akadeadeye Report post Posted July 16, 2010 Well, we are new RVers and have a new motorhome that has 50-amp service. We recently went camping with family at a state park and experienced our first 30-amp experience. I knew enough to only run one AC unit at a time and to watch the monitor when anything else was running and shut it off if the amp reading got too close to 30. We have a power management system and an Auto GenStart. At times, the generator would start, unexpectedly, when only one AC unit was running and nothing else. Once, we had a multitude of things running and it started and I very proudly explained about our power management system. But, after that, the gen would start without anything else running but one AC unit. It would also trip the breaker switch on the Onan 8000 gen unit, but not always. Could this be attributed to a drop in voltage at the shore power hookup? Any hints as to what was going on? We camped at a 50-amp site the following weekend and there were no problems at all. Don Share this post Link to post Share on other sites
wolfe10 Report post Posted July 16, 2010 Don, What was your voltage on shore power while running those heavy electrical loads? Brett Share this post Link to post Share on other sites
Guest BillAdams Report post Posted July 16, 2010 How are you reading the amps you are using? With 50 amp service you have 100 amps available (50 amps on each leg). With 30 amp service you have a total of 30 amps available from the 2 combined legs. Share this post Link to post Share on other sites
akadeadeye Report post Posted July 16, 2010 Brett, The shore power volt reading was 118-121, but it would change to 108-110, unpredictably, and at one point I thought I saw a reading below that. Bill, The reading on Line 1 versus Line 2 would be..........Line 1 -- 14 amps (occasionally spiking to 18 or 19) with the AC unit running. This was also the line with the refrigerator. Line 2 would read 0 amps. Don Share this post Link to post Share on other sites
akadeadeye Report post Posted July 16, 2010 I also tried running the AC unit which would be applicable to Line 2, thinking that 1/2 the 30 amp capacity would apply to 1/2 of my Line capacity (without the frig) which would mean the AC unit would be on one Line and the frig on the other, and still the generator would kick on. Don Share this post Link to post Share on other sites
wolfe10 Report post Posted July 16, 2010 Don, Even 20 amps continuous @110 VAC is just fine and at 108 is still acceptable. And on 30 amps, there is NO L1 vs L2-- in the 30 amp male to 50 amp female adapter, the single hot in the 30 amp is tied to BOTH L1 and L2 on the 50 amp end. Said another way, they are both on the same leg. And Bill is absolutely correct: RV math says 30 amp service provides 30 amps, 50 amp service provides 50 times 2=100 amps. Brett Share this post Link to post Share on other sites
eddie.leblanc@yahoo.com Report post Posted July 16, 2010 Not an answer to the questions, but there is a possible solution to many having to connect to a 30 Amp to power a 50 Amp line to the coach. Camco has a product that is a "Y" Adaptor that has a 30 Amp plug and a 15 Amp plug, feeding a 50 Amp female recepitacle. This will allow 45 Amps on the 50 Amp line to the Motorhome. It should be enough to feed most situations. The only caveat to its use is, it cannot be plugged into a GFI protected circuit. I've seen it advertised in several locations, and it is not extremely costly. Here is a listing on Amazon.com: Amazon listing: May be worth it if necessary. And many 30 amp park circuits also have a 15 Amp included. Ed LeBlanc '92 Beaver Grand Marquis "98 Honda Accord V6 EX Share this post Link to post Share on other sites
wolfe10 Report post Posted July 16, 2010 The device Ed is describing will work only in CG's that are NOT wired to code. Current electrical code (for many years) calls for the 15/20 amp ("regular") outlet to be GFI protected. If it is, the GFI will trip instantly with this device. Brett Share this post Link to post Share on other sites
smmlmm Report post Posted October 15, 2010 In a related question, my son in law rewired his home and put in a RV outlet outside--he told me it was 30 amp but because I have a 50 amp cord coming off my RV, he apparently put in a 50 amp receptacle (i can't ask him--he's in mountains of Colorado hunting-we are at his house with g-kids).... I hooked my progressive EMS before hooking up my shore power--got this reading leg 1 122 volts--60 amps---leg 2 no volts and no amps--I was afraid to hook up--question? Is this equivalent to 30 amp service? what about the 60 amp on leg 1? I only need power for my lights and refrig--staying in house-will NOT be running A/C or micro, etc....hooked up now with 15 amp heavy duty ext cord to regular home outlet... Can I hook my 50 amp cord to this outlet and let it run thru inverter or will it cause damage??? thanks for your advice. Mike (my coach '08 Fleetwood Revolution). Share this post Link to post Share on other sites
Guest BillAdams Report post Posted October 15, 2010 Do not hook up to that connection. You need to get a proper 30 amp plug installed with the proper grounds and proper power and neutral legs. Might it work? Yes. Are you willing to take that chance? I certainly would not. Share this post Link to post Share on other sites
wolfe10 Report post Posted October 15, 2010 Completely agree with Bill. For running charger and refrigerator, that HD 15 amp extension cord and proper adapters is a lot safer until you verify that the outlet is properly wired. 30 amp RV has one hot, one neutral and one ground. 50 amp RV has two hots (opposite legs of main breaker box so 240 VAC between the two hots), one neutral and one ground. Brett Share this post Link to post Share on other sites
