Inverter Installation, Hurricane Style?

[AlwaysDreaming]

I just bought a Thor Chateau 22FT RV. It does not have an inverter (DC to AC power). Therefore, I don’t have AC Power while cruising unless I fire up the generator. I would like to watch TV, use Medical Equipment, power computers etc., make a (K-Cup) Coffee while cruising, all low power AC requirements, without using the noisy Onan on-board gas AC generator. Also, when shore power is not available, I need very low AC power capability overnight for a CPAP (medical equipment) and I don’t want to use the gas generator.

2 House batteries (1 comes standard) with an inverter solves these problems. Quiet AC Power. 1 12V House Battery and a 1000W Pine sine wave Inverter will cost me $400 to $500.

Here is a DIY installation I am looking for comments and opinions on.
Permanently mount the Inverter and connect DC to the House Battery Bank (which is attached to the engine alternator (70 AMP DC)). Back feed (plug the converter output into a AC outlet) the AC to one of the AC Outlets using a modified AC cord called a suicide cord because it has a male plug on both ends. Before connecting, switch OFF the Main AC Breaker, switch OFF the Converter Breaker, switch OFF the Air Conditioner Breaker, switch OFF the Microwave Breaker. This gives me low power AC throughout the coach.

Does anybody see an electrical problem with this, other than it is not idiot proof? That is, you have to remember to switch OFF the respective AC Breakers. I would rather not blow up the coach to find out I overlooked something obvious.

This will give me about 10 amps of AC power without the on-board AC generator (the on-board generator pumps out 30 amps). While cruising, the Ford Triton V10 Alternator pumps out 70 amps DC so I have enough DC power to convert to AC power. When “Dry Camping” I can run the CPAP 8 hours since it only draws 25 watts, without drawing down the batteries too much.

This is essentially what I do at home when hurricanes blow through and we lose power to the house. I have a 7000 watt 240V gas generator. I have a suicide cord and back feed through the electric dryer plug. Of course, I switch off the Main breaker from the transmission line to the house, and the AC, stove, water heater, etc. since I only have 30 amps of 240VAC. It is enough to survive in South Florida. Hence, the post title of Hurricane Style. Maybe I should have called it suicide style?

[jayw900]

You could make a suicide plug but only you know if you're smart enough to use it intelligently. I wouldn't recommend it.

[westend]

I'd suggest to abandon any suicide cord use, especially at your residence but also at your RV. At your house, where does the neutral phase power connect to when powering your generator through the receptacle? In your RV, there is no ground to earth until either a shore power cord is used or until a separate ground circuit is installed. This makes the use of a suicide cord even deadlier.

[Ron3rd]

2oldman wrote:

CA Traveler wrote:
Turn off the converter and plug the main RV power cord into the inverter.

x2

I believe he has a motor home not a trailer

[DrewE]

AlwaysDreaming wrote:

2112 wrote:

AlwaysDreaming wrote:

CA Traveler wrote:
Turn off the converter and plug the main RV power cord into the inverter.

I don't think that works while you are cruising

Why would this not work?

This would work, but it takes more installation. The inverter is on the opposite side of the coach where the batteries are. Would I run the cord under the coach and drill up into the shore power box?

You will have an easier time if you put the inverter as close to the batteries as possible and run an AC power cord to wherever you need it. If your shore power cord stores in a compartment (rather than being, say, a detachable cord with a connector mounted on the outside wall), you may be able to install a receptacle in the cord storage compartment wired to the inverter and plug the shore power cord in there while it's stowed for travel.

For a 1 kW draw on the inverter, the DC cables are carrying somewhere in the vicinity of 100 amps. That requires quite heavy wiring to minimize the voltage drop over any reasonably long distance. (It also requires pretty heavy wire regardless of distance for safety's sake, to avoid overloading the wiring and potentially starting a fire.)

[CA_Traveler]

If your AC pedestal cord or other cord has to be routed outside the rig then that is a cruising consideration but it works fine when parked.

How you route a cord from the inverter to the pedestal cord is dependent upon your rig. But if under the rig for driving then it needs to be protected.

[AlwaysDreaming]

2112 wrote:

AlwaysDreaming wrote:

CA Traveler wrote:
Turn off the converter and plug the main RV power cord into the inverter.

I don't think that works while you are cruising

Why would this not work?

This would work, but it takes more installation. The inverter is on the opposite side of the coach where the batteries are. Would I run the cord under the coach and drill up into the shore power box?

[AlwaysDreaming]

The problem is that the coach isn't wired for 12 VDC outlets, if there is such a thing. 110V VAC outlets are wired throughout the coach. Are you suggesting I run a cord from the cigarette lighter in the cab to the bedroom in the back? AC is a much better transmission line system, ask Tesla about that.

[2112]

AlwaysDreaming wrote:

CA Traveler wrote:
Turn off the converter and plug the main RV power cord into the inverter.

I don't think that works while you are cruising

Why would this not work?

[keymastr]

Your C-PAP is already 12 volts. The brick in the 110 cord converts the 110 to 12 volt. All you need id a 12 volt adapter which you can buy from your CPAP supplier. Plenty of 12 volt TVs on the market for less than $200 also and plenty of 12 volt coffee makers too.

The only thing you need a generator for these days is the microwave or air conditioner. And for those I wish more folks would get an inverter generator like the Hondas that are super quiet. No need to run those loud fuel guzzlers anymore.

[MrWizard]

K cup coffee maker the 'Hotel' model wait for the water to get hot, single cup of water reservoir
uses about 600w
the full size model uses 1100-1500w depending on brand and model

plugging the shore cord into the inverter is lot better much safer idea than a back feeding suicide cord

pulling 50 - 120 amps using these devices is best done with a larger battery bank,
don't expect your avg alternator to be able to handle this
the alternator will max out and not be able to do it
the batteries supply the majority of power the alternator adds a little extra
then recharges what was used from the batteries

[AllegroD]

time2roll wrote:

AllegroD wrote:
Please get rid of the suicide cord!! You do not need it. You can use a Male Leviton Outlet.

That is an inlet and still needs a transfer switch for isolation.

Yes. It does. OP needs to do research on that or interlock.

Sorry for not saying that.

[GordonThree]

You can hear your on-board generator running while driving? I would think road noise and the main engine would make enough noise to equal the small generator.

[ScottG]

Please don't build a suicide plug.
There are reasons some things aren't done. You may think you have everything covered and then the one thing you didn't think of actually does happen and someone gets hurt or yes, even killed. Don't mess with the odds.
If your going to do this job, do it right.

[rockylarson]

Get a CPAP machine that runs off of 12volt.