Update on our 2012 IB....Still investigating the solar installation. My coach is one of a few in 2012 which was not pre-wired for solar. I spoke to the tech at the factory and got some great hints to run the wiring. I've pretty much nailed down the stuff I'll be using. I'll do a photo story on the installation...
The photo story is not yet ready, but the fast and dirty review of my solar installation:
My 2012 was manufactured just before they began to pre-wire for solar. I'm glad, because I suspect the factory, in pre-wiring for their smaller panels, uses lighter wire than I used, and probably didn't provide for controller wiring in the location I chose.
I installed 2 Kyocera 140W PV Panels on the roof behind the Air Conditioner using StickyFeet mounts (3m VHB). I wired them in series in order to reduce the amps going to the charge controller, and to get maximum effect from the MPPT controller. I get a shadow on one of the panels about 2 hours before sundown if facing due West, or until 2 hours after sunup if facing due East. If I had wired the panels in parallel the shadow would affect only one panel. There is no shadow during the peak the charging hours, so I decided the shadow in the weakest current production hiurs would be tolerable, and wiring in series would outweigh that disadvantage. So far, I'm OK with my decision.
I ran the 10 AWG wires down the plumbing vent in the driver's side rear corner, into the large rear storage unit; the distance was only about 8 feet. I did not use a junction box on the roof, but placed the fuse, junction box, and kill switch high on the rear wall of the storage compartment. From the junction box, I ran 8 AWG wire under the coach to the small basement compartment just forward of the entrance door and just aft of the passenger door. I chose that compartment because my coach has the entertainment center option in the compartment just aft of the entrance door, which is where many folks have located their electronics, and I also have a Nanostation Wifi antenna and a wireless router in that compartment, running on the inverter/120-powered outlet.
I was aiming for a reasonable cost in this installation, so I chose to risk a Chinese MPPT charge controller as an experiment. It's a Tracer 2315 30 Amp controller from Amazon, which has received fairly good reviews and may be considered the best of the Chinese controllers. It doesn't have as many bells and whistles as the MorningStar 45 amp MPPT controller, but the unit and remote display were about 1/3 the cost. After two weeks of testing, it's performing better than my expectations. If it fails, I'll replace it with the new MorningStar 30 amp controller just being introduced. In that same compartment I also mounted a kill switch between the controller and batteries.
The installation instructions recommended 6 inches of ventilation above and below the controller. The compartment is only 14 inches tall and the controller is almost 10 inches tall. They also recommended a positive air flow (fan) in a compartment with little ventilation. I made a mounting frame from aluminum angle, mounted the controller away from the side wall with lots of space behind it (where the cooling fins are located), and mounted a 12V cooling fan on the frame, aimed at the cooling fins. I found a 12V thermal switch that comes on at 100 degrees and shuts off at 85 degrees and wired that inline, along with LED indicators that report power to the thermal switch and fan "on", since I can't see the fan. I powered the fan directly from the batteries. In two weeks of hot Florida operation the controller has remained cool and the fan has never come on.
The controller is just 4 feet from the batteries, but I used 6 AWG wire to minimize voltage drop. The controller converts the nominal 24V input (actual up to 34V) at just under 8 amps to nominal 12V (actual up to 14.8, depending on which of the 4 stages in which the controller is operating) at up to 15.8 amps, although the highest real-world amperage I've seen so far is 14.2 amps. I have a Trimetric battery monitor measuring volts and amps both in and out of the batteries, and the charge controller's remote showing volts and amps out of the controller. The difference in amperage represents the load at any given time.
It took me about a week to install everything, working just a few hours each day (I'm 73 years old, and no longer need to drive myself to exhaustion). I'm afraid of ladders and heights, so I did have a younger (and braver) friend do the panel installation on the roof. Total cost, including the panels, panel mounts, controller and remote, wiring, loom, fuse holders and fuses, kill switches, junction boxes, fan and thermal switch, etc was around $1,200; add in the Trimetric meter I bought prior to the solar purchase in order to measure current loads and the total is closer to $1,400. I'm not looking for a return on investment; the installation is strictly for convenience.
The coach is going to be parked at JFK airport in NYC for about a month while we take a NY-London cruise then an Amsterdam-Basel river cruise; my goal is to provide at least enough power to keep the fridge and phantom current draws running. That draw is a little less than 2 amps per hour, or about 48 amps per day. I've had it running for about two weeks in Florida sunshine (with some cloudy and/or rainy days) with those current draws plus the fantastic vent fan and the inverter powering the wireless router, totaling about 5 amps 24 hours/day, and the system has been keeping up beautifully, batteries full as early as Noon. When we get to National Park boondocking, I expect to be able to keep the fridge going 24/7 and normal evening use, firing up the generator only for microwave/toaster oven, etc.
We park the van like that once or twice per year, usually to take cruises from distant ports; in 2012 we parked in Vancouver while flying to Anchorage and cruising back to Vancouver (that was in our Free Spirit, and we threw out all our fridge stuff and turned off the power while we were gone), and in 2013 we parked in Pittsburgh while taking an Ohio River steamboat cruise.
The batteries are the weak spot at the moment, they are the standard Interstate Group 27 12V batteries under the step, supplied by the factory. They are Marine deep cell with dual deep cell/cranking abilities, not true deep cells. They're not rated in amp hours, and the best I can determine is they are about 85 to 90 amp hours each. They're nearly new, however, and I'll wait until I get some use out of them before I replace them with some serious battery power.
The roof of this 24IB is now crowded, with antennas (3), skylights (2), vent fans (2), air conditioner and two PV panels 60" x 26" each. Good thing I have no intention of mounting a satellite dish up there
:.