Trouble matching controllers to panels.

[SunEagle]

This is what I have right now, the panels are over 10 years old so I want to replace them.

8 x 6volt deep cycle batteries -- http://usbattery.com/products/6-volt...s-2200-xc2-lf/

2 x 1500 watt 12volt to 120volt inverters

2 x 2000E blue sky solar boost charge controllers -- http://www.blueskyenergyinc.com/prod...ar_boost_2000e

If you have those 8 x 6v 232Ah batteries wired as a 12volt system then you have over 900Ah which requires about 90amp of charging capability. So you need at least an 80Amp MPPT charge controller and about 1000 watts of solar panels.

Not sure if you really need a 12volt 923Ah battery system but wiring 4 sets of 2 x 6v in parallel will result in uneven charging and discharging of a couple of those 6volt batteries.

Maybe cut the number of batteries to 4 and work on a 460Ah 12volt battery system. Then you could get by with a 45amp MPPT CC or 60A.

[plantian]

This is what I have right now, the panels are over 10 years old so I want to replace them.

8 x 6volt deep cycle batteries -- http://usbattery.com/products/6-volt...s-2200-xc2-lf/

2 x 1500 watt 12volt to 120volt inverters

2 x 2000E blue sky solar boost charge controllers -- http://www.blueskyenergyinc.com/prod...ar_boost_2000e

[Bucho]

Yeah, they don't seem very modern but I already have 2 x 2000E blue sky controllers and 2 x 12v inverters. Doesn't seem cost effective to just toss them although I'm kind of limiting my ability to expand by staying 12volt. If I rewire everything for 24volts I have to get new inverters, new wiring and a new charge controller in addition to new panels. Could you recommend a better controller setup for just 12volts?

Can you tell me all the equipment you have?

[plantian]

Yeah, they don't seem very modern but I already have 2 x 2000E blue sky controllers and 2 x 12v inverters. Doesn't seem cost effective to just toss them although I'm kind of limiting my ability to expand by staying 12volt. If I rewire everything for 24volts I have to get new inverters, new wiring and a new charge controller in addition to new panels. Could you recommend a better controller setup for just 12volts?

[Bucho]

Although it is considered MPPT it only accepts up to 30V PV input and would only support a 12V battery bank...

Wow, the more I look at these controllers the more they don't seem like good money.

[Bucho]

I think with charge controllers the amp rating you see is the max charging amps, not necessarily the max input amps.

It's both, you can't put more than 30amps into a 30amp charge controller. Decent controllers also won't convert more volts into amps than they can handle so you can over panel them and *shrug* some power will get wasted at noon on a nice day.

[plantian]

DC Breaker

Is using a dc-breaker, as seen in my prior attachment, total over-kill for a 18V x 20A line ? Anyone have any good links on wiring diagrams for small solar setups?

[plantian]

Instead of 2 @ 150w why not one @300w it will be more efficient and cheaper ; your mppt cc will take that easy.

Is it more efficient because there is less wiring?

I don't know I hadn't thought about it but I was probably going to get them on amazon and I only see a 150W. Also would a 300W be huge and hard to install? Seems like the 150W might be difficult as it is. Also it kind of spreads my risk out if someone goes wrong with one of the panels. Almost where having 3 x 100 W might be even more safe and easy to install but seems not worth the wiring.

[Raul]

Instead of 2 @ 150w why not one @300w it will be more efficient and cheaper ; your mppt cc will take that easy.

[plantian]

Drawing Of Setup

Thanks for the help guys. So it sounds like I can use multiple 2000E controllers. It turns out 2 x 150 W panels are cheaper than the 3 x 100W panels so I think I'm going to go that route. The calculations should be about the same so based on what you guys said I should be okay.

If anyone has time could you critique my draw-up of the components I will use and how they are layed out? (Solar.jpg)

If I have 2 controllers on the same bank at what point do I have to worry about some max current situation over-loading the wiring or the batteries themselves? Ie. Does the chargers' current add up ? 25A + 25A = 50A?

Specifically if I have 30AMP rated wiring from the panels to the chargers that should be well within the 25A short circuit condition, but what wiring do I need from the controllers to the batteries, 50A rated?? Do I have to worry about having my inverters connected to the same wiring as the wiring between the chargers and the batteries?

Thanks for your help,

- Ian

[Wy_White_Wolf]

1. It's an MPPT controller so watts in equals watts out. 25A * 12Vdc = 300watts. The charge controller can only handle 3 panels.

2. If both controllers are the same and set to the same battery type there shouldn't be any major problems. There might be some minor ones created by one controller delaying to switch from bulk to absorb to float at slightly different voltages but they are usually minor as the batteries are already mostly charged.

3. It's a 30A controller. While the math only works out to 360 watts the listing claims 400 watts so it can handle 1 more panel. Other than that I could Couldn't find the full specifications to note any other differences.

WWW

[cmclane28]

Hi Guys,

I've been reading about panels for a small business setup and I'm not making a lot of progress. I'd like to use a blue sky energy controller because I have used them before and they have lasted a very long time in abysmal conditions. I'm hoping someone could double check my understanding on 3 points.


Point 1: How many 100 watt panels can I connect to this controller?

Is this right: 4 panels x 5.29A = ~21A because 21A < 25A which is the controller's max.

100W 12V Panel (5.29A/short circuit 5.75A):

http://www.amazon.com/RENOGY-Monocrystalline-Photovoltaic-Battery-Charging/dp/B009Z6CW7O/

2000E Controller:

http://www.amazon.com/Blue-Sky-Energy-Charge-Controller/dp/B007S1N3F8/

Point 2: Now if I want to have 2 of these controllers, the 2000E, connected to the same set of batteries will they conflict because they don't support a master/slave configuration?


Point 3: What is the difference between the 2000E and the 3000i?

It seems like they'd both only support 4 of the 100Watt panels above.

3000i Controller:

http://www.amazon.com/Solar-Boost-3000i-Controller-SB3000i/dp/B00LCCDH5K/

Thanks for your time,

- Ian

I think with charge controllers the amp rating you see is the max charging amps, not necessarily the max input amps. I just looked up the specs of the controller on their website. Although it is considered MPPT it only accepts up to 30V PV input and would only support a 12V battery bank, If the charging amps is only 25A max and the bank is 1 V I think that means the max input wattage for that controller is only around 300 watts so 4 - 100 watt panels is going to be too much for a single controller. You should be able to put 3 on it, but I wouldn't push the upper limit. You will need two of them with 2 panels connected in parallel to each controller. I'm not sure about connecting them to the same bank, but usually that's not a problem if you are using the same make and model controllers.

The 3000i model appears to have a 30 amp charge rate, which should mean the total input wattage couldn't exceed 360 watts.

[plantian]

Hi Guys,

I've been reading about panels for a small business setup and I'm not making a lot of progress. I'd like to use a blue sky energy controller because I have used them before and they have lasted a very long time in abysmal conditions. I'm hoping someone could double check my understanding on 3 points.


Point 1: How many 100 watt panels can I connect to this controller?

Is this right: 4 panels x 5.29A = ~21A because 21A < 25A which is the controller's max.

100W 12V Panel (5.29A/short circuit 5.75A):

http://www.amazon.com/RENOGY-Monocrystalline-Photovoltaic-Battery-Charging/dp/B009Z6CW7O/

2000E Controller:

http://www.amazon.com/Blue-Sky-Energy-Charge-Controller/dp/B007S1N3F8/

Point 2: Now if I want to have 2 of these controllers, the 2000E, connected to the same set of batteries will they conflict because they don't support a master/slave configuration?


Point 3: What is the difference between the 2000E and the 3000i?

It seems like they'd both only support 4 of the 100Watt panels above.

3000i Controller:

http://www.amazon.com/Solar-Boost-3000i-Controller-SB3000i/dp/B00LCCDH5K/

Thanks for your time,

- Ian