1 Big and 1 Small Inverter

[ywhic]

Noticed this in another post.. and someone mentioned they have 2 inverters..

1 for large loads and 1 for small loads..

I know I can split my breaker panel in 1/2 and use 1 leg for the small and 1 leg for the big stuff.

It has a separate BACKBONE for the LOAD leads..

I have an incoming 2000 watt pure sine inverter (0.3-0.8A no-load).. which I had intended to run 'everything' in my little cabin..

None of my loads will be over the 2000w continuos even pretty much all turned on..

My items in use daily..

Fridge TBD
Water Pump 90w max (and on a pressure switch and manual switch..)
2-13w CFL's
1-14w laptop
1-Accubreeze Celing fan 10-68 watts
1-TV 45 watts

Should I run with the single 2000w or should I also buy a smaller 1000w pure sine for the smaller stuff.??

The difference is $100 between the 1000w and the 2000w.. maybe I should buy another 2000w??

Whats setups do you folks RUN/USE in your buildings/cabins/sheds/garages??

[Dill]

300W Morningstar 300 (super low idle usage) and I plan on moving my ProWatt SW 1000 to the cabin for the bigger stuff. The ProWatt will be off probably 97% of the time.

[Cariboocoot]

Al;

When you split inverter loads up like that it's generally using something like a Morningstar 300 for the little things (very small draw in search mode for those items that are on only as needed) and a bigger (1kW or more) inverter for the large loads - providing they can be used selectively.

That's the trick; how well can you control load use? Things that need power on demand like refrigerators can make a mess of the plan. If the big inverter is going to have to be on/available anyway - what's the point in having a small one?

Somewhere on here I went through the rigamarole with my wife's suggestion of a separate small inverter for the office. The cost of buying the extra equipment for the dual system could also expand the large system so that the energy draw was not an issue. Likewise I have tried my inverter in search mode and found what it saved in energy per day wasn't that much due to the repeat demands of switching on the 'frige.

That is a big one: refrigeration. For the most part if you run an electric 'frige the small inverter will be of no use and the large one will have to be available all the time anyway.

It's a bit different from starting a 5kW gen to run the washing machine while using a 1 kW inverter to run everything else. You really have to figure out your loads and how you will use them.

[Wxboy]

Al, did you order a specific model or do you just know you are getting a 2000 watt inverter? I know you've been bouncing back and forth between different models so I'm just curious if you made a final decision. I can't see much of an advantage to having 2 inverters other than having a backup if one goes down. If you are running both inverters at the same time you would be drawing more idle current than just running one. If you want 2 inverters I personally would get another 2000 for only $100 difference. That way either inverter can run the entire system. There isn't that much of a difference in no-load draw between a 1000 and a 2000. But I would start with one and see how it goes before buying a second. My first Prowatt 2000 did have a problem so I can see the value in having a backup on standby but only if money allows. Mine just happened to die before a 7 day power outage so I had to use my modified sine wave Cobra inverter. Thankfully I had a backup but I wish I had the pure sine wave inverter for the outage because I didn't want to run my lcd tv on the msw since the tv makes a buzzing noise on that inverter. This was before I had my small solar setup so I used my Prius to run what I needed.

[ywhic]

@ Wxboy.. Yes I ordered the Xantrex ProWatt SW 2000 and it will be in-hand Tuesday..

I will have some money coming in now as I am back to work.. and was thinking outloud about a 2nd inverter..

I was thinking the Fridge and Water Pump on one unit.. and per se the Kitchen circuit..

Then another unit for the 'rest'..

The only other appliances I can possibly see to be used would be either a small 700w Microwave or 900/1200w hot plate..

Hence the possibility of splitting the loads..

Kitchen (Fridge, Water Pump, Microwave).. The 'rest' on another.. I was thinking a 1000 watt Xantrex ProWatt for that since the no-load consumption is also low.. Though true a 2nd 2000w model couldn't hurt..

[waynefromnscanada]

I have one Morningstar 300 on 24/7. Runs ALL my lights inside and out, computer, TV & Sat receiver, chargers, air exchanger and a bunch of other stuff.
The Prowatt 1800 is only ever on for the very few heavy loads, when they need power.

[ywhic]

Well if we could figure a ballpark on what a normal fridge runs in AMPS to start...

I know the MS300 would run all the small stuff.. the problem I have would be the fridge, the microwave, and then during the super-hot days the A/C unit.. which we have found out will run on the 2000W Xantrex.. (thanks to 2manytoys)..

The question would be if the fridge kicks on will the A/C unit go off if I put them on the same 2K inverter??

Would a chest freezer be better than a fridge for my (South TX) situation??

[2manytoyz]

None of my loads will be over the 2000w continuos even pretty much all turned on..

Keep in mind the 2000W rating is for 5 minutes. The Prowatt SW2000 is rated for 1800W continuous. Even at that rate, that's a massive amount of energy from the battery bank. Short - heavy loads are fine, things like a microwave oven. Running it near capacity for long, you'd need a very large battery bank indeed.

I've run multiple inverters at my last house, but that was a different setup. I ran CFL lighting from a 400W MSW inverter. I used a remote setup to turn the inverter on/off as needed. No parasitic load with the inverter off. I had grid power most of the time, so that ran my fridge and the rest of the house. When the grid went down (common issue in FL), the loads transferred to a Prosine 1800W inverter in the Power Save mode. When it detected a load, it powered up and ran the appliances. When the grid came back online, the loads transferred back, and the Prosine went back to sleep.

The parasitic load of the Prosine was significant when left powered up all the time (not in power save mode). So in that case, it made more sense to use two inverters.

The new Prowatt SW2000 doesn't have a Power Save feature, but it has a very low idle current. Consequently, I no longer have a need to run a second, smaller inverter.

I did keep the older Prosine, and it's wired up next to the Prowatt. It has a separate power feed, 250A fuse, and Blue Sea switch. It can be powered up if needed to run another heavy load, or in case one inverter has a failure (unlikely, but possible). Hurricane season is here, and having a Plan B is a good thing!

[waynefromnscanada]

The question would be if the fridge kicks on will the A/C unit go off if I put them on the same 2K inverter??

Would a chest freezer be better than a fridge for my (South TX) situation??

The AC won't go off when the fridge starts, UNLESS you have a relay to remove it's power whenever the fridge starts. Depending on the AC power requirement, as well as the start surge of the fridge, AND the surge capacity of the inverter, the combined load MIGHT overload the inverter and cause it to shut down.
Chest freezer converted to fridge won't let the cold air flow out when you open the door, but it quickly becomes a pain in the butt to have to dig down to the bottom to find those leftovers from 3 wks ago. Been there, done that.

[Wxboy]

If the AC is running and the fridge compressor kicks in I think you would be fine. The AC running should be around 500 watts give or take and the surge of the fridge starting might be 1,000-1,200 watts(again approx.) so that's well within the limit of the inverter even with other small loads running. Now if the two tried to kick on at the exact same time that would cause a problem but that may be unlikely???