2 6000 watt inverter or 1 12000 watt inverter, Pro's Con's?

[FLSolar]

What are the pros and cons to using either 2 6000 watt inverter compared to 1 12000 watt?

 

[DestroyFX]

For one thing, You will need one circuit per invertor (isolated circuits).
Or get inverters than can be synchronized to be in phase.

Probably simpler to just get one good inverter.

 

[pollenface]

Depends on what you're doing with them. Can you be more specific?

 

[LywWyr]

I chose 2 smaller inverters for redundancy, and future expansion. If 1 inverter goes down I can still run my critical loads. I am off grid in Mexico so getting parts is not an easy task.

 

[John Frum]

What are the pros and cons to using either 2 6000 watt inverter compared to 1 12000 watt?

For North America, a 12000 watt inverter should be 48 volts dc and produce 120/240VAC split phase power at 60hz.
It will also likely be an inverter/charger or all in one.
A 6000 watt inverter could be 120VAC or 120/240VAC at 60hz.
Some of them support syncronization so that 2 of them provide either 12000 watts at 120VAC or 12000 watts at 120/240VAC.
It could be 24 or 48 volts DC.

12000 watts / .85 conversion factor / 48 volts = 294.117647059 service amps
That requires a 400 amp fuse and 4/0 wire for the main circuit.
300 service amps is a lot of current.

12000 watts / .85 conversion factor / 24 volts = 588.235294118 service amps
That requires 2x 4/0 wire each with a 400 amp fuse for the main circuit.
600 service amps is nuts.

 

[FLSolar]

Depends on what you're doing with them. Can you be more specific?

I want to run my freezers and some lights initially and expand later

 

[MichaelK]

A single 6000W inverter is likely to have lower background consumption then a 12k inverter, though I would guess that two 6000W inverters on at the same time might have higher consumption. This of course will be brand/model specific.

The reasons I would chose for having it is 1) redundancy, 2) capacity, and 3) split-phase 120/240VAC.

One scenario that a neighbor is thinking about now is creating a smaller starter system just to get lights on, then upgrade in the future with a second unit that will allow him to run his 240V well pump.

 

[PlaneBatteries]

Keep in mind some of the single 240 inverters do not like big amp splits on the separate phases such as an ac unit starting up or a compressor etc. Having two separate inverters takes care of this providing the surge is within it's tolerances. I run 2 of the 6548 @ 6500 w each and it takes the 3 ton ac and 1 hp well pump with no issues. The only time I have an issue is when the ac and the pump decide to come on at once and it's the BMS on the batteries that kick off.

 

[anadiner]

What are the pros and cons to using either 2 6000 watt inverter compared to 1 12000 watt?

Im all about multiple so I say 2. I just don't like depending on 1 item. It goes then nothing. That's just me and simple answer.

PS Ive even broken things down to dedicated 24vs but once again, that's me.

 

[Rednecktek]

Keep in mind some of the single 240 inverters do not like big amp splits on the separate phases such as an ac unit starting up or a compressor etc. Having two separate inverters takes care of this providing the surge is within it's tolerances. I run 2 of the 6548 @ 6500 w each and it takes the 3 ton ac and 1 hp well pump with no issues. The only time I have an issue is when the ac and the pump decide to come on at once and it's the BMS on the batteries that kick off.

Just to throw the info out there as something to consider, if you're running dual inverters in split-phase and 1 of them dies, any 240v devices that try to fire up (aircon, well pump, etc) will try to fire up anyways and just draw WAY more amps than they usually do (single-phasing) which usually blows a breaker at the very least and may or may not fry an AIO.

Pro's: Lights will stay on if 1 unit dies
Con's: If you're not there to stop it heavy 240v loads could damage remaining components.

It's a crap shoot.

 

[SparkyJJO]

Just to throw the info out there as something to consider, if you're running dual inverters in split-phase and 1 of them dies, any 240v devices that try to fire up (aircon, well pump, etc) will try to fire up anyways and just draw WAY more amps than they usually do (single-phasing) which usually blows a breaker at the very least and may or may not fry an AIO.

Pro's: Lights will stay on if 1 unit dies
Con's: If you're not there to stop it heavy 240v loads could damage remaining components.

It's a crap shoot.

Well, it depends on how the two work together. If each inverter is only 120V and to get 240V you run two inverters, if one dies, you lose an entire leg. So half your lights go out and your 240V stuff just won't work at all. Kinda like what happened at my old house when one wire pulled out of the transformer on the pole during a storm. My dryer shut down with a click and half the house went dark.

 

[Rednecktek]

My well pump had a loose connection at one point and when the pressure switch kicked on it tried to pull ALL the amps from the single leg which overloaded and tripped my generator. The generator is more forgiving than modern AIO's probably.

Just wanted to make sure it was in the "Things To Consider" list.

 

[SparkyJJO]

I bet the loose connection was resulting in a partial, higher resistance connection. AC induction motors will drive the amps up if the voltage sags to maintain RPM, as RPM is determined by the AC frequency and winding of the motor. That's why you can't use a traditional rheostat type dimmer switch on those motors as it won't really slow the motor down very well but can burn out the windings due to an overcurrent condition.

If one leg totally drops off it becomes open circuit and simply won't run at that point.