Improved our flying site

[tomlogan1]

Our flying site is located in a flood plain. As such there is no electricity. We decided to investigate solar and today, after a year of planning and a year and a half of pandemic today we went live. Ours is a very basic system: 2 210 Watt panels (420 watts) a 30 Amp Solar Charge Controller and a 200 Amp hour battery. Every source of power ( panels, battery & load) has either a 30 amp fuse or the two 30 amp circuit breakers which also serve as isolators in the event that we need to do maintenance.

We have six charging stations and think this will serve our members with no need to upgrade for years to come.

 

[Bricks]

Just curious so how many say 3S 3500mah batteries will it charge before the battery gets low or 6S- 5500`s?

 

[sprzout]

Just curious so how many say 3S 3500mah batteries will it charge before the battery gets low or 6S- 5500`s?

Generally speaking when talking about 6S batteries, most solar charging stations can't handle the load. We get guys who try to charge theirs and blow the fuses like crazy because they're trying to push too much amperage through the lines. If you're planning on doing that, we generally recommend you get a generator for your 6S to charge at the field. 3S is a little bit easier to handle, and most of the solar systems will charge those all day long.

We've had our system going for at least 5 years now without much need for maintenance - and our maintenance consists usually of replacing blown fuses and rinsing down and cleaning the solar panels once a month due to the dusty conditions (and we see the difference in power when they're dirty).

 

[Matthewdupreez]

and we see the difference in power when they're dirty

last time it was charging 10 batteries. now its only doing 7.... wash the panels

 

[PsyBorg]

Generally speaking when talking about 6S batteries, most solar charging stations can't handle the load. We get guys who try to charge theirs and blow the fuses like crazy because they're trying to push too much amperage through the lines. If you're planning on doing that, we generally recommend you get a generator for your 6S to charge at the field. 3S is a little bit easier to handle, and most of the solar systems will charge those all day long.

We've had our system going for at least 5 years now without much need for maintenance - and our maintenance consists usually of replacing blown fuses and rinsing down and cleaning the solar panels once a month due to the dusty conditions (and we see the difference in power when they're dirty).

Hrmm.... I'm surprised that cant do 6s. (solo or with others also charging is first question) the Venom Duo charger I use charged my 5s 1500mah paks at FFO18 no problem off a 60k mah lipo storage battery that over the course of the day had dropped down to 12.5 v and it still took them to 21v full capacity no problem. I charged at least 21 packs off that one storage charge over the course of the day.

I would look more at the chargers being used then the solar set up. The venom charger has an awesome step up system for field charging. Didn't even feel warm even with the open field heat at Furey field mid summer.

 

[sprzout]

Hrmm.... I'm surprised that cant do 6s. (solo or with others also charging is first question) the Venom Duo charger I use charged my 5s 1500mah paks at FFO18 no problem off a 60k mah lipo storage battery that over the course of the day had dropped down to 12.5 v and it still took them to 21v full capacity no problem. I charged at least 21 packs off that one storage charge over the course of the day.

I would look more at the chargers being used then the solar set up. The venom charger has an awesome step up system for field charging. Didn't even feel warm even with the open field heat at Furey field mid summer.

A lot of it has to do with the draw of the charging system and the full amperage. There are guys at our field that try to charge their 6S, 5000mah batteries, and the system can only do ONE battery like that at a time at 5 amps, not 4-5 chargers pulling amperage all at once. It also gets really annoying when you have to go pull the fuses and replace them because someone tried to parallel charge their 5000mah 6S batteries for their 80" Extra 300, and they're trying to charge them at 2C (we've had guys do that multiple times, after telling them NOT to do that since the system isn't designed for that much of a load, nor is it safe for their batteries).

 

[tomlogan1]

So far, so good. A few 4s batteries but only one at a time. I think we should ban parallel chargers completely. Charge one, fly one and shoot the breeze in between.

 

[LitterBug]

A lot of it has to do with the draw of the charging system and the full amperage. There are guys at our field that try to charge their 6S, 5000mah batteries, and the system can only do ONE battery like that at a time at 5 amps, not 4-5 chargers pulling amperage all at once. It also gets really annoying when you have to go pull the fuses and replace them because someone tried to parallel charge their 5000mah 6S batteries for their 80" Extra 300, and they're trying to charge them at 2C (we've had guys do that multiple times, after telling them NOT to do that since the system isn't designed for that much of a load, nor is it safe for their batteries).

Hmmm... Circuit breakers feasable instead of fuses? I have a small personal setup that is no where near that kind of load.

 

[sprzout]

So far, so good. A few 4s batteries but only one at a time. I think we should ban parallel chargers completely. Charge one, fly one and shoot the breeze in between.

That’s what most of us do when we’re charging…if people want to parallel charge, we tell them to bring a generator (and most who want to charge the big batteries do).

I personally don’t like parallel charging unless I’m charging a set of 1S batteries for my TinyWhoop; you have to be careful that all of the batteries are at the same discharged level or else you can get a battery being over charged, which can potentially result in a fire or explosion.

 

[Bricks]

That’s what most of us do when we’re charging…if people want to parallel charge, we tell them to bring a generator (and most who want to charge the big batteries do).

I personally don’t like parallel charging unless I’m charging a set of 1S batteries for my TinyWhoop; you have to be careful that all of the batteries are at the same discharged level or else you can get a battery being over charged, which can potentially result in a fire or explosion.

Please explain to me how in the above scenario charge one battery more then any of the others?

 

[Piotrsko]

Hmmm... Circuit breakers feasable instead of fuses? I have a small personal setup that is no where near that kind of load.

Fuses fault at pretty much rated current except for I2t issues then go inert requiring replacement. Circuit breakers can flow to 2X rated current before they trip. A properly biased small amperage LED across the failsafe and provide a safe indication of failure

The battery is just a buffer for clouds, cell stabilization and huge starting loads. 50 amp hours is 50,000 mah hour and you need to double the capacity of the airplane pack to account for charging inefficiencies. Divide the charged battery capacity doubled into the charge battery capacity and you have the approximate amount of batteries you can recharge.

 

[tomlogan1]

Well, we survived the first year and now are adding 2 additional panels and a 60 amp controller. We are also upgrading the wiring to 6 gauge to handle the additional amperage. Hope this is the last upgrade for a while.

 

[joelspangler]

Please explain to me how in the above scenario charge one battery more then any of the others?

Say you have one really discharged battery at like 3.2 volts, and five others that have 3.8 or 3,9 volts each. When you hook them in parallel, the ones with higher voltage are going to try to equalize with the low battery. This can push a fairly high amperage of current into the low battery - possibly at a few c's of charge. This is exacerbated by starting the charger before they equalize - if you set it to a rate of 1c on all batteries, and you have 6 in parallel, you'll be pushing 6c into the battery until it's caught up with the others... this is in addition to the 5 other batteries pushing current into the battery with lower voltage. You can easily cause damage to the low cell by it trying to charge too fast. The low cell will almost certainly get hot, and it might swell, or even catch on fire.

I parallel charge, but ONLY with batteries that were properly storage charged. I also always check each battery before hooking together (to verify that I didn't get fully charged mixed up with uncharged batteries), and that the cells didn't self-discharge while in storage. If the batteries are any more than 0.10v different than one-another, I don't charge them together.