Good morning,
First, let me introduce myself. I’m a refugee from RORT on Usenet. I just joined this forum and this is my first post. I’m a retired nuclear engineer and electronic design engineer.
I just bought a new to me (‘05 model Tioga Walkabout) and as I did on my last rig, I’m equipping it with a large battery and charging system. My ultimate goal is to be able to spend quiet hours with an AC running from batteries. I’ll be chronicling this on my blog, http://www.johndearmond.com.
I don’t like the combined chargers/inverters for the simple reason that if one part fails, the whole unit is out of service. Therefore I am using a separate inverter and charger.
Batteries
AGMs are the way to go. Wet cells are so last century. I have some AGM traction batteries (100 amp-hours, over 100 lbs of lead.) from the old AVS electric bus company in Chattanooga. They’re over 10 years, yet they discharge test at about 90% of rated capacity. I’m probably not going to use these because they are so large for the amp-hours. I’m currently looking at this battery, specifically 5 of them:
https://www.batterystuff.com/batteries/ups-telecom/universal-12v-110-ah-deep-cycle-sealed-agm-battery-ub121100-d5751.html
I have experience with this battery. Though it is made by the chicoms, it is a quality product. I’m still shopping for a better price for that class of battery.
The Tioga layout is incredibly wasteful of space but by removing a panel and replacing it with a door, I’ve found room for 5 batteries. Conveniently, this compartment sits directly on a frame rail so no reinforcing is required.
The batteries should be inside the living spaces where they are protected from weather extremes. The LAST place for the house battery is under the hood - the way Tioga did it.
Cables
I use #2 welding cable for the battery to inverter wiring and #4 welding cable for the other connections.
Charging.
The rig has one of the old Magnetek 6300 charger/converters which outputs a screaming 5 amps of charging current. I’ve replaced the converter part with a Progressive Dynamics PD4655V 55 amp insert.
http://www.progressivedyn.com/pd4600_converter_replacement.html
This is a combination smart charger and 12 volt power supply to the rig.
Because my theory is that the batteries should be charged as fast as possible to minimize generator run time, I’ve also installed a PD 9280 80 amp converter that I had laying around from another project.
http://www.progressivedyn.com/rv_converter_pd9280_2.html
I’ve tested the two and they work well in parallel. That is a total of 135 amps of charging capacity.
Inverter.
If you need pure sine wave (I don’t), use one of the ProSine inverters from Xantrex. I’ve used the modified sine wave inverters that Harbor Freight sells for years with never a failure. This is the 2kW one that is going in my rig.
https://www.harborfreight.com/2000-watt-continuous4000-watt-peak-power-inverter-69662.html
It is on sale for $130 right now. I carry a Remington electric chain saw (about $40 from wallyworld). The two work together wonderfully. I live at the end of a 25 mile winding mountain road so I have to cut my way in or out fairly frequently.
Switching
I wanted the switching from shore power to generator to inverter to be automatic so I installed two Parallax ATX 301 (30 amp) automatic transfer switches. I give top priority to the generator, next priority to the inverter and finally last is shore power. The reasoning for this is simple. If I’m in a campground and the power becomes marginal, I want to be able to turn on the inverter or start the generator to override shore power. I want starting the generator to cause the generator to assume the load from the inverter. The wiring for this will be detailed in my blog as soon as I can get it posted.
Alternator
This rig is built on a Ford E350 van cut. It has a 100 amp alternator but as-received, it squealed the belt at full load. The solution is NAPA’s highest quality replacement serpentine belt. I’ve never found another belt to compare. I'm looking into higher capacity alternators but for now the stock one will do.
That’s about it for now. Questions are welcome.
John
