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Re: inverter circuit breaker panel question

Reply #25 – August 15, 2019, 12:53:57 am

When I bought the coach it had been upgraded to a 3000 watt inverter by Ron Hawkins' business, Innovative Coach Works Kansas maybe the wires have been upgraded too. What gauge wire from the inverter to the panel should there be. It looks like welding cable from the batteries to the inverter. I can check their ga. tomorrow. Everything has been working fine since I bought it in 2015.

 This was his personal coach.

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Re: inverter circuit breaker panel question

Reply #26 – August 15, 2019, 09:06:53 am

inverter wars "crop dusting" has been (and will continue to be) deleted.  Poster has been warned.

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Re: inverter circuit breaker panel question

Reply #27 – August 15, 2019, 09:28:38 am

Thanks Michelle for tidying up.

Chuck, the original inverter/charger probably had 3/0 cable from the power posts behind the white panel in your main bay to the inverter.  These feed power to the inverter to create 120v or get power from the charger to charge the battery.  As chargers and inverters get bigger so does the requirements for wiring.  My Victron uses two incoming 3/0 plus and minus cables.

The OEM 120v wiring from the main panel to the inverter is sized for 20 amps and has a 20 amp circuit breaker (in mine and likely most coaches of this vintage). This is plenty to run the OEM chargers.  Newer chargers that can do 120 amps are OK with that size wires (most likely 12 ga)

On the inverter output side a 2400 watt inverter can put out 20 amps and more in surge.  I think FT used 10 ga wire on the output side to the inverter sub panel.  Bigger inverters can generate more watts and more 120v amps which means bigger wires are needed.

If you want to get rid of the OEM ATS used by the inverter and pass 50 amps from the land line through the inverter and its internal transfer switch to the inverter sub panel then the main panel circuit breaker to the inverter needs to be 50 amps, the wiring needs to be much bigger to the inverter and much bigger from the inverter back to the inverter sub panel.  Maybe 4 ga.  And if you have a Victron Multiplus or a Magnum Hybrid that can pass through power and invert at the same time then maybe even bigger.  The Victron will pass through 50 amps and invert to add another 14 amp (about).  For that, wiring to the inverter sub panel and the circuit breaker in the inverter sub panel need to be even bigger.  And most folks forget that you should add a circuit breaker panel close to the inverter with an appropriately sized circuit breaker for this source. 

Someday I will get around to this. Rght now I use the sub panel powered by the main panel through the existing ATS.  Part of the challenge is wiring routes and the space available in the sub floor cavities into the space at the end of the bed. It is very tight.

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Re: inverter circuit breaker panel question

Reply #28 – August 15, 2019, 11:26:35 am

Roger,
I am happy the way it is wired now. I have never needed the output power of the SW 3012, but 3000 watts came with the coach. If it had the multi-plus, I wouldn't even be going the small inverter at this time. We make it through the night with 3, 6 year old Lifeline AGM's and 1/2 hour of generator time. Some days no generator at all.  I am preparing for the future when I have the 6th panel up and 6 335-6 batteries. At that time I want to be able to not need the generator except under hot days when air is needed. The low idle inverter will be of much help then.
 Thanks again for your input on this project.

Chuck

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Re: inverter circuit breaker panel question

Reply #29 – August 15, 2019, 01:32:43 pm

Craneman, most likely the way your rv is wired, you are only using one half of the capability of the SW3012, so you do not really have 3000 watts available, however you do have a great unit with 150 watt charger with many changeable settings thru the remote. 

To see if you are using the entire 3000 watt capability you would have to look at the AC input and output connectors on the SW3012.  I would expect for you to see only one of the two line inputs and only one of the two outputs being used.

Those interested may check out the attached manual for the SW3012 and the installation guide for the SW units from Xantrex.  In order to get 3000 watts from the SW3012 you need to use both line inputs of 120 V line inputs from the 50 amp service coming in.  See the attachment for the manual, the section on wiring the AC input and output of the SW3012.

I have owned two SW3012 in previous rvs, and found them excellent, however because of the rv wiring in the two Monaco Signatures, I used only one line of the two line inputs from the 50 amps coming in. 

When I bought my current FT I chose the SW2012 as I knew I would only need it's 30 amp AC input and output for the FT wiring.

To be fair in comparing the two, the SW3012 has a 150 amp charger, the SW2012 a 100 amp charger.  Given the choice again I would choose the SW3012 for the larger charger over my current SW2012.  I also attached remote instructions to get an idea of how flexible your SW3012 is thru the remote control.

If ever having trouble with the SW3012 after changing settings you can load the defaults by doing so thru the remote.  At one time I had created an issue after changing the low inverter cutout from 10.5 to 11.8.  I had to change back to the 10.5 default.  My issue was when I ran the toaster along with the microwave, the inverter would shut down as it saw less than 11.8V.  At the default 10.5 all is fine.

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Re: inverter circuit breaker panel question

Reply #30 – August 15, 2019, 03:17:13 pm

You are right, it is only using one input and one output. I read the information back when I first got the coach and decided 1500 watts was more than I needed so left the wiring alone. It has no problem with the microwave or the Cuisinart coffee maker in the mornings. I do like the fast charging, my only gripe is the power it draws at idle at night. If I ever want to do one of the mods posted about running the front air while driving without the generator I will add the needed wiring at that time.

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Re: inverter circuit breaker panel question

Reply #31 – August 15, 2019, 04:31:57 pm

Don't know if this will help or if your coach is wired the same but my coach has a double outlet in the refrigerator compartment. Each is on a separate circuit. I don't run my refrigerator on AC unless I am hooked up to shore power. I disconnected one circuit from the panel (that powers the inside and kitchen outlets as well as the outside outlet and one of the refrigerator outlets) and use an inverter to power that circuit. 

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