Best way to switch from shore power to inverter?

[Njmurvin]

I'm planning an upgrade to my solar capabilities which are quite minimal at the moment. Part of the plan is to use an inverter to power all the AC outlets when dry camping. I would probably be satisfied with a manual switch. But, 30 amp auto transfer boxes can be had pretty cheaply - so that's tempting. I just want to switch between shore and inverter power (disabling power to the converter/charger when in inverter mode). If I use a generator, I plan to use a portable and just treat it as shore power.

Is there a simple way to accomplish this?

[mbrower]

Impressive setup. Sounds like you have all the options covered.

Thank you. Spent a lot of hours drawing it out and finding parts that could handle the amps and would be reliable.

[Njmurvin]

mbrower wrote:
I installed a 2000watt inverter wired to an progressive dynamic transfer switch to power the whole RV. It automatically switches to inverter on loss of shore power and transfers back to shore power when available. I used a AC 4 contact relay to isolate both ACs, microwave, hot water heater, and battery charger when on inverter. I also have a 30 amp generator plug at the front of the rv that uses the inverter circuit through another transfer switch and another relay to power the RV along with one AC and battery charger but keeps the second AC and hot water heater isolated when using the generator. Everything works automatically and keeps all power sources isolated from one another as well as isolating high loads when using alternate power sources.

Shore power has priority over everything and generator has priority over inverter.

Impressive setup. Sounds like you have all the options covered.

[waltbennett]

ScottG wrote:

GrumpyandGrandma wrote:
If you get the right inverter it will have a built in transfer switch.

This is what I was thinking but I looked around on-line and couldn't find one. Maybe I wasn't using the correct vernacular? How do you identify these?

You've a fifth wheel with 50 amp shore power service, correct? Your power panel will be like mine - the 50 amp input is split into two 30 amp circuits. Most larger inverters have a transfer switch and sometimes more. The 4k inverter I got (price was only $850!)had a transfer switch AND solar charger (didn't need that as I already had a Morning Star).

I broke the input cable before the power panel and put my inverter/charger in one circuit. I moved the air conditioner, ref. AC and the converter/charger over to the straight one, leaving all the wall outlets, large TV and microwave on the inverter one so we could dry camp comfortably save for the air conditioner. (Your power panel's breakers are most likely alternating one breaker on one, the next on the other of these circuits.) If we need the AC, I run a genny. While the inverter would probably power the AC, I've only four T-105s, and they would only last a half hour at best. So far, we've only needed the genny a few times, so I can't see the expense of another four or more batteries and solar panels.

The system has worked flawlessly for over three years. Only issue we had was in CA two years back with daytime temps over 105 - even in the shade, electronics just does not like ambient temps over 100!

[jffnkrn]

For us: i have of course normal shore power, and a 3000 honda that are both tied in going through a transfer switch. Then on the inside just above my electrical panel is a 400 watt inverter. I have a basic connection at the inverter to run two receptacles powered only by the inverter. If i need to use 12 volt power converted to watch tv or use computer etc at table, i simply use the inverter powered receptacle and turn on the inverter. everything else is run through the normal house power supply. Generator takes care of things that need more power. For us that works well and is very inexpensive. I have all led lighting and two group 31 agms. Solar power for maintaining batteries, generator and of course food and beer. so for us, works great! Good Luck & Be Safe ! ! !

[mbrower]

I installed a 2000watt inverter wired to an progressive dynamic transfer switch to power the whole RV. It automatically switches to inverter on loss of shore power and transfers back to shore power when available. I used a AC 4 contact relay to isolate both ACs, microwave, hot water heater, and battery charger when on inverter. I also have a 30 amp generator plug at the front of the rv that uses the inverter circuit through another transfer switch and another relay to power the RV along with one AC and battery charger but keeps the second AC and hot water heater isolated when using the generator. Everything works automatically and keeps all power sources isolated from one another as well as isolating high loads when using alternate power sources.

Shore power has priority over everything and generator has priority over inverter.

[Jimf1234]

2oldman wrote:

Njmurvin wrote:
The more I think about it, a manual switching system may be best for my usage.

Works for me. I did hard-wire the DTV box to the inverter because manual switching will kill it, and it's 6+ minutes to reboot. Even a 'very fast' transfer switch isn't fast enough.

Another solution is to use an upsups to keep your direct tv box on while you switch power supplies.

[time2roll]

Njmurvin wrote:
I would not like these appliances to start using battery power just because I lost power at the pedestal.

Just leave the inverter off until needed. Push the button only when you need power.

[Veebyes]

I have a very nice, expensive, pure sine wave Magnum 2000w inverter/charger. Also have the remote control panel to go with it. It has the automatic transfer to inverter but I don't use it.

Much prefer to do it the manual way so that I do not find myself killing the battery bank in no time as the inverter tries to heat the water or run the fridge. It is a simple matter to turn the water heater, the fridge, the built in heaters & microwave circuit breakers off & turn the inverter on when wanted for the outlet circuits.

[Housted]

I have the auto transfer switch to go between the shore cord and the gen set. I plug the shore cord into the output from the inverter for whole house power. I came up with a circuit to disconnect the converter/charger from power when on inverter and automatically connect when on gen or shore power. all switching from one to the other is done from inside the 5er. A recent week at Death Valley with no hookups worked great. Ran the gen for microwave, coffee maker, and hair dryer otherwise all ran from inverter including TV and satellite system. I have 450 watts of solar which kept the batteries fully charged every day. 🙂

Housted

[2oldman]

Njmurvin wrote:
The more I think about it, a manual switching system may be best for my usage.

Works for me. I did hard-wire the DTV box to the inverter because manual switching will kill it, and it's 6+ minutes to reboot. Even a 'very fast' transfer switch isn't fast enough.

[Njmurvin]

Thanks for the great feedback everyone! The more I think about it, a manual switching system may be best for my usage. I think I would actually prefer not to have an auto switchover to inverter if shore power is lost. If I have hookups, I'll have the refer on auto/electric and possibly the water heater on electric. I would not like these appliances to start using battery power just because I lost power at the pedestal. I would rather be aware and in control of the switchover to inverter so I can adjust the loads accordingly. And if I'm dry camping (which is going to 99.99% of the use case for the inverter), it becomes a straightforward switch setting during setup.

[GordonThree]

ScottG wrote:

GrumpyandGrandma wrote:
If you get the right inverter it will have a built in transfer switch.

This is what I was thinking but I looked around on-line and couldn't find one. Maybe I wasn't using the correct vernacular? How do you identify these?

Tripp-Lite, Magnum, Xantrax to name a few...

[FLY_4_FUN]

I installed a Xantrex 2000W inverter and it will pass through power to a 15A circuit on shore power. The circuit I chose to invert was my tv/stereo etc but my fridge is on there also. I always switch to LP dry camping anyway so not a big issue. I had dreams of using my microwave but truthfully I can fire up my Honda 2000 in seconds if I want to reheat food....vs taking a full day to top up my batts with solar. I would like a full house setup but just not ready to do that extra work.

[time2roll]

http://www.donrowe.com/Inverters-with-Transfer-Switch-s/1937.htm