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HHIDan · 02-06-2015, 06:58 AM

I just finished replacing my Norcold for a Samsung RF18. I want to upgrade my Inverter to a True Sine Wave mostly as a precaution as everything seems to work fine (except my alarm clock).

First question that comes to mind, is 2000 watts still sufficient?? The new refrigerator does not surge on power up and when cycling...

I currently have a ME2012 (2000 watts modified sine) and would be considering:
Magnum MS2012 (2000 watts true sine). (about $1250)
or
Magnum MS2812 (2800 watts true sine). (about $1450)
and there is a MSH3012 (3000 watts, about $1650) which is a Hybrid and will combine current from shore + available current from batts. which is an interesting concept but I have a 7500 watt genset...

In my current install I have two AC wires connected to the inverter, both are AWG 10/2, one comes from the main panel out from a 30A single pole breaker and the second one from the inverter goes to the inverter sub panel in thru a single pole 30A breaker.

If I decide to go 2800 watts, I believe I need to replace the AC wires and breakers right? (Not that difficult to do in my install...) What size wire/breaker?

Will I need to also upgrade the DC wires going to the battery bank and the DC fuse? This will be more difficult as I would be going over the rear wheels (tag axle) to the rear of the battery compartment? I am planning on most likely not increasing the battery bank (4 X 6V) as we never boondock more than an overnight. If I decide to go with 6 batteries then I suppose it's more current, larger wires?

If I decide to increase the battery bank I am thinking of moving the engine batteries into the engine compartment in order to free up the space for two more coach batteries...

As usual, I would appreciate ideas and comments.. TIA

Algoma · 02-06-2015, 07:09 AM

If you look at current Newmar specs. it shows a 2000 watt inverter with the residential fridge and 2800 watt if you go all electric. Unless you intend to add more devices on the inverted a/c output you won't actually draw any more current from the batteries using the 2800 than the 2000, you will just have some reserve if needed. You are right that the battery cables would need to be upgraded if you use the extra power but you can add extra cables in parallel to the existing ones instead of replacing the originals.

newmar10 · 02-06-2015, 07:32 AM

I changed mine 2years ago from an me2012 to a ms2012 when I did the fridge change over. I did not go with a Samsung went with an Lg as it was larger and we had room in are 4086. Was a very simple change over

PDR John · 02-06-2015, 09:17 AM

The 2000 watt will do you just fine. It will handle the loads you intend to put on without issue.

HHIDan · 02-06-2015, 10:59 AM

(I am OP)
After I posted, I started wondering why the wires and external breakers (on panels) would be 30 amps (3000 watts) for an inverter rated at 2000... I went back to the coach to look at inverter again and I see that there are push-button breakers on the inverter itself. 30 amp on input and 20 amps on output. So in standby mode there is 30 amps that can go thru (from shore or gen) but in inverter mode only 20 amps can come out.

So I think that I can assume the wires and external breakers rated for 30 A are fine for a 2800 inverter.

I want to eventually switch the gas stove for a True Induction (would not run on inverter) and remove the propane tank to gain a compartment. So I would be all-electric (Have diesel Aqua-hot system). So I am leaning towards the MS2812 as it is only $200 more. Just have to see about DC wiring, just might call or write Newmar, maybe they oversized...

Algoma · 02-06-2015, 12:48 PM

I agree that you shouldn't have a problem on the AC side but in the all electric coaches Newmar add 4 more batteries and obviously beef up the DC cables for the extra input load. I think you will be lucky if they put heavier cables in without the extra batteries.

HHIDan · 02-06-2015, 01:05 PM

Quote:

Originally Posted by Algoma

I agree that you shouldn't have a problem on the AC side but in the all electric coaches Newmar add 4 more batteries and obviously beef up the DC cables for the extra input load. I think you will be lucky if they put heavier cables in without the extra batteries.

What inverter do they use in the all-electric with 8 batteries?

Mr_D · 02-06-2015, 01:19 PM

I'd go with the 2800 if I were doing it just to have the reserve if needed.

wa8yxm · 02-06-2015, 01:21 PM

First, I suspect 2,000 watts will still be eough but an upgrade (due to the additional draw of the fridge while microwaving) may be in order,, Be sure to add another pair of GC-2

As to the AC wireign (10=2 + ground) you have now) no changes needed, that cable is capable of passing 30 amps also the main circuit breaker remains the same, no changes on the 120 volt side need be made.. NOTE: if you wish to upgrade the 120 volt breaker (I see no reason to do so) then you need to change those wires.

On the 12 volt side, YOur likely have 4/0 wire (0000) I'd upgrade that a zero or two, you may also need a larger "T" fuse if you upgrade the inverter.. NOTE: I'd upgrade those wires even if you stick to 2000 watts (But not the fuse) Bigger 12 volt wires work better.

MRUSA14 · 02-06-2015, 01:42 PM

I'm curious where you got your prices. I searched for the MS2012 and all the prices I found were over $1700.

HHIDan · 02-06-2015, 01:44 PM

Quote:

Originally Posted by mrusa14

i'm curious where you got your prices. I searched for the ms2012 and all the prices i found were over $1700.

imarineusa.com

Scottybdivin · 02-06-2015, 02:10 PM

Quote:

I just finished replacing my Norcold for a Samsung RF18. I want to upgrade my Inverter to a True Sine Wave mostly as a precaution as everything seems to work fine (except my alarm clock).

That's going to be one expensive alarm clock.

The RF18 and everything else in the coach seems to be very happy on the ME3112.

HHIDan · 02-06-2015, 04:35 PM

Quote:

Originally Posted by Scottybdivin

That's going to be one expensive alarm clock.

The RF18 and everything else in the coach seems to be very happy on the ME3112.

My RF18 is not hooked up to an inverter outlet (will be as soon as I complete the exchange). I have tried it on ME2012 and yes I agree that it runs. I just don't know if a square wave is OK on my 4 new Sony TV's, microwave, RF18 etc, in the long run... (The alarm clock is indeed a nice bonus

)

And I also think 2000 watts is plenty, only going to a 2800 because it's about the same price.

Algoma · 02-06-2015, 04:52 PM

My previous coach had a MSW inverter and the TV worked fine. The microwave was not happy, but worked, and I did not have a residential fridge. From lots of other forums it seems the compressors are OK with MSW but the electronics have a problem. Actually MSW inverters are more efficient but given the choices I would still go for a true sine wave inverter.