Magnum Energy, the rest of the story.


So, Magnum Energy products, by Magnum Dimensions, are the makers of our inverter chargers and related components. Let’s make life a little easier for the typist:

  • I/C = Inverter Charger
  • RC = Remote Control
  • BMK = Battery Monitoring Kit
  • AGS = Automatic Generator Start
  • VDC = Volts DC
  • SOC = State of Charge (Percentage that the batteries are full)

NOTE: In this context when I say batteries I am talking about the HOUSE batteries.

Our coaches come with an I/C. Most of them 2000W on the inverter side, pre mid 2017 a modified sine, usually the ME-2012, after mid 2017 the pure sine MS-2012. I upgraded my ME-2012 to a MSH3012M for the only reason of having a few more watts and getting pure sine. It does more than I needed, but it was on sale. Read about the upgrade here.

Since somewhere in the early-mid 2000’s (still pinning this down) the remote upstairs was the ME-RC50. Those coaches also came with the AGS.

I added the BMK, the reasons and process described in detail here.

I highly suggest you read the two mods linked to above before you continue. Because now the plot thickens. We’ve been having extensive discussions on social media (10 RV owners 12 opinions) about what VDC to have the AGS start the generator. If you have now read the BMK upgrade post you will understand why I am always complaining about the fact that it is a very poor parameter to do that by VDC. My reasoning is that with the BMK installed the AGS should be able to use SOC a MUCH more accurate indicator.

Why? Voltage is an indicator of SOC for a bank that is AT REST. (30-60 minutes, room temp). If your bank is 80% it’s, in theory sitting at 12.45 or so VDC. Now the fridge comes on. What happens? Voltage drops. 12.2, 12.1….. is SOC suddenly 50%? No. But, we want the AGS to do its thing when the bank is 50% and then charge to 80%. How long does that take? Again, voltage is no help. So what do you set your voltage? You guess. Consensus is that when voltage hits 12VDC (which will happen with a draw, most likely the fridge) it’s about, maybe, sort of, 50%. Then run it for 3 hours. Bank is 450Ah, you’re at maybe 50%=225Ah needed to FULL. Running the generator in float charge is a waste of fuel, so let’s go to 80% SOC, 360Ah, so you need 360Ah-225Ah is 135Ah. Starts at 80A charge, drops down quickly to 40A-ish. So average say 50A….. 3 hours…… sort of. Anyway, waaaaaaay too inaccurate. Again, SOC from the BMK would be MUCH better.

So I called Magnum Energy. It turns out that it is possible. But, and that’s a HUGE but, you need certain equipment. Turns out that as they develop I/C’s and accessories they upgrade the capabilities. There are versions upon versions. And you need to have compatible versions to do what we want to do. So, how do you know what you have? You go HERE. There you will find compatibility charts….. I/C’s come in 4 levels. Which one do you have? Go to your remote and hit TECH….. turn the knob until you get to REVISIONS. Rotate to scroll through. There it is….everything you have.

So in my case the MSH-3012M is version 1.6 The chart says version 1.1 or higher is level 4. Cool. (Turns out even a level 1 will do what we want to do with the right RC) Now the bad news, my RC is the ME-RC50 Rev. 2.8 Down below the compatibility charts there are links to the various remotes and their capability. Here’s the ME-RC50. It shows that AGS programmability is VDC and Temp only. That’s it, no SOC. Now, go look at the ME-ARC version 3.0/3.01 or version 2.3/2.4 There you see that AGS programmability DOES include AGS setup based on SOC (start/stop) BINGO! Slide over to the right and, amazingly, you only need a level 1 I/C to make it work, although note 7 indicates you do need the BMK. But we already knew that. And the AGS needs to be version 5.0 or better.

Sooooo……. it appears that if I replace my ME-RC50 with an ME-ARC (Either version) I can in fact let my generator come alive at 50% SOC and run until 80% SOC. Sweet!

And the last question is of course, what does it take to upgrade? Apparently the hole in the wall is the same so it’s a matter of 4 screws and a cable. Cost? $2-300 One more tip, you can easily tell which RC you have by looking at the five buttons along the bottom. If the left 2 are “SHORE…AGS…..etc” you have the RC50 If they are “FAVS….CTRL…..etc” you have the RC-ARC50 (the added “A” being for “Advanced”)……. More here on the Magnum pages.

And, while we’re looking at these things there’s a whole lot of additional features at the more advanced levels. It’s gonna take me a while to figure it all out.

To be continued.