

2) Is this an extra balancing device you hook to your charger? I'm not familiar with it. My Common Sense Chargers automatically balance as they charge.

3) I use Energizer rechareables in a lot of my camera equipment. For some reason, mine seem to lose their charge if they sit for very long not being used. I just always make sure they are charged up before I use them.

4) Not familiar with Ripmax chargers

Sorry again for scaring you.

MountainFlyer
03-15-2007, 07:20 PM
I have some LiPo's that are so old they don't even have balancing taps on them .. and there still quite good. I use them all the time .. and charge them through the main leads... since thats all they have.. :)