That makes total sense, Mike, and I think I will be doing the same. We live in an old house and are constantly aware of how many things we have operating on some of our ‘weaker’ circuits, so power awareness is something we already do. If I am able to power the refer, watch TV and then fire up the microwave for a couple of minutes I will be happy. I’ll need to check the specs on these items and make sure that will work. As always, thanks so much for generously sharing your knowledge!

Congratulations on the new coach Bruce! I originally wanted the MS2812 also, but the wiring requirements for it are heftier. You can download the owners manual and take a look. At the time my wiring run was around 8 feet, which would have required two runs of 4/0 cable between the inverter and the batteries (instead of one run for the MS2012). At $10 per foot, that’s an extra $160 (8 extra feet of black and red) of 4/0 cable. Also the MS2012 can “surge” to support 2800 watts for up to five minutes, which was all we should need (e.g. run the toaster oven for a few minutes). The MS2012 is 13 lbs. lighter (minor but I keep track of these things). And with our 4 lead acid batteries, we really shouldn’t be drawing more than 2000 watts very often or for very long. When boondocking we just need to be careful not to, for example, run the toaster oven and microwave at the same time, or we may trip a breaker. But if we did run both we’d end up draining our batteries really quickly anyway. Hope this helps!

Just got my new coach and a new inverter is first on the list of improvements, along with solar panels. I’m trying to decide between the MS2000 and MS2800 and thought I would check with you to see why you went with the 2000 watt unit vs. higher power. I’ve read that you lose some efficiency with higher output inverters, so if 2000 watt does the job, I suppose there is no reason to go higher. I value your input.

Bruce

Congrats on the 32SA! A king bed is one thing we miss in the 36LA (and we notice it since our dog always sleeps on the bed with us!).

I measured the battery compartment at 10” wide x 29” long x 11” high. It’s easy to fit 400 Ah of Lithium in there. I think I’ve figured out a way to fit 500 Ah in there but it would be tight and would require arranging the cells in a non-standard way. The other thing I’ve considered is installing Lithium cells indoors somewhere, like in the cabinet under the computer workstation dinette. Since that’s in the slide-out, I’m not sure if the cabling would be feasible though. Now that we’ve done a fair bit of boondocking this year, I think I’d be comfortable with just 400 Ah of Lithium, knowing that the generator and Magnum inverter will recharge them much faster than the lead acid batteries, and that I can use much more of their capacity (say 70-80% instead of 40-50%). If you do get Lithium, I’d love to hear about it! I’d like to do a DIY Lithium install since buying cells on eBay seems so much cheaper than from someplace like AM Solar. -Mike

Another great installation and detailed write-up. My 32SA is being built as I write this and I’ve learned so much from your blog that I feel I owe you and Kathie some beers and dinner if our paths ever cross on the road.

A solar upgrade is 1st on my list when I get my new coach and my system will look pretty much like yours, plus I am going with lithium batteries right away. My question is…do you know offhand the dimensions of the battery box in the stairwell? I’m reasonably certain 400AmpHrs will fit, but 600 would be great. I know that lithium is probably in your future, too, so I figured you would have it figured out.

Thanks, again.

It depends on who you ask. Personally I think it’s OK, as do many other RVers, especially since cell phone and laptop chargers usually have their own power transformer built in (the “brick” that plugs into the wall or is found halfway along the power cord). Many RVs come with modified sine inverters (like ours did) and I think if lots of cell phones and laptops were being damaged we would have heard a lot more about it by now. Some people claim modified sine is always bad, and some claim pure sine is usually a waste of money. No simple answers…