Solve Driveway Camping GFI Problems by Splitting the Neutral

An RV of decent size expects a 4 slot, 50 amp power cable which provides two 50 amp circuits.  When driveway camping, most hosts don’t have a 50 amp power connection, so if two circuits are desired (for running two air conditioners, for example) a splitter like this can be used along with a 30 amp to 20 amp adapter to present two 20 amp plugs that can be plugged into two different circuits in the house:

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The problem is that most household outdoor plugs have a GFCI in the circuit that looks like this:

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The GFCI protects homeowners from shock by insuring that the same amount of current flows back into the neutral return wire as flowed out from the hot wire.  If not, it means some of that current is flowing elsewhere, like through a person.  When this current imbalance is detected, the GFCI “trips”, and needs to be reset.

Since the RV power system has in its four connector jack two hot lines but only one neutral, using the splitter above won’t work if either 20 amp plug is connected to a GFCI-protected circuit, since the current returning from the two hot lines spills into a common neutral, and is then split by the splitter.  Since the current has been “mixed” on the common neutral, the returning current on the then-split neutral will never exactly match the inbound current from the corresponding hot line, so the GFCI will trip.  It’s like two parallel rivers: the inflow and outflow on a given river is identical, but if a trench is cut to connect the two rivers, the inflow and outflow on each river won’t match since one river donated a bit of its inflow to the other river’s outflow through the trench.

The solution is to split the neutral, so that each of the RV’s two circuits is completely separated from the other.  Here’s the common, single neutral bar in the RV’s breaker box:

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I removed the neutral bar and installed two separate neutral bars:

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Since the neutral from the RV’s four pin connector now only serves the right side of the breaker box, I brought an extension cord in, cut off the female end, and wired it in on the left side of the breaker box to supply power for the left side.  I did the same thing on the right side too, so the right side can receive power from the big 50 amp connector on the back of the RV or through its new 20 amp extension cord.  The right side can also receive power from the inverter I wired in a while back, so the three breakers that can provide power have been colored to insure I only turn one on at a time.  I also added a second meter so I can repay our hosts for the power used on both circuits:

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The new pair of 20 amp power cords come out through the bottom of a compartment.  In the plastic tub they’re plugged into a pair of extension cords that lead to the house:

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Until now, the common neutral problem has limited us to one 20 amp circuit when driveway camping, which can be uncomfortable in hot weather since an RV this large needs both air conditioners to keep it cool.  I’m happy to have finally broken free of this limitation!

Day 599: Installing the New Oven

Shabbos was just a bit on the hot side of comfortable, with highs in the high 80s.  We had lunch with Rabbi and Mrs. H and their children, which is always a pleasure!

Today we moved back to my parents’ house from the synagogue.  This will use up the last 24 hours of the 72 hours per month we’re allowed to be parked in front of their house, so tomorrow we will have to move on.

Today’s project was to replace the RV range with a residential range.  Our current oven is about the size of a microwave oven, and Trish could really use more space for cooking more elaborate Shabbos and holiday meals.  Here’s what we started with:

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The first step was to remove the range:

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Next I removed the cabinetry and countertop around the range, leaving a 34” wide alcove for the new range:

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Next I added an outlet for the residential range and modified the propane plumbing to attach to the new range while preserving the quick release propane connector for our catalytic heater

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After replacing the natural gas orifices in the cooktop and making a few other adjustments in the oven, the new range was ready to run on propane instead of natural gas.  After attaching the propane line and plugging into the new outlet, the new range is ready to go:

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The only down side is that the oven seems to keep the 400-watt electric igniter on whenever the oven is heating (as opposed to turning off once the gas is ignited), so we will have to be careful not to use the oven for several hours when the solar system isn’t charging the battery.

Day 596: Las Vegas Urban RVing, Day 1

Today promises to be a normal weather day here in Las Vegas, which is about ten degrees hotter than Cottonwood.  So long as we keep the slides in, the neighborhood watch doesn’t bother us:

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We are considering replacing our 3 burner, 1ish cubic foot RV range with a four burner, 5 cubic foot residential gas range.  This would involve tearing out cabinetry, adding electrical service behind the range, and modifying the range to run on propane rather than natural gas.  We visited a few stores to see what’s available in black and stainless:

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Trish has been wanting to replace the RV sofa with a living room set that takes up less space.  This set has ottomans that come out from under the chairs.  L’Chaim!

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Bubbe and Zayde took us out to dinner at Sababa’s.  I’m not sure what’s going on here:

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On the way home we purchased the furniture set and set it up where the sofa used to be:

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Day 589: 12 Gallons of Water Found Hiding in RV

No doubt so our RV manufacturer could save money by using lighter duty suspension components, our RV only has a 45 gallon fresh water tank, which is on the small side for an RV of this size.  Most RVs used by fulltimers have at least 100 gallons of fresh water on board.  In turns out to not be that big of a deal for us, as we can last about 5 days on 45 gallons of water, and we tend to go out on trips or to do errands frequently enough that we fill up our 45 gallon water bag in the bed of our pickup and bring the water back to the RV. A few times, though, we’ve run out of water and have been forced to make a special trip just to get more water.

Water in the RV is pumped from the fresh water tank into the plumbing to create water pressure at the sink and shower.  Cold water is also pumped into the 12 gallon water heater.  The pressure on the cold side pushes the heated water out of the water heater into the hot water lines.  When there’s no more water in the fresh water tank, hot water no longer gets pushed out of the water heater, so it just sits there.

I realized we could use this 12 gallons of water heater water if we could access it.  I removed the anode rod from the tank and added a T fitting which allowed me to screw the anode rod back into the T fitting and install a garden hose attachment on the side:

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I then attached the other end of the hose to the fresh water fill attachment on the RV, and set the fill mode to “winterize”, which uses the onboard pump to draw from the fill attachment, not from the fresh water tank.  This is normally used to draw anti-freeze into the RV’s plumbing for winter storage, but in this case I’m sucking water out of the water heater and making it available for use!  We now have 12 gallons of water we can use in a pinch if we empty our fresh water tank.

For this to work, I have to open the pressure valve at the top of the water heater so that air can enter the tank to replace the water removed.  I installed a screen over the valve to prevent bugs from crawling into the water heater through the vent.  I also installed a screen between the hose and the RV pump so that any scale or other particles from the water heater aren’t ingested by the pump.

Just for fun, we lived on water heater water for the whole day!  

This afternoon, B and I went for a ride “around the block”.  Much of the Forest Service road was quite rough, and we passed a dead rattlesnake on the road!  At one point, there were cows all over the road, which made B nervous, so I rode ahead and encouraged them to move along.

Day 501: Battery Charger Rewire

We had a nice Day 500 Shabbos in Las Vegas! Last night we had a Chanukah party with our parents, which was nice.

Today I tried to salvage the staircase the was damaged in Alaska by cutting off the bottom-most stair. This allowed me to at least get the staircase to unfold, but after 30 minutes of sledgehammer lovin’, I still couldn’t get the staircase back to a shape that would allow me to mount it back on the RV, so I gave up on it.

The RV’s battery charger, which is powered by our generator on those rare occasions when we strike out with solar, is wired with 6 gauge wire, and is about 20 feet from the battery, which I believe adds enough of a voltage drop (1.19 volts according to the math) to dramatically reduce the ability of the charger to actually charge the battery. I moved the battery charger about 2 feet by wire away from the battery, and used much thicker 2 gauge wire. Voltage drop should now be 0.047 volts. The charger is the silver box in the photo:

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Tomorrow I’ll break out the A/C plug for the charger so it pops out near the propane quick release for the generator. This will save me from having to run an extension cord from the generator all the way to the chassis A/C input on the rear of the RV, like I’ve been doing so far.

This had been on the todo list for months, so I’m happy to finally get to it.

While I was rewiring the RV, Trish went boot shopping with Grandma DiAnn. Sounds like they had a lot of fun!

Tonight we’re overnighting at Camping World, as we have to do a couple more errands in town tomorrow before we can head out to Jean Lake.