Xantrex inverter/charger installation I had a 1800 watt quasi-sine wave (modified sine wave) inverter in my Breakaway as original equipment. Although it was disconnected when I bought the Breakaway, I re-connected it and it served my purposes for 3+ years. I had an “extension cord” like system from the inverter to a 50 amp connecter in the shore power compartment so that when I was traveling and not plugged into shore power, the inverter would power all the AC requirements just as if I were plugged into shore power. The only downside was that I had to be very careful not to run the A/C units or the battery charger while the shore power plug was plugged into the inverter power. I forgot a few times and with the battery charger on, getting power from the inverter which was getting power from the batteries the battery charger was trying to charge, it didn’t take long and the batteries were DOWN! Wasn’t the answer to a perpetual motion machine! Other issues were if I was running the A/C with the generator, and if the generator quit, it would go back to shore power (inverter if on and the shore plug was plugged into the inverter) which would immediately overload the inverter. No damage was done but a burned trace on the A/C control board and a blown fuse, both of which were fixed and the A/C units were OK again. The microwave would run fine on the inverter but, the microwave power was way down, about 1/3 to 1/2 the normal power when plugged into real shore power or running off the generator. This is normal when microwaves are used with modified sine wave inverters and there is an explanation for this, later write-up. I have a 50 amp dual input system in the Breakaway so that limited the choice of inverters that I wanted to consider, the choice either Xantrex or Magnum Energy that offered dual AC input/output on their 3000 watt pure sine wave inverters. (Magnum Energy unit was rated at 2800 watts.) I could have used a 2000 watt unit but none had dual AC input/output configuration. A smart charger was also needed to replace the old Todd unit that was in the Breakaway, that unit was just a +12 volt power source @ 75 amps that would put out either 13.0 VDC or 14.12 VDC depending on a jumper selection. In the past, I would put it into the 14.1 VDC position and then manually switch to the 13.0VDC position to give the batteries a “2 stage charger” not nearly as good as today’s smart chargers would do but good enough that the batteries would not boil dry! Xentrex unit, the RS3000 soon became the first choice after reading the reviews and the performance capability. Main issue here was the size and weight of the unit. It is BIG 16” X 14” X 8” and HEAVY 75 lbs! The second issue was where to mount it! Xantrex recommends that the unit be located no more then 10’ from the battery, and at that length recommends 4/0 cable! As storage space is at a premium in the Breakaway and no available storage compartment is within 10’ of the batteries, the decision was to locate the unit in the same compartment where the old inverter and charger were located, at the foot of the bed. (That may have been a bad decision, the unit does generate a lot of heat when charging batteries and is noisy when the fans kick up to high speed, but we will have to deal with it.) To locate the unit there, many things had to be changed! The wiring in the compartment was a real mess, something I have wanted to address previously but now was a good reason to fix! There was a lot of extra wire that isn’t needed and was just folded up and stuffed into the area. The breaker panels (both AC and DC panels) were obviously fabricated outside of the coach during manufacture and then connected to the main coach wiring thru “quick connectors”. I really dislike those AC quick connectors used in RVs and try to replace them every chance I get. For the DC panel it was connected with a 3’ jumper set that was not needed, all it added were two connections, some voltage drop, and a mess! Same for the AC panel.

The first thing I did was to evaluate what was there, what needed to be removed and what needed to be re-worked. What I started with:

What a mess:

First I disconnected the inverter and removed it, then with the inverter out of the way, I removed the AC breaker panel, more mess:

That is all the wire that was attached to the AC breakers panel once the panel was removed it is clear how much extra wire was used. The connections from the body wiring and the breaker harness are visible and several of them, coffee maker and the microwave, showed signs of being over heated. Now that the breaker panel was out of the way, the transfer relay box was relocated further to the right in the area and righted so that is now sitting square with the cabinet!

Next I added the new AC breaker panel. The old one had to be replaced because it did not have the capability to split the loads upon entry so that the A/C units had their own breakers prior to the inverter and could not be loaded on to the inverter buss. I fabricated a new panel by using parts and pieces from two boxes.

The new breaker panel was located very close to the transfer relay panel and the cable to and from the transfer relay panel was shortened.

Wiring coach harness to the breaker panel:

Move the DC breaker panel next to the AC breaker panel:

To here:

The DC extension cable was removed but unfortunately, the spade connectors on the coach side were male and needed to be changed to female so they would then plug into the DC circuit breakers. Once again the coach wire was long enough to reach the new location of the DC breaker panel.

Wiring completed to the DC breaker panel.

I then completed all the ground connections (green wires) to the grounding strip that was also moved under the AC breaker panel.

At this point I made up a plywood mock up of the inverter/charger foot print just to make sure I was heading in the right direction.

With great effort I got the unit into place, Xantrex requires 3” clearance around all sides, this condition was met.

The unit was attached to the wall using 6, 5/16 bolts, The plywood wall is constructed of 2 pieces of ½ inch plywood and will be plenty strong enough to hold the 75 lb inverter.

The wiring from the AC breaker panel to the RS3000 was done. I used 6 gauge 4 conductor wiring as required.

The DC side of the inverter was also a challenge, the requirement for 4/0 wire, 350 amp fuse and cutout switch required some thought. I made up copper buss bars to connect the T105 batteries in parallel to provide a better connections then the battery posts. The battery posts only have a 5/16 bolt and while that is good enough for a pair of batteries, not good enough for 2 pairs to provide 350+ amps.

I added brass posts to the top of the battery posts to hold the buss bars:

Next was to fab a switch and fuse holder assembly.

This assembly was mounted on the wall just above the batteries and easy reach thru the access door.

A cover was added to protect the fuse and prevent accidental contact with HIGH DC current.

A large rubber hose will be added over the buss bars of the batteries to prevent accidental contact there as well, as of this writing it has not been done.

Next was to finish the job by adding the control panel to the area above the door, the alarm system has never worked so that was removed and another alarm consideration will be considered in the future.

The xantrex communicates between the RS3000 and the control panel via a Cat 5 or Cat 6 internet cable, although it is not a Unix format the cable and connectors found on a standard cable may be used. The issue here is getting the cable from above the door area back to the area at the foot of the bed. I attempted to remove the assembly above the door BUT that proved to be very difficult! I made an aluminum mockup of the size of the hole, the area of the panel and four mounting holes for a template. I carefully cut the vinyl ½ inch smaller then the actual cutout of the wood, that way it would be held in place by the panel once the panel was installed. During wood cutting, I pulled the vinyl under the mockup piece so that I had a clear area of wood exposed and wouldn’t damage the vinyl. I used a Fein saw which is a very nice gadget to have, it allows close cutting and because it uses a thin vibrating blade, very easy to cut along the mockup template. Other then a lot of dust, it went well. Once the opening was cut to the proper size the control panel was connected to a 25 foot length of Cat 6 cable.. Xantrex control panel has two RJ45 sockets and there is a terminator that must be installed in the unused socket.

Routing the cable was a bit of a hassle, I was able to get the cable into the refer area at the back and down under the floor, from there went back along side of the wheel well and back under the raised area in the bed room, finally snaked into the electrical compartment, plugged into the RS3000 and again with the terminator in the remaining RJ45 socket. All that remained was to carefully cut an opening for cool air to be drawn into the inverter. A metal grill will be made later.

Comments: I retained the Todd power source and connected it so that if I have shore power, or if the generator is running, I can power the coach DC system from it. It will charge the batteries (backup to the Xantrex unit) if the batteries are on line (controlled by the Big Boy main contactor) The main reason is if the Xantrex is asked to de-sulfate the batteries, the batteries must be taken off line as the high voltage pulses used to de-sulfate the batteries “may” damage other electrical components. With the Todd unit running, I can power up the coach DC systems and the Xantrex unit will de-sulfate the batteries off line. I would also have a back up incase anything went wrong with the Xantrex unit. Concerns: Mounting the unit inside at the foot of the bed may have been a mistake but I really had not choice. Heat from the unit is alot, much more then I expected from a unit that supposedly has such high efficiency. Noise from the fans, while not bad when first starting, gets quite load after the unit has been on for awhile and operating under load conditions, primarily battery charging. Will be monitoring it on the next trip to see if it really a concern or not, some noise absorption techniques may have to be considered as well as an extra low speed/low noise fan to remove heat from the compartment.

Ed Raether 07-17-09