Unbalanced Electrical -- 127 volts and 116 volts?

[flbill]

Originally Posted by Road-Chi

The coach seems to be wired to create an unbalanced load. Almost everything we use routinely is on Line 2, such as the dryer, microwave, HVAC 1, HVAC 2, fireplace, toaster, and coffee maker. About the only things on Line 1 are the stove top, HVAC 3 (the back unit), and the dishwasher. Here is a picture with more load on Line 2.Attachment 387034

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I have not read all the posts, but as a former commercial electrician (apprentice and journeyman) it is not unusual to be wired unbalanced.
Your stove top (electric?) will use a ton when all burners are on. Your dishwasher will draw a ton when the motor starts. The AC also.

In homes, the wiring to the stove is literally undersized (legal by code). Why? Because you rarely use all the burners. But in an RV, use the stove, the dishwasher and the AC - and I am certain you will blow some fuse.

As for the other line - the toaster and coffee maker are likely outlets (minimal use). The dryer - will pull alot until to get started. Microwave is a short duration and the two AC's is the big one - and you want them basically alone.

To me - it all sounds pretty correct.

If you truly want to check things - turn everything on at full load, or turn everything off.

B

[Mark 7]

An organization I belong to has a campground that has been there for 30+ years. When power was run in, people had tent campers or small travel trailers and nobody had any A/C. There are probably 50 or 60 campers in and out of there now at any given time and all are fed with #2 Aluminum, literally 100's of feet to the last ped, and wire is protected at 60 Amp. Most peds have only a couple of 20A outlets in them (one on each phase), but a few have a 30A thrown in for good measure.

During the slow weekends, I will plug in to recharge my battery, but during a couple of peak weekends I have seen the voltage drop to as low as 95 V. Of course when this happens current goes off the charts... from time to time popping the 60A breaker feeding the whole mess. I have measured a 20 V difference between phases on many occasions. It all depends who is hooked up which phase and what they are running. It is a mess, and would never be found in a public camping area. I suspect the apparent voltage difference between phases in a real campground could be possible, unless each ped had a home run to a big distribution panel in the park somewhere. I suspect that may be a code requirement now, but I am not sure.

Mind you, this is NOT a regular campground open to the public. and cost to be in your spot is only $30 a year if you volunteer enough hours, but you use the electricity at your own risk.

Interesting read...

[Surf Fisher]

My advice is to forget the Vega Touch and install the Progressive Industires EMS-HW50C device prior to your transfer switch. Also install their A/B Switch which allows for two displays, one outside in your service bay that you can view once you hook up to shore power and one inside where you can view the performance of your incoming power without having to go outside.

https://www.progressiveindustries.net/ems-hw50c

[bobfrommaine]

RV manufacturers who install transfer switches are causing a lot of problems and this issue is representative of one of them. The transfer switch has screw terminals which clamp the wire(s) and these terminals are NOT large enough to capture a 6 AWG (BIG wire size) stranded wire. With that many strands, it is nearly impossible to get them all into a small terminal; so, many RV manufacturers try to insert the wire ends into a mold and then solder the wires to match the shape of the mold and the terminal. GREAT IDEA! Except over time, the solder starts to flow away from the points of greatest pressure and a resistive contact results. This little tiny resistance (one to 5 tenths of an ohm?) creates heat, the more current you try to draw, the higher the heat, and coincidentally, the higher the voltage drop. I've had 2 Class A RV's and both had this problem. Low voltage on one leg. The first I ended up selling, the 2nd caused a major melt-down inside the transfer switch and I needed to replace the switch.
Industry standards allow for "coining" the ends of stranded copper wire, but this method does require the use of special copper sleeves, crimping, and/or silver soldering. It is extremely (!!!!!) difficult to properly flow solder up a #6 AWG stranded copper wire using a soldering iron or a torch without damaging the insulation or making the wire brittle. Most transfer switches can accept stranded copper #6 wire as long as the manufacturer's torque specs are followed. My recommendation is to take the cover off your transfer switch (power and generator OFF, incoming wire disconnected) and checking the tightness of the screws on the various connectors. If they are loose, look for blackening of the insulation near the connection, if it is black, remove the wire, cut off the ends past the overheated part, re-insert the wire(s) carefully and tighten the screws per the manufacturer's specification. Undertorquing will cause problems as much as will overtorquing (distorts the connector socket), so a trip to Harbor Freight for a torque wrench that measures in inch/pounds may be helpful. My experience with some electricians is if they can continue to turn the screw and it doesn't come out the other side, it probably isn't tight enough. Not the right approach.

[rggarrott]

In 13 years of RV'ing, I've twice found pedestals with dead legs or bad breakers. I always plug in my surge suppressor and check the indicator lights before plugging in the coach.
On several occasions, I've had the high voltage alarm on the Vegatouch go off while connected to an RV park pedestal; once so unbalanced and causing enough concern I disconnected. In every case it happened during the early evening peak load period when the distribution system is stressed. At other times, voltage readings were in the normal range.