Forum Discussion
59 Replies
- crawfordExplorerit people could read and see the interlock system it is safe and legal and yes you can back feed by turning off main and locking it out you can legally do it. I been doing it for years and never a problem.
- stugpanzerExplorerIt's one of my options. I also have a Harbor Freight 8k screamer and my favorite a military surplus MEP803A 10KW diesel GENNY!
- 2manytoyzExplorer II
JaxDad wrote:
2manytoyz wrote:
I've not done this yet, but it is planned soon. I'm going to add a 240V outlet on the RV, near the generator.
Your 5500 Onan genny has a 240 output?
Mine only has a 120 volt output.
Upon researching this project, unfortunately it doesn't. It has two 120VAC circuits, but that doesn't create a 240VAC (L1 & L2) like a home setup.
I could add a 30A 120VAC outlet instead, and power up one leg of my house power. I may still do this, but it's far less desirable than what I had intended.
I already have a Yamaha EF2400iS that can accomplish this same task without modification. I also have a 7500W Champion dual fuel generator which will supply 240VAC to run all my dedicated circuits via the transfer switch.
For now, I'm going to put this RV project on a back burner. - rgatijnet1Explorer IIISince we live in a hurricane prone area we have used the RV to power the house refrig and freezer. The last time we did this the power was off for four days and we just lived in the RV, with the AC, during that time. Our house refrig and freezer are both energy efficient appliances so they do not use much power from the generator to keep them running. I also wired several 12 volt LED lights throughout our house that are powered by a 12 volt auto battery. This allows lighting throughout the entire house whenever we needed to use the house bathrooms. We are on municipal water so our bathrooms remained functional. I used those LED lights extensively for four days and the single 12 volt battery still seemed to have a full charge.
By living in the RV we had cool AC, satellite TV, WIFI, microwave, and stove. Basically all of the same comforts of our RV at an RV park. By preparing for the power outage in advance, we had plenty of fuel for several weeks, if needed.
I see no need to install a transfer switch when the ONLY items in the house that I need to power are our refrig and freezer, which can easily be powered with an extension cord. Doing it this way also meant that we did not have to haul things out of our house and put them in the RV refrig and freezer. We kept our RV refrig off, which saved fuel. Anything we needed was only a few steps away in the house. - DrewEExplorer II
wvabeer wrote:
Gundog wrote:
Please don't. Use a transfer switch designed for this application do not trust your main breaker as a disconnect to the utility. I am a retired journeyman lineman and this can kill utility workers. I can't tell you how many failed main breakers I have seen.
Would it be legal if I installed a 200 amp disconnect between the meter and main panel? Back feeding would be so much easier.
It would (likely) be legal to install the master disconnect. It would not be legal or safe to backfeed without without a proper transfer switch even with such a disconnect.
The basic requirement is simple: you need an approved system that makes it impossible to connect the two power sources together by design, not something that relies only on following some connection procedure properly. There are approved setups based on mechanically interlocked circuit breakers, some of which may be installed in some existing electric panels (certain panel makes and models). Unlike Gundog, I am not aware of many failures of circuit breakers to disconnect when shut off, excepting a couple well-known problematic designs that should be replaced if found...most notably the Federal Pacific Stab-loc ones that have a very high failure rate and have caused many fires. I have heard of problems caused by people backfeeding and not disconnecting the main properly, be it because of ignorance or forgetfulness or whatever.
Backfeeding also practically always involves some sort of suicide cord or other dangerous connector arrangement that can have expised live pins.
Use an approved transfer switch (or plug stuff into extrnsion cords etc. completely separate from the house system). It is the only acceptable and safe method. - wvabeerExplorer
Gundog wrote:
wvabeer wrote:
I was hoping to back feed my house thru the shore power cord by killing the main power flip a switch in the motor home (separate transfer switch) and run a few items till power is restored. Maybe ad a twist lock at two points within the transfer switch, one at incoming power and other main gen power connecting to the cord depending which mode I'll be in.
Please don't. Use a transfer switch designed for this application do not trust your main breaker as a disconnect to the utility. I am a retired journeyman lineman and this can kill utility workers. I can't tell you how many failed main breakers I have seen.
If you back feed into the utility the 120/240 volt service feeding your house comes from a transformer that converts primary high voltage at the transformer to the 120/240 volts for your house. If you back feed into the transformer you create primary high voltage through the transformer. The transformer is a simple device feed high voltage in the top it makes secondary voltage out the bottom feeding your house feed secondary voltage into the transformer and it makes high primary voltage out.
Not just utility workers are at risk lets say you have a wire down on your street or 2 streets over and you back feed through your service and the neighbor kid moves the wire so he can play and dies or is maimed guess who is at fault or maybe the downed line starts a house fire etc. I know of one lineman personally that got killed by an illegal hooked up generator in Mariposa, CA and their have been more many more.
It doe not matter if your home is fed underground or overhead the threat is the same.
Best case scenario is the utility worker grounds the primary line and smokes your generator. Do NOT TRUST YOUR MAIN BREAKER TO BE A DISCONNECT TO THE UTILITY. A proper transfer switch is a break before make device that gives a physical separation to the utility service.
Would it be legal if I installed a 200 amp disconnect between the meter and main panel? Back feeding would be so much easier. - JaxDadExplorer III
2manytoyz wrote:
I've not done this yet, but it is planned soon. I'm going to add a 240V outlet on the RV, near the generator.
Your 5500 Onan genny has a 240 output?
Mine only has a 120 volt output. - turbojimmyExplorer
2manytoyz wrote:
I've already added a 10-Circuit 30 Amp Manual Transfer Switch Kit from Reliance Controls to our house.
That's the one I installed, too.
I didn't use metal conduit for the 10 ga wire that runs to the inlet box like you did. Not sure if it's required by code - all of the other wiring in and out of my main panel is exposed as installed by the electrician when the house was built.
I, too, will eventually put a 240V outlet in my generator (6.5 NH series) compartment so I can plug it into the house. My NG/propane portable generator works great, but it can't hurt to have a gasoline backup. - JaxDadExplorer III
2manytoyz wrote:
I've not done this yet, but it is planned soon. I'm going to add a 240V outlet on the RV, near the generator.
Your 5500 Onan genny has a 240 output?
Mine only has a 120 volt output. - 2manytoyzExplorer III've not done this yet, but it is planned soon. I'm going to add a 240V outlet on the RV, near the generator.
We live in hurricane prone FL, and outages are frequent enough to warrant the effort.
I've already added a 10-Circuit 30 Amp Manual Transfer Switch Kit from Reliance Controls to our house. The kit included a 10 foot generator cord and outdoor plugin box. Cord would be too short to reach the RV outlet, but I've already purchased a 50' power cord rated at 7500W (RV generator is only 5500W).
https://amzn.to/2R997ky
Here are the details of my installation:
http://www.2manytoyz.com/manualtransfersw.html
https://amzn.to/2rK37As
This will be an easy modification to the RV. I like that the onboard generator has about 60 gallons of available fuel before the 25% cut-off feature comes into play. I'll primarily use this at night, when I don't want to have to refill the portable generator fuel tank in the middle of the night.
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