2nd INVERTER ?

Re: 2nd INVERTER ?

clam wrote: »

130 watt Vmp 18.00,Imp 7.22.
175 watt Vmp 35.80,Imp 4.90.

You can certainly place the two 130 watt panels in series, then in parallel with single 175 watt panels (18+18=36 volts vs 35.8 volts--virtually the same Vmp for the array).

Sunforce 1000 watt inverter...255 watts draw
Dell desktop 200 watts draw
Panasonic HDTV 110 watts draw
Led lights 3 watts draw

Sunforce 30 Controller, not inverter (oops!)

In general, I highly recommend that you look at conservation first. The 200 watt desktop + 110 watt monitor may be replaced by a 30-50 watt laptop. A huge win.

You can always compare the cost of a new laptop vs the cost of building out a solar PV system that has to be 5-10x larger to meet your needs.

Is the gain greater from installing the Rogue to service the 130 watt panels vis a vis the loss of power from mixing the 130's and 175's on the Flexmax 80?

Don't bother with a new controller--You can run your pair of 130 watt panels in series for the same Vmp as a single 175 watt panel.

For charging a 24 volt battery system, the 80 amp Outback controller is good for:

• 80 amps * 29 volts battery charging * 1/0.77 panel+controller derating = 3,013 watts maximum (cost effective) solar array

Also, you could put 2x 175 watt panels in series (and 4x 130 watt panels in series) and connect the entire ~72 Volt Vmp to your Outback (maximum Vmp~100 VDC input for many climates).

Having a high voltage Vmp array can save you lots of cost on copper wiring from the array to the controller/battery shed.

In my case, would having 2 controllers give greater power than one controller?

Not really... Stay with the one large controller unless you are looking for backup power or just want to do some lab time with another brand/model. (Rogue is a very nice/cost effective controller with great support from the designer).

Also adding new batteries to old ,(I have just read from your site), is not a good idea.
Therefore adding new batteries would have a bias,to 2 controllers,as separate entities?

Adding batteries is always a personal choice... In theory, worst case, the new batteries may age out about the same time as the older batteries.

Or, you will end up piece part replacing batteries one or two at a time as they wear out over the period of several years. A pain in itself (sort of always running with a 1/2 crippled bank).

Otherwise, if your present bank is too small to support your needs--you need to do something. Adding batteries may not be the worst thing in the world.

I have just run out of power,due to 2 days of overcast skies.It has taken me about 3 days to charge the batts.Had to go to an old laptop )

Ideally, we recommend 1-3 days of "no sun" backup power and running the bank down to 50% state of charge.

You have to measure your "observed capacity" vs name plate capacity... If the batteries are at 2/3 or 1/2 of rated capacity--they probably are going to need replacement anyway.

And you always have the choice of "cheap" golf cart batteries or expensive/nice deep cycle. From what little I have read, it works out that the 2x more expensive batteries will last about 2x as long as the "cheap" batteries. So, no win there (other than fewer change outs over the years).

If you are still playing and learning about your system and golf cart batteries last 3-5 years on your system--May be worth sticking with the older batteries so you can "upgrade" as needed 3-5 years down the road as you get more experience with the system and your needs.

I feel I need to add two 175's (4 total) to the Flemax and add two new GC2 220 amp hr batteries connected to a new Rogue controller (saw it on your site),as a separate system.

Just to be clear, the moderators are not connected with NAWS (Northern Arizona Wind and Sun, our host), or any other solar related Mfg/Sales organization.

The two Admins (Windsun and Rick) are from NAWS. And a few other posters here are designers/support staff from a few other vendors/mfg, and speak for themselves.

Rogue is not sold by NAWS, but direct from his own site (www.roguepowertech.com).

The Rogue unit is in its second version now--with some nice additions (I really like the remote voltage sense leads). It has been a solid performer and a good cost point (and the digital display is not an $$$ option).

Once the Flexmax 80 and the 175's run out then switch to the Rogue 30 and 130 watt panels ???

I like to keep solar PV systems "unified" into one larger system instead of breaking them up into several smaller system powering one site/home/cabin.

It makes you get into balancing power usage across several systems--More work that it is worth (in my humble opinion).

Thank you very much for your professional response and expert advice.

Who 'dat? :roll:

Have fun!
-Bill

Re: 2nd INVERTER ?

The question of two vs one battery banks... For a home, I would say one.

For a boat--you tell me. Do you want two separate banks for emergency backup (ocean going sailboat), or would one good sized bank with solar+backup genset of some sort be good enough for the house battery (plus a second battery enough to start the motor/run the navigation lights for a house boat)?

The only reason to split the solar array is because you NEED two separate battery banks. Otherwise, you can always run one main house bank and even get a small battery charger to recharge the motor/start battery bank (several types available).

Again, being limited in solar power space, changing over to energy conservation type laptop (and second monitor, if needed) is a much better way to go unless you have backup shore power for much of your normal usage (and/or the computer is not used 8-12 hours a day but only a couple hours a day instead).

-Bill