I bought 2 Thunder Power TP-205 Balancer Adapter. From maxamps.com. How do I hook them up? Or do I, since I have the Astro Flight 109 charger. I bought this charger becuase I thougt it would be the best for 18.5 volts. Most of the other chargers in that price range would not charge that big of a pack.

http://64.233.167.104/search?q=cache:RlLVofDPihIJ:http://www.espritmodel.com/documents...balancer&hl=en

I don't know what
means..

PCM guard is not a balancer. It only cuts the charge if any cell reaches 4.25v (or something like that). Since it won't balance the pack, there can still be overdischarge if the LVC is set.

The Thunder Power balancer adapter should come already wired to the pack. This would allow the use of the TP-205 balancer.
The Astro Flight charger is good for the price (9 cells and 8amps). But, it isn't a CC/CV charger, it is a pulse charger. Most balancers assume that you will be using a CC/CV charger, as the is the standard charge method. They will get confused with the pulsing of the AF109 and could kick in at the wrong time (and potentially make the charge take longer).

So what do u sugest. Also do I need to by a cut off warning? Where do they have them that will work well with my set up

You need a undervoltage cut off, to keep your lipo's in good condition.

Good thing you bought that TP balancer. !

@metalman, you say, that the TP should come already wired to the packs. It is used for charging only, and it has got a plug that connects it to the pack, so i don't really know what you mean with that?

He was talking about his Maxamps battery pack that came with a plug on it that would plug into a TP-205 balancer. He doesn't have the balancer, but the plug he has will work with it. The plug should come already soldered onto the individual cells in the pack. This TP plug can be used for anything since it only acts as an access point to the individual cells.

As far as a LVC device goes, you could try this one:
http://66.241.195.91/lithium/lithium.asp?path1=lithium
There are others out there, but this is the only one that I have bookmarked. :)

You know what this does? is it an immediate cuttoff to the motor or what does it do? it is auto sensing this one right? nice device..

It will pulse the motor (noticably) when the voltage is almost to 3v, and will cut it at 3v (or somewhere very close). It says that it autodetects the number of cells.

Sounds like a winner to me...

It would be nice if you where only able to drive slowly if it dropped bellow the 3.1 volts or so.. It would cut the high current absorbing character from the motor as well.. that would be a nice feature for cars imo.

Once the voltage of the pack climbs back up after it hits LVC, then you could drive the car back slowly. You might hit LVC again, though.