I just installed a Magnum inverter in our 2004 Monaco Signature. I had previously installed a Magnum inverter in our Windsor and it was easy compared to this. The Signature install had some challenges, so I thought would post the issues and how to resolve them (most of them).
Note: I just realized this is going to be a very long post, but I think it’s necessary to include the details.
Original Inverter- Trace RV3012GS with RC7 remote. This is a 3000 watt square wave inverter with built in AGS and a Solar connection.
New Inverter- Magnum MSH3012M Hybrid with ME-ARC50 Remote and ME-AGS-N auto gen start (AGS). This is a 3000 watt pure sine wave hybrid inverter (it will supplement shore power when necessary).
There was nothing wrong with our Trace inverter, but I had a Magnum pure sine wave inverter on my long term upgrade list. A pure sine wave inverter is better for fine electronics and residential refrigerators. Having previously owned a Magnum inverter in both our Windsor and Executive, I really like the menu and the battery charging features over the Trace plus the pure sine wave output. Forum member 4x4 installed an awesome solar system and his relatively new Magnum inverter came up excess so I purchased this inverter from him. If you are purchasing a new inverter, either West Marine or Tekris Power has great pricing.
Monaco uses a slide in bracket and 2 screws to mount the Trace inverter to the basement ceiling. The issue is the
Magnum inverter mount flange is thicker than the Trace and it is also slightly narrower (13.2”w for the Trace and 12.625”w for the Magnum) and the Magnum inverter will not fit into the original bracket. Monaco welds a long piece of angle iron to each side of the large steel cross members so the inverter can slide into place (see picture). I had to use a die grinder with a cutoff wheel to remove one side of the angle steel bracket and then pry down the other side so the thicker Magnum inverter flange could slide into place. I used a small floor jack with a board on it to hold the Magnum inverter in place against the ceiling cross member. I then drilled and installed eight #10 self-tapping screws. Make sure you leave enough room behind the inverter for air to circulate. The manual says 3” on the sides and 6” front and back.
The next issue is the Trace inverter has a
large grounding lug on the side and the Magnum does not have this. This is the main battery ground for the house batteries. A large 4/0 ground cable is routed from the Trace inverter to a ground stud on the main frame rail. You have a choice. You can run a new ground cable to the Magnum inverter front stud where the battery negative wire also attaches (but then the plastic cover will not fit) or there are two battery connection studs (pos and neg) about 2 feet away on the front of the basement compartment next to the frame rail. The original Monaco ground wire was too short, so I purchased a 4’ piece of 4/0 cable and soldered new ½” copper lugs to it. I ran the new ground from the compartment stud to the main frame ground stud. Just a side note, without this ground cable there is no 12v house power. It took me an hour and some help from forum member K7JV to figure out why I had no house 12v power! I had to temporarily use a car jumper cable until I could make up the new ground cable.
The next issue is the wiring. This is a multifaceted problem! The Trace has a built in Auto Gen Start (AGS), dual 30A 110v inputs- (one on one leg, and one on the other), and a solar interface. (See Trace and Magnum wire connections pictures).
If you require Auto Gen start, the Magnum inverter uses a small add on accessory for Auto Gen start (ME-AGS-N). See picture. I installed the Magnum AGS to the basement ceiling next to the Magnum inverter. The Magnum AGS will start the generator based on your inputs for battery state or coach inside temperature. Some of the wires from the Trace inverter will go to the Magnum AGS, but you are missing a
generator run sense wire. This wire tells the AGS that the generator is running. After almost a week of searching, I located this wire on the older Ridgecreek temperature AGS unit near the old Trace inverter. A side note: The old Ridgecreek Temperature AGS looks almost identical to the Magnum. Even the input wire terminal numbering is identical! Gen run sense is on terminal 2 on both units. Turns out one of the Magnum founders designed the Ridgecreek AGS. The Magnum AGS also needs a +12v wire from the batteries so it knows the battery voltage. This is easily run from the positive 12v battery input lug on the front of the inverter to the AGS (include a 5a fuse in this wire). See attached PDF for detailed wiring color code from Trace to Magnum AGS.
There’s more! The Magnum AGS can utilize a house temperature input for Auto Temp Gen Start, but you will have to route the Temp cable up into the coach. This Temp sensor comes with the Magnum AGS. I’m going to route the Temp sensor from the basement up under the refrigerator where the propane line runs and then up along side the refrigerator compartment. I plan to drill a small hole in the wall next to the fridge and secure the temp sensor in the wall. I purchased one of the small white Dometic AC Temp sensor covers that I will place over the Magnum temp sensor.
The MSH3012 only has a
single AC input up to 60 amps (this is so it can monitor input power and supplement it if necessary). The coach is wired with two 30 amp 10 gauge 110v wires (out of phase) from the shore power panel. Do not connect these together from the original breaker locations! With help from K7JV, I was able to relocate circuit breakers to the same phase and use two parallel 30 amp 110v AC input wires (same phase) to the inverter AC input. Be careful to balance the loads when you do this (example is two Air Conditioner units on one leg and one Air Conditioner unit and the inverter on the other). Hindsight: An easy way to avoid this issue is to purchase a slightly less expensive Magnum MS2812 inverter. It also uses two 110V AC inputs and is a pure sine wave inverter.
My Trace inverter has a single small gauge +12V red wire connected to the
Solar Pos terminal. It had nothing connected to the Solar Neg terminal. I have not been able to track down the function of this wire and it’s not in the Trace manual. My guess is it tells the Trace inverter when the solar system is charging the batteries. I have not connected this wire to the Magnum inverter and taped it off. If anyone has more knowledge or ideas, I’m wide open because even the Xantrex-Trace tech guy didn’t know!
Both the Trace and the Magnum battery Temp sensors (BTS) use RJ11 telephone cord, but the Magnum uses a
different resistance sensor. If you connect the Trace BTS to the Magnum inverter it tells the Magnum that your batteries are over 300 degrees F. Not good! You can just disconnect it. Running a new wire from the center basement compartment to the batteries is a job! It may be possible to cut the Trace temp sensor off in the battery compartment and connect the Magnum sensor (it will require figuring out wire polarity). A better alternative is to install a Magnum Battery Monitor System (ME-BMK). It uses a shunt to give you a true representation of how much DC power you have used.
Next is the remote control. I used the ME-ARC Magnum remote (you can recognize it by the Favorites menu). See picture. You can also use the slightly less expensive ME-RC50. Both Trace and Magnum use an RJ11 phone cord for communications from the inverter to the remote. But,
Magnum reverses the plug polarity on one end! I’m not sure why, but Dometic does the same thing. You must cut one of your original Trace RJ11 cable ends off and install a new plug with the wires reversed. This requires an RJ11 crimp tool and new connector. Most RJ45 internet crimp tools will also work on RJ11. The Magnum remote is also wider than but not as tall as the Trace.
The Trace remote panel cutout is 4 1/8” wide x 4 ¼” tall. The Magnum ME-ARC remote cutout is 5” wide x 3” tall. I widened the hole ¾” with a jig saw and found a piece of cherry ply wood and cutout a small filler piece. I made the piece slightly larger than the hole and then filed it to a snug fit and glued it into place on the top of the hole. Then drill new holes and screw it down.
If I was doing this again, I think it would take ¼ the time and effort and I would use a Magnum MS2812 inverter. I sure hope this write-up helps you guys.
I’d like to thank forum member K7JVand Magnum Tech Glenn Darby for all their help on this project.
Pictures:
1. Trace inverter slide in mount
2. Trace wire connections
3. Magnum wire connections
4. ME-AGS
5. Ridgecreek temp AGS
6. ME-ARC remote
Also attached is a PDF with AGS wiring details.
Linear Mode
