yetti831

I have a cheap lipo charger that came with an RTF package. The 12v AC adapter I had was only charging at 350ma, and the output on the charger is .75amps, so I was charging below the 750ma the charger was capable of. I found an old laptop adapter that says the following:


Input: 100-240V~1.5A
Output:19V 3.16A


So, is 3.16A not 3160ma ?

I am correct in thinking that this laptop adapter is putting out 3160ma into a charger than can only put out 750ma? If so, will the charger only put out the 750ma and operate safely, or will it damage the charger and battery? It seems to be working fine, as I just topped off a battery very quickly with no problems.


My charger reads an Input of 15-18 V

Thanks

CGRetired

My Feedback: (1)

That's fairly confusing. Remember that the safest way to charge LiPo's is outside.

First of all, 1 ma is one mili-ampere or .001 ampere. So, if it charges at 35 ma then that's .035 amps. 750 ma is .75 amps. 350ma is .350 amps.

How do you know what rate it was charging at? Does it display the charging current (amperes)?

If the capacity is x number of amps, or miliamps, whatever you choose as your scale of measurement, then you will charge that pack over time at a particular charge rate (amps or milamps per hour). Just keep in mind that no matter what, an ampere is 1.00 amps and or 1000 miliamps depending on how you scale it. 1 amp = 1000 miliamps and conversely, .001 ampere (a) = 1 miliamp (ma).

Also think of charging the battery, or filling the tank in reference to amps per hour or miliamps per hour, whatever.

I would be very careful using chargers that were not designed for charging the battery you are using. If you charge them to quickly, you will have a fire on your hands.

Stick to what is recommended for that battery and, no matter what you do, do it outside.

CGr

If you take a battery that needs 1000 miliamps to full charge (thinking it is fully drained) which is 1 ampere, and you have a charger capable of 100 miliamps per hour or .100 amperes, then it will take a little over 10 hours to fully charge that battery, no matter what kind of battery it is.

MinnFlyer

My Feedback: (4)

Watch this video, then YOU decide how to charge it

http://www.youtube.com/watch?v=-DcpA...eature=related

Stuntpilot51

Minn,
I think he's using the laptop power supply to power his charger. After reading the post three times I don't think he's charging with 3.16 amps directly into the lipo. If he is, he's going to be in trouble.[X(][X(]

With that being said, I would probably not use the laptop PS to power the charger as it's above the chargers rated input voltage of 15-18 volts.

yetti831

Thanks for all of your replies. I ended up not using that power source.

I recently purchased this Turnigy Charger: [link=http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=7028&Product_Name=Turnigy_Accucel-6_50W_5A_Balancer/Charger]Charger[/link]

However, as you can guess, I've been trying to find an appropriate power source. I'm at my computer for 90% of the day, so I like to charge my batteries right by me.

I found a regulated power source on ebay, and I was wondering if the Turnigy comes with the appropriate cables to hook up to this.

[link=http://cgi.ebay.com/Samlex-RPS1204-Regulated-DC-Power-Supply-New-in-Box_W0QQitemZ270321164365QQcmdZViewItemQQptZLH_Def aultDomain_0?hash=item270321164365&_trksid=p3286.c0.m14&_trkparms=72%3A1205|66%3A2|65%3A12|39%3A1|240%3A13 18|301%3A1|293%3A1|294%3A50]Regulated Power Source[/link]

Thanks again.

Stick 40

I have a 12 volt charger for my li-po's and I have a 12 volt batter I use in the basement and I then charge it with a auto charger. This may not help you, its just the way I do it.

You can get a converter for 110v ac to 12v dc.

whstlngdeath

My Feedback: (15)

Regardless of the amperage output of the A/C adapter you use, the A/C adapter is not doing any of the charging. It is only supplying the charger with what it needs to operate. If the A/C adapter you use only puts out 350mah, and the charger needs 5 amps to operate, then the adapter is not enough to power the charger. The output of the charger alone, both in voltage and amperage, is what goes into the battery, not what comes out of the A/C adapter. If the charger is rated for only 750mah output, then it will charge a 750mah rated lipo battery in one hour. That would be charging the battery at a 1C rating. I would not recommend charging lipos any higher than 1 times the rated capacity of the pack.

Jesse

yetti831

Okay, so the charger I'm getting is CAPABLE of 5amps and is rated at 50watts. The power supply I just bought has an output of 13.38 (13.8v*4amps=55watts) and has a rating of 4 continuous amps, and 6 at surge. However, I have1100 mah and 2200 mah batteries, so I would only be charging at 1.1 amps and 2.2. amps, respectively. If my power supply is putting out 4 continuous amps, and I am only using 1.1amps to charge my 1100 mah battery, what happens to the surplus energy being put out by the power supply?

The Ghost

Why not just get the power supply from the same place as the charger [link=http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=6879&Product_Name=16A_14v_DC_Power_Supply_for_Chargers]HERE[/link] or you could get [link=http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=6256&Product_Name=12V_5A_Power_Supply]THIS[/link] one instead. The Charger that you got is a great beginner charger that will last quite a few years. I still have and still use my one even if it is only to balance the batteries now.

Cheers

yetti831

To tell you the truth, I didn't browse the site for adapters. For some reason I'm so use to everything coming with it's own adapter, so I totally forgot I'd needed one. I did, however, see the adapter in your second link after I made the purchase, but I didn't like the switchable between 110/240. I imagined getting it and having to take it apart to drop the voltage from 240. As for the adapter in your first link, while it looks like it's a great product and is probably twice as good as the power source I got, it's also twice as expensive, and I've been spending too much recently! I also ordered from the USA warehouse, so I wouldn't have been able to combine the power supply with the other items in my order. But, thanks for the links. I'll probably buy that power source soon!

whstlngdeath

My Feedback: (15)

Any surplus energy is dissipated as heat. Because the power supply is capable of putting out 4 amps, it doesn't mean that the charger will draw 4 amps. The power supply will give the charger only what it needs, (voltage and amperage), to charge the specific battery at the rate you set. There is a lot more going on in the charging process than this simple explanation, but to make it easier to understand and to make sure you have enough power supply, the charger's specs are what you need to look at, and whatever voltage and amperage it needs from the power supply to operate normally, is how you choose a big enough power supply.

Jesse

The Ghost

I have been using the 16A charger with my chargers and have had 4 chargers running of it at the same time to charge 3cell 2200mah packs. Just something to think about later. With the switching it is just a switch at the input side of the charger that you flip to change the input voltage setting.

Cheers

yetti831

Thanks for your reply.

So, if I'm charging a 2200mah lipo, and I set it to 2.2 amps, it will only draw 2.2amps from the power source. Makes sense.

Another quick question. My power source says that it can put out 6 amps of surge. How long can this "surge" be maintained?

Thanks a lot!

whstlngdeath

My Feedback: (15)

That's completely up to the quality of the power source. Heat is the enemy here, so just like speed controls and batteries, heat buildup will be the limiting factor.

Jesse

yetti831

Yeah, that source looks great if you have multiple chargers.

And, as far as the lesser power source goes , I was hoping it was that simple, but I didn't see anything on the photo, and I didn't want to order it only to be disappointed upon arrival.

Thanks for the input.

Stuntpilot51

Yetti,
The power supply you bought will work just fine. Also remember to charge in a fireproof container, I use an old crock pot!

jg95762

My Feedback: (2)

Even though the power supply will put out 4Amps I don't think it will push the full 4A out unless the charger is drawing that much. To charge a 2200mah lipo I doubt that it needs the full 4amps.