Warning: While the chargers we are discussing are some of the safest you can get, there is still some associated risk and danger with any of these setups. Please make sure you understand the technology and risks before buying and using it. Also, make sure you are charging your batteries in a safe manner!
If you fly large electric models in the 4s and higher range you will soon find yourself longing for a higher power charger. Here's the results of the research and reading I've done that lead me to the decision I made on what my "big battery charger" is. The executive summary is:
You need a 1000 watt power supply that can deliver 24 VDC and you should pick either the FMA charger (PowerLab 6 or PowerLab 8) or the iCharger (306B or 3010B). You won't find any bigger chargers because anything over 1000 watts will require more AC amperage than you likely have available.
Watts = Volts x Amps
- Battery chargers are rated in WATTS and run on DC power.
- To provide DC power to your charger, you'll also need a power supply or a deep cycle battery
- To get to the 1000 watt range, you'll need a 24 VDC power supply (or battery) and charger.
- You're fancy new charger can run on a 12 VDC power source, but it will only deliver 400-600 WATTS of output power, depending on charger
- You'll not likely charge a single pack at 1000 watts - you'd rather charge many similar packs at the same time with a parallel charging board or parallel cables
- The popular parallel charging boards/cables allow up to 6 packs to be charged at the same time.
- To parallel charge packs you'll need to use "electrically similar packs" (same cell count, similar capacity, and similar charge level)
- These chargers are capable of discharging packs which comes in handy for testing capacity/health of batteries
- You can plug these high power chargers into your computer to show lots of statistics during charging/discharging
This is the first concept that you will absolutely need to understand to figure out what all of this charger stuff means and to determine how much power you need for your charging workstation. Below are a few notes on this formula.
- Power Supplies - Most 24 VDC 1000 Watt power supplies are 42 Amp output. 24V x 42A = ~1000 Watts. If you have a 12 VDC power supply that outputs 42 Amps, you would have a 500 Watt (12V x 42A) power supply.
- Assume you want to charge a 4-Cell (4S) LiPo at 10 Amps. A 4S LiPo is 16.8 Volts (4.2 V * 4 cells). The wattage to charge this would be 168 Watts (16.8 volts * 10 amps).
More Power Supply Details
- To take this a step further into parallel charging, if you wanted to charge 2 of the 4S packs in the previous example (20 Amps total charge), you would be charging at 336 Watts (16.8 volts * 20 amps).
- You'll need to make sure that your power supply can deliver the needed AMPERAGE to get to 1000 WATTS output on your charger. Chargers can only use 85-90% of the power that is sent from the power supply. Therefore, if you want to OUTPUT 1000 watts from your charger, you're going to need ~1175 (1000 / 0.85) watts of output from your power supply
- There are "smart" power supplies that can provide DC power more efficiently than "dumb" power supplies.
- "Smart" power supplies have "PFC" (Power Factor Correction) - "dumb" power supplies do not.
- PFC power supplies can deliver their rated capacity using less AMP on the AC side than non-PFC.
- To actually deliver 1000 Watts to your charger using a non-PFC charger, you might draw more than 15 AMP on the AC side, which is more than a standard household circuit. This is why you might consider a more expensive PFC charger.
What does all this mean?
iCharger 3010B vs iCharger 306B vs FMA PowerLab 6
- First, you need to figure out how much charger you need. In general, if you are going to charge large packs (> 4S) at high C ratings (> 2C) and/or multiple packs in parallel, you could benefit from something in the 500+ watt range. With a lot of the newer packs capable of charging at 5C these days, you can really crank out a lot of amps, especially in parallel. For example, a single 2200mah 4S pack charging at 5C is 184 Watts!! (16.8V * 11A)
- Now that you think you know what you need, go ahead and add some buffer to it. Inevitably, you'll get more packs, a bigger plane in the near future that will require more charging output, or you'll start replacing packs with newer high C charge packs just so that you can do higher output charges.
- Once you have your charger picked out, pick out a power supply that makes a little more power than your charger, if possible. Remember the charger input power efficiency of 85-90% from above.
These chargers are fairly similar in price and capability. Below are the only notable differences:
- The 3010B can charge up to 10S packs, where the PL6 and 306B can only charge up to 6S packs.
- The 3010B/306B is rated 1000W at 24V (500W at 12V), where the PL6 is rated 816W at 24V (408W at 12V). To make a long story short on this stat, all 3 chargers will effectively have the same output on a 6S pack (~800 Watts). The 3010B cannot reach 1000W unless you're charging at least an 8S pack, the 306B/3010B are limited to 756 watts on 6S charging (25.2V * 30 = 756 Watts) and the PL6 is limited to 816W on a 24VDC power supply (about a 32 amp charge rate on a 6S).
- The PL6 can charge at up to 40 Amps, where the 306B/3010B can only charge at up to 30 Amps. For larger packs (> 5S), both chargers effectively will charge at the same rate because of the max wattage math from above. For 5S packs and smaller, the PL6 can charger at a higher amperage (40A) than the 306B/3010B.
- Bottom line: If you have packs over 6S, the 3010B is your only option in the group. If you only need to charge packs up to 6S in size, the PL6 is technically the most capable out of the group. If you want to save a little money over the PL6, the 306B has 95% of the capability (probably < 1 minute difference in charge time).
FMA PowerLab 8This charger has 3 distinct advantages over the 306B, 3010B, and PL6:
- The PL8 can output 1000 Watts (40 Amp charge) for 6S packs. The 306B/3010B only output 756 Watts (limited by 30A output, 30A * 25.2V) for a 6S, and the PL6 can only charge a 6S at 816W (limited by max output at 24V, ~32A output)
- If you have 7S or 8S packs, this charger can charge them at up to 1344 Watts.
- The PL8 has a higher output at 12V (612 Watts). Most of the time, you would be running your high power charger off a 24V setup. However, you may occasionally plug it into a car battery in the absence of power, or may plug it into someone else's 12V power supply at the field. In these cases, the PL8 yields an additional 100-200 watts over the 3010B, 306B, and the PL6.
First - I chose to buy from progressiverc because their website was logical and they made adding relevant items to the shopping cart easy and intuitive.
I started with "The Solution 1000w combo" http://www.progressiverc.com/the-solution-1000w-combo.html
I selected the iCharger 3010B
I went with the Mean Well RSP-1000-24 power supply - a single power supply with PFC in one box
I want to charge many batteries at the same time so I got the "Parallel Charge Board for JST-XH & T-plug" which works with the packs I get from HobbyKing and HobbyPartz. I also needed a "Parallel Charge Board for JST-XH & XT60" because I have a decent number of XT60 packs as well.
I also popped on a PRC Hardline Case with the vent holes predrilled for my powersupply. http://www.progressiverc.com/prc-hardline-cases.html I'm not sure I got a great deal on the case. I also got the "premium velcro" on the top - ensuring that I didn't get a "deal" on the case. But it looks cool.
I also added the Case Mounted AC plug and related Cable from AC Plug to power supply.
I've only used this setup for one outing, but we were charging 1 pack, 2 packs, and 3 packs (each 6s 3300 mah) at only 2c pretty quickly.
I also purchased all of my stuff from progressiverc, just because they came with great recommendations, and I'd called their owner (David, he answers the phone all the time) and asked him random questions about batteries and charging before ever buying anything from them. He knows his stuff!
I selected the PowerLab8. The main reason I chose this charger is because I wanted to be able to charge 6S packs at the full 40Amp capability of the charger. The secondary reason is that I like the higher 12V output of the charger. I have a deep cycle battery in my trailer, and it's nice to have the additional wattage in the absence of power at a field.
At first, I used one of the parallel charge boards. They are great, well built, and very tidy, but I found 2 problems. First, they are only rated at up to 30 amps. So, I couldn't charge at the 40A capability of my charger. Secondly, they are much smaller than they look (this works great for travel). When you hook up 6 packs to it, the wires are very tight together, and it's a bit of work to get everything lined up. With that said, FMA is coming out with a new board (http://www.revolectrix.com/MPA_XH.htm) that appears much larger and also supports 40A, and will likely solve both of my issues.
Shortly after getting the parallel board, I picked up parallel charge cables (http://www.progressiverc.com/parallel-6x-t-plug-charge-cable.html) and parallel balance cables (http://www.progressiverc.com/parallel-6x-balance-adapter.html). For me, they're less tidy, but easier to work with because there's more space available. Also, I can charge up to the full 40A capability of my charger :) The downside is that you need to have a set of balance cables for each LiPo cell count you plan to charge (I have 2S, 3S, 4S, and soon to be 5S parallel balance cables).
As far as power supplies, I went the cheap route and got one from FeatherMerchant (RCG thread is here). It's two 47A 12V power supplies wired in series. For $120, I got a 1200 watt power supply that has PFC. You really can't beat the price, and I haven't had a single problem (along with lots of other customers on RCG). The downsides are that it isn't as pretty/tidy and doesn't have the support/warranty of a Mean Well.
Contact Us with Questions
If you have any questions you can contact Jason Jones (iCharger) or Justin Sebastian (FMA Powerlab). It's a lot to take in, feel free to ping us with questions.