Setting up my first system

[Twotaps]

So I am setting up my first system and was wondeing if you guys will read over it and give me some feed back.

Grape solar GS-S-250 fab5
Renogy 20amp MPPT charge controller
2Trojan t105s (I suspect this will be too much battery for the panel)
inverter??????
Im a tad lost still as to how to hardwire things to an inverter. All the ones I look at have plugs or am I missing something??? Is there a sticky somewhere I could read over??


Here is what I plan to run
Takagi TK Jr propane tankless hot water heater : pulls 2 amps AC at full draw (will be the only thing on the inverter )
Sureflo quiet quad 2 : pulls 2.8 amps DC at full draw.
Fan tastic vent fan : pulls 1.9 amps DC at full draw


These will all only run for about an hour a day max. Sometimes much less. Could I get some input on what inverter to get? And any other advise/input on the rest of the parts.

[Mike90250]

Whoa !

Before you do another thing, you need to calculate your LOADS. What is your system supposed to do? Pumping water for 5 hours a day, is a very different system for recharging a laptop.
EVERYTHING revolves around the daily load, and how critical is is to run it, in case of a cloudy day.
You can spend a LOT of money for a overly large system, or spend a little money for a disappointingly small system that can't run your loads.
Gasoline is a very dense energy source, solar is not dense at all, and it takes many PV panels to equal the power of 1 gallon of fuel.

[Mike90250]

Takagi TK Jr propane tankless hot water heater : pulls 2 amps AC at full draw (will be the only thing on the inverter )
Sureflo quiet quad 2 : pulls 2.8 amps DC at full draw.
Fan tastic vent fan : pulls 1.9 amps DC at full draw

If all these loads run for 3 minutes a day, this is a very minor system, If the heater runs 90 minutes (1.5 hours), Sureflo for 0.5hr and fan for 4 hours, that is a very different sort of load.

There are stickies that describe the load calculating process,

The first bit of advice, is to calculate loads in Watt Hours, because 120VAC @ 2A is very different from 12Vdc @ 2.8 amps

here are the stickies for you:

https://www.solarpaneltalk.com/forum/off-grid-solar/off-grid-solar-panel-systems

[Twotaps]

So my load would be Takagi is 120v x 2amp x 1hour/day = 240 watt hours. Pump is 2.8amps x 12 volt x 1hour= 33.6 watt hours.
Fan is 1.9amps x 12volt x 2hours = 45.6 watt hours. Total load of 319.2 watt hours per day. Is that even correct? I'm sure there is also system losses too. I'm sure it can't be that straight foreword.
I'm also thinking my battery is twice as big as needed.

[Mike90250]

So my load would be
Takagi is 120v x 2amp x 1hour/day = 240 watt hours.
Pump is 2.8amps x 12 volt x 1hour= 33.6 watt hours.
Fan is 1.9amps x 12volt x 2hours = 45.6 watt hours.

Total load of 319.2 watt hours per day. Is that even correct? I'm sure there is also system losses too. I'm sure it can't be that straight foreword.
I'm also thinking my battery is twice as big as needed.

So, you have to run an inverter, Morningstar makes a very nice 300w inverter (600w surge) that is very low loss,
Batteries recharge at about 80% efficient, take out 300 watt hours, replace with 360watt hours.
Panels run 80% of nameplate
You size your battery to only go down 20% per day, and start your generator on the 3rd day

320 wh needed x 5 = 3200wh.
6v, 180ah battery (golf cart, $90) = 1080wh, So you need 3 of those batteries, which is an odd ball voltage, so you add one more for a 2s x 2p 12V setup.
12V @ 360ah needs roughly 35A to recharge with, about 600W of PV
And it's late at night, babysitting grandkids for a week, and I may have brain fade

[Wy_White_Wolf]

"320 wh needed x 5 = 3200wh"

Late indeed. That would be 1600wh so his 2 batteries would be appropriate and might give him 3 days autonomy instead of 2.

The 250w panel through a 20A MPPT should be sufficient to charge the battery. It's a little on the low side but should be OK.

WWW

[Twotaps]

So, you have to run an inverter, Morningstar makes a very nice 300w inverter (600w surge)

I was looking at that inverter but if everything is running at once wouldn't it exceed the 300 watts the inverter is rated for?

[Mike90250]

from what you wrote, the water heater is the only 120VAC appliance, you listed the others as 12VDC and therefor would run off the battery.

[Twotaps]

Oh. ..Bahaha. of course

[Twotaps]

If i hardwire the heater to the inverter I should run it through a breaker box or a fuse correct?

[Mike90250]

The 300w suresine could be wired to a small panel box, with a small breaker for each appliance on it, But I for sure, would have a breaker on it.