Whatt's up meter and UM battery

[rickswa]

hello.

I am just getting into the switch from wall wart to Thunder AC6 charger and from all the reading it seems a watt meter will be a good investment as well. I was considering the Whatt's up meter but here's my question. My SC batteries have deans connectors that I put on. I have a HZ champ that has the 1S UM battery. If I put deans on the meter leads, do they make (or could I make) a conversion cable that would let me go from the deans connectors to the UM connections for the tiny batteries on the champ? Thanks for any info.

Rick

[flydiver]

Yes you can make a conversion. Don't know if there is a commercial one. The little part for the micro is a pain to find.
In this sport soldering is a pretty important skill to have.

[rickswa]

ok. Thanks. And dumb newbie question #1,485. If I can't hunt down that piece, is there a fairly cheap meter you know of that would work for the small lipos?

As a side note, I didn't have enough time to get thru the charge/discharge of my Nimh batts so I went for it and charged the thunder power 1s lipo yesterday on the thunder AC6. I wont lie, I was a bit nervous just from reading things but put it on my concrete basement floor, did all the settings, charged at 2C (approx) and it actually went much easier than I thought. No fire, no shock, no boom...just a charged battery. I have to say that with how easy it was, it is making me wonder about this whole conditioning charge, periodic discharge/charge, etc with the Nimh. I hate to put a brand new battery aside but maybe I'll use it a few times first then just do the lipo thing. I know....you told me so. LOL. I was just amazed at how fairly simple the whole lipo process was. just make positive I have the settings right, monitor the battery and off it goes. great charger so far.

[flydiver]

There is a lotta discussion about forming charge. I think it's a more useful tool for batteries that are going to be used for low amp draw like receivers. For power batteries personally I'd just charge them about C/5 and use them. Try not to hammer them with high charges and discharges for a few cycles. This is also true for lipo.
For your old batteries it's likely of no use at all. They are probably shot anyway. Tender loving care will not revive a dying battery no matter what kind it is. Batteries do not live forever and neglect is one of the worst offenses. The higher the performance, the worse they seem to be with neglect has been my experience. Also true for lipo.

Like I said, lipo is actually easier than NiMh. But if you screw up the consequences are higher. That's the rub.

I think you can harvest the tip off one of these:
mCPx Parallel Charge Cable
epbuddy.com/index.php?main_page=product_info&cPath=26_14&products_id=265

There will be no wattmeter with a commercial end for a battery of that type. You'll want to make an adapter. Once you mess around with it awhile I think you'll find it's not worth the hassle.
You'll also need a secondary receiver battery to power it. Over something like 4v the battery being used powers the wattmeter. Under that you need an axillary battery.

Found this while browsing for the adapter. I think you'll like it.
mCPX Battery Charging (Part 1)
www.youtube.com/watch?v=iTpFOnaM5u4

[rickswa]

thanks again for the info. Sounds like I'll just stick with the meter for bigger batteries. Do you use one for yours at all? My only concern was charging multiple 1S lipos with the hyperion adapter and getting them all to the same voltage for charging. From what I gather, for example, if I have a 160mah and a 150 mah 1s lipo I could charge at a total 2C of .6A. But they would have to be exactly the same voltage when starting the charge. is that correct thinking?

[flydiver]

Sorry, don't do parallel charging (got several chargers) so I'm not up on the details of the method. There are a bunch of threads in RCGroups and Wattflyer on it. Some of the mico threads may deal specifically with charging a bunch of those little batteries.

I don't think they have to be EXACTLY the same....that's what balance charging is about, putting them back to the proper balance. In a PACK each cell is charged individually when series charging. That's important. What you are doing is merely charging a bunch of individual cells. Conceptually not any different.
Having them WAY out of size and capacity makes the charger work extra duty to bring them back to proper status. It has to CHARGE the LOW cells and DISCHARGE the higher cellls. These chargers CHARGE OK but their DISCHARGE function is pretty lame so they get slowed WAY down. This is more of a problem on large capacity batteries since they need to move a lot of juice around and just don't have the electric 'muscle'. For your dinky cells it won't be much of a problem.

My wattmeter does 90% duty as a motor testing and only a bit as battery checker. Your charger itself has some screen feedback about charge status. If think if the charge harness is set up right you can charge 6 cells and look at the status of each cell while you charge it.

Hyperion Board? I take it you have this?
www.maxamps.com/pdf/Hyperion%20Micro%20Parallel%20Adapter%20Instructions.pdf
So that's parallel charging.


I'd start here with a cup of coffee:
www.rcgroups.com/forums/showthread.php?t=1357720

and here if you want to learn a lot:
EP Buddy Safe ParaBoard Coming Soon – Charge multiple batteries at the same time
www.rcgroups.com/forums/showthread.php?t=1302613

Note - as I understand it you will NOT be able to see the individual cells on your charger as it is treating them as one single larger cell.
This is where my understanding breaks down so validate this for yourself. My description above is based on series charging. That's what 3S means, a 3 SERIES lipo cell (not parallel). My chargers are too small to readily charge multiple packs so I just have several chargers and don't worry about it. Except for my micro heli I have little interest in micros so haven't gone down your path.

[ginginho]

As Fly says, they don't need to be of the same exact voltage, but wildly different can cause problems. When two packs are connected together (necessary for parallel charging) the one with a higher voltage will dump to the one with lower in very quick fashion until they are at the same. Where there is a big differential, this can be a significant current that may overload the connection (some wires or a PCB) to an extent that it fails.
If you are only doing this with small 1S packs it's probably not too much of a concern, it can become pretty significant where large capacity, multiple S packs are concerned.

[rickswa]

thank you again for the great info. Yeah this would just be for the 1s packs but it wont be too hard to get them to about the same voltage. I was just worried they had to be the EXACT voltage or something like that. thanks again.