30-Amp Power Mystery

[jesfl45]

 

I have a mystery power problem. And, I really hope someone can offer an idea for a solution. I am at my knowledge's end.

My old, now-dead 30-amp "shore power" twist-on plug (on my power cord) overheated (again). I discovered it probably was partly because the connectors on the RV side (female) receptacle actually only make contact with 1/2 (or less) of the plug prongs. Learned my lesson. Ordered and installed a high-quality (expensive, comparatively) power connection (SmartPlug). Good engineering design. High quality. Perfect plug-to-receptacle connections.

Yet, for a mysterious reason, after the installation, I am not getting power to my transfer switch and power panel. It was working fine before the old power cord plug overheated. (My mistake was running the AC and the water heater on electricity simultaneously. I know better. I just forgot the water heater was on.)

What's especially strange to me is this:

(1) My multimeter checks show proper power out of the RV park's shore power pedestal, through my surge protector, to and through the new SmartPlug, and even to the RV connection end of the incoming wire. (I have pix of all the tests and connections, and I am confident they are all correct.)

(2) Yet, there is no power through the transfer switch to the 120-volt power panel. I have wired and re-wired several times to check myself.

(3) Therefore, thinking it might be a problem with the original through-the-floor 30-amp power line to the transfer switch in my 18-year-old RV (mice, or something), I bypassed the old in-floor wiring with a temporary connection from the power pedestal/SmartPlug directly to the transfer switch. When testing, the power is at the connection point in the transfer switch but not through to the 120-volt power panel.

(4) Here's why it is such a mystery to me. As a further test, I disconnected my temporary main power line. Then I connected the main power cable from my 3000W inverter in my solar system to the exact same main power line connection in the transfer switch. Everything works perfectly on inverter power. Right now I am running this computer, TV, lights, charger, outlets, etc. through the transfer switch and power panel with NO PROBLEM whatsoever.

Several times, I have disconnected the inverter power line and connected/tested the power pedestal temporary wire. No go.

Sorry for the length of this explanation. Thought it might be helpful. I'm no electrical pro, but I do know my way around my system and my multimeter.

This is likely some simple or basic problem that just eludes my knowledge level. I certainly will appreciate any diagnosis and suggestions for solving the mystery.

(Note: The good news is I've been running off my recently upgraded solar system for a week while dealing with this problem. The solar system is working beyond my expectations in Florida where there is plenty of sunshine right now.)

I would like to get the shore power working again, however.

Thanks in advance for any help anyone can offer. It will be very much appreciated.

jesfl45

[Kirk W]

First let me say welcome to the forums! We are happy to have you here and we will do all that we are able to help.

First I want to be sure that I am understanding just what happened and what has been done so far. If I understand correctly, your RV came with one of the shore power cords that is removable for storage and used one of the twist lock connectors similar to the one in the first picture. And if I am understanding, you have now replaced it with one like the second.

              

It isn't unusual for any of the commonly used electrical connectors to become warn and weathered over time and so to introduce resistance into the connection and current passing though any resistance will create heat. More current and/or resistance the more heat is generated and in time those connections fail if not replaced. 

Assuming that I'm looking at the instructions for the kit above, I really do not see anything difficult or unusual in the instructions and they would seem to be quite good. Based on my 40 years of electrical service work it is generally a good idea to very closely examine all parts of the work just completed if something that worked previously no longer works after the job is finished. I am wondering if it might be possible that the damaged or melted plug that you replaced was either not the problem that actually failed but perhaps just about to fail but something else failed first?  You should be able to measure resistance from each of the terminals on your transfer device all of the way back to the pins on the very end of your cord where it plugs into the shore power outlet. I would pull the plug around close to the transfer device to make those checks as there should be near 0Ω and certainly less than 5Ω. If you find anything significant I would certainly look to eliminate that. Have you traced the entire circuit from the transfer device to the plug on the side of the RV, visually to look for any signs of wear or of having been hot? If you fed the inverter through the transfer device via the terminals where your shore power cord connects, that pretty well eliminates everything from that point on. If you find something between the terminals and the end of the cord then next thing is to remove the power cord and test between the ends at the transfer device and the pins of the new plug on the side of the RV. 

Edited February 13, 2022 by Kirk W

[jesfl45]

Kirk, 

Wow! Thank you so much for taking the time to respond. I don't have your electrical experience, but  I think I've covered almost everything you've mentioned. However, I'm going to go through your helpful message again in the morning when I'm fresh and check everything point-by-point.

The most confounding thing to me is that I've got power from my solar system inverter through both sides of the transfer switch. I test-wired both sides with the main solar inverter power cable to check whether the transfer switch was the problem. Inverter power, no problem. Using it right now. Power pedestal power, nothing.  

Yes, I guess something could have been damaged in the transfer switch from the previous overheating. I assume if something was damaged in the 2006-vintage transfer switch (a fairly simple mechanism, it seems to me) either both -- shore power or inverter power -- or neither would work?

So, I'll take your points one-by-one and work through everything again tomorrow. It's a great roadmap for me. I suspect there is something -- probably simple -- I'm missing. And, I'll be able to employ a new, better multimeter I bought late this afternoon. My old multimeter was very basic and very worn.

Thank you so very much for your time and helpful thoughts.

jesfl45

[oldjohnt]

Good evening Jes, I will address your issues one at a time, hang on here goes

 POST 1 Yet, for a mysterious reason, after the installation, I am not getting power to my transfer switch and power panel. It was working fine before the old power cord plug overheated.

Response:

 You FIRST have to have “adequate proper power” at least getting TO the Transfer Switch and then ifffffffffff its working properly it passes through the OUTPUT to the main AC distribution panel. So when plugged to shore power,

(A)  WHAT IS THE VOLTAGE ON THE TRANSFER SWITCH INPUT ???????????????

(B)   WHAT IS THE VOLTAGE ON THE TRANSFER SWITCH OUTPUT TO THE PANEL ??

(C) WHAT IS THE VOLTAGE AT THE PANEL ITSELF ?????

 Perhaps when the cord overheated the problem is as simple as one of its conductors was damaged !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! CHECK THAT FIRST (continuity and resistance) to save all that below

POST 2 Yet, there is no power through the transfer switch to the 120-volt power panel. I have wired and re-wired several times to check myself.

Response:

  If there’s no power THROUGH but there is “adequate proper power” at the switches INPUT, the switch isn’t functioning properly orrrrrrrrrrrr theres a bad/resistive/loose connection

 POST 3

  I bypassed the old in-floor wiring with a temporary connection from the power pedestal/SmartPlug directly to the transfer switch. When testing, the power is at the connection point in the transfer switch but not through to the 120-volt power panel.

Response:

 Iffffffffffff that were truly the case ???? and there is indeed “adequate proper power” at the Transfer Switch I

NPUT (is there ???) but NOT at the OUTPUT to the Panel AGAIN THAT WOULD BE THE SWITCH ISNT TRANSFERRING THE POWER OR A BAD CONNECTION

POST 4

Then I connected the main power cable from my 3000W inverter in my solar system to the exact same main power line connection in the transfer switch. Everything works perfectly on inverter power.

Response:

If you have ”adequate proper power” at the same INPUT side of the transfer switch and now all works THAT SAYS THE TRANSFER SWITCH IS WORKING OKAY  

POST 5  Several times, I have disconnected the inverter power line and connected/tested the power pedestal temporary wire. No go

Response:  That says the switch is working so when connected to shore power THEREIN LIES THE PROBLEM,  shore power,,,,,,,,,, or pedestal,,,,,,,,,,, or the overheated cord,,,,,,,,,,,,or a bad connection..

(Note: The good news is I've been running off my recently upgraded solar system for a week while dealing with this problem. The solar system is working beyond my expectations in Florida where there is plenty of sunshine right now.)

I would like to get the shore power working again, however.

ANALYSIS

 Even with good plugs and receptacles is sounds like when connected to shore power YOU ARE NOT GETTING “ADEQUATE PROPER POWER” TO THE TRANSFER SWITCHES INPUT. This could be caused by

1)    A break or bad/loose/resistive conductor within the power cord, you have to ohm all conductors to look for a problem MAYBE A WIRE IS BROKEN OR RESISTIVE !!!!!!!!!!!

2)    A bad or loose or resistive connection in any of the plugs or receptacles

3)   If allllllllllll the connections and alllllllllll the plugs and receptacles and terminals are proper THE PROBLEM MUST BE IN THE CORD OR CONDUCTORS Maybe when it overheated !!!!!!!!!!!!!!!

NOTICE 1) If theres a bad loose resistive connection or a conductor at NO LOAD theres no V = I x R Voltage Drop  IE just because all voltages test okay at no or low load DOES NOT MEAN THERES STIL NOT A PROBLEM in a connection or a conductor or elsewhere YOU HAVE TO TEST FOR VOLTAGE UNDER A LOAD when any bad/loose/resistive cord or connection drops the voltage.

If allllllll works well with the Inverter feeding the transfer switch but NOT when connected to shore power, the switch must be okay and the problem is in the cord or plugs or connections FROM the Pedestal TO the transfer switch. If you rig a known good cord and connection FROM the pedestal TO the switch and all works YOU HAVE ISOLATED THE PROBLEM.   

NOTICE 2)  If the pedestal has a loose/resistive connection you could still see good voltage there  but NOT “adequate proper power” under load MAYBE THE PROBLEM IS AT THE PEDESTAL TO BEGIN WITH ??? and your cord and plugs and receptacles are okay hmmmmmmmmmmmmmm  

DISCLAIMER Im NOT any solar expert but an Electrical Engineer (late practice was AC Power Distribution) of over 50 years and I would begin with checking the integrity (continuity plus resistance) of all cords and conductors,,,,,,,,,all plugs and receptacles,,,,,,,,,,,then voltages UNDER LOAD in which case a bad/loose/resistive connection causes a V = I x R Voltage Drop. If all those new plugs are good and proper and it works with Inverter feeding the transfer   (AT SAME POINT AS SHORE POWER) Id suspect a cord or conductor as the problem WHEN IT OVERHEATED ????

NOTICE 3 ) Im going by you’re hooking the Inverter AT SAME PLACE AS SHORE POWER CORD such that the transfer switch itself is okay HOWEVER I don’t know your transfer arrangement or scheme and if its different let me know

Bad Pedestal,,,,,,,,,,,,Bad cord/conductors,,,,,,,,,Bad/loose/resistive connection are my guesses get your ohm and volt meter and trace it all out AND LET US KNOW. I have seen a ton of bad resistive pedestal receptacles CHECK THAT OUT UNDER LOAD to see voltage !!!!!!!!!!!

The Transfer switch could still be problematic ???????? but if it works when the Inverter feeds the same exact place as shore power DOES IT ??? ARE YOU HOOKED TO THE SAME PLACE ??? but NOT hooked to pedestal power that says the switch is okay………

Hope this helps, let us know I bet its simple like a bad wire or cord or connection or theres a problem in the pedestal ???????

John T  To long retired EE and rusty so no warranty

 

Edited February 13, 2022 by oldjohnt

[Kirk W]

11 hours ago, jesfl45 said:

The most confounding thing to me is that I've got power from my solar system inverter through both sides of the transfer switch. I test-wired both sides with the main solar inverter power cable to check whether the transfer switch was the problem. Inverter power, no problem. Using it right now. Power pedestal power, nothing.

This reply leaves me wondering if I am completely understanding what is happening there. What I think of for the "transfer switch" is something that we here usually refer to as the ATS or automatic transfer switch and it is actually a relay type of device. There are several makes & models around but basically they typically have 2 inputs, one from the generator and the other from the shore power cord. The device then has one output that feeds 120V power to the power distribution panel and its circuit breakers. In typical configurations it has a solenoid that receives power from the generator side that will transfer the power source from the shore power cord to the generator output if it is running. In the typical configuration the solar & its inverter would not use any part of the ATS, but would be a separate power source. 

Edited February 13, 2022 by Kirk W

[Kirk W]

I just saw a link to How an ATS works on another RV forum and you may find the article helpful. 

[oldjohnt]

The above kindly posted by Kirk is how I (absent his system diagram so I cant know) imagined and explained the OP and his transfer switch. My analysis and answer is based on the TS having TWO INPUTS    A) Shore Power         B Genset Power        and ONE OUTPUT that feeds the main AC distribution panel. 

 Its my understanding if he uses and substitutes INVERTER power (instead of shore power) on the A Shore Power INPUT side of the TS all works fine (tells me the TS is working) HOWEVER   if its actually Shore Power used on the A Shore Power Input of the TS via the Pedestal and Cord and Plugs and Receptacles it DOES NOT WORK  Is that your case?????

IF SO THAT TELLS ME THE SHORE POWER IS THE PROBLEM be it the pedestal or cord or his EMS or Surge Protector or a bad connection.

YET ANOTHER CONSIDERATION. If the OP has a transfer method that chooses between A Shore Power or B Inverter Power and feeds one or the other via the output to the AC panel  THATS A DIFFERENT BALL GAME. If he has that and all works on Inverter power but NOT shore power AND THE SHORE POWER AND PEDESTAL AND CORD AND CONNECTORS ARE ALLLLLLLLL GOOD       THEN ITS A TRANSFER SWITCH PROBLEM 

ALSO Ive seen even different transfer methods and even two switches and sub panels etc SO ITS HARD TO SAY FROM HERE HIS PROBLEM

Jes, if your transfer is as Kirk and I imagined work through my analysis as posted above to find the problem HOWEVER if its a different transfer system LET ME KNOW and I will post a different troubleshooting and analysis..

Does your TS select Shore or Genset orrrrrrrrrr Shore or Inverter or Shore and ?? A TS that selects between two inputs be it Shore versus Inverter orrrrrrrrrrr Genset IS BASICALLY THE SAME THING, TWO Inputs and ONE Output 

Check easy simple things first like continuity and resistance and the cords conductors and plugs and receptacles and insure there’s good power at the pedestal LET ME KNOW and post back any questions. It would be so easy if all you had was a bad cord !!!!!!!!!!! lol

John T

[jesfl45]

Kirk:

First, I owe you an apology because I failed -- in my exhausted state last night -- to say thank you for your gracious welcome to this forum.

I’m fairly new to Escapees, now nearing 2 years. I’ve met numerous Escapees members around the country who have been extraordinarily helpful. And, I said last night, you’ve gone above and beyond with your time already with your response to my mystery power problem.

Second, I didn’t mean for you to spend all of that time spelling out the possibilities. It was my intent do do much more testing per your first message and get back to you after that. What can I ever do to repay you for your extraordinary assistance? It is so very much appreciated.

Third, I just read for the first time today’s long analysis/diagnosis message from you. Again, I am overwhelmed with your effort and thoughtfulness. I need to read it another time or two and absorb point-by-point. I will do that again tomorrow morning when I am fresh again. Shortly, I’ll relax and turn my attention to the Superbowl.

Here’s the funny thing (or not so funny, from my perspective). I spent more than 6 hours today first testing everything as you suggested in you first message. I made may notes for you as I was going alone. I write a lot to help me think things through thoroughly and to document what I’m doing.

I’m not going to go through all of my notes tonight and send them to you. But, here’s the summary:

-- all of the testing and tracking had me open the power panel and test all the way through the transfer switch and all of the wiring to the main 30 amp breaker input connection. In every instance, I read 120+ volts at the input to that beaker -- from both the shore power connection and from my solar inverter connection.

-- Mysteriously, however, the solar inverter powers the entire RV system just fine. The shore power connection does not power the RV’s electrical system, even though I can read the 120 volts at the 30 amp breaker connection in the power panel. I do not understand that at all.

-- With my limited electrical knowledge, the only variable I could figure was the grounding from/in the old power pedestal. But, I do not have enough knowledge to figure how or why that would be the case? The solar system is directly grounded to the RV chassis and completely separate from the 120 volt electrical system until the connection at the A-B switch and then to-and-through the power panel. Interestingly, the built-in 3600 kw Cummins/Onan genset (one reason why I bought this older RV) is also grounded directly to the RV chassis.

(Note: no, neither the solar system nor the built-in genset connect through the shore power plug. I re-wired those separately into the transfer switch with an A-B battery-type switch like I used to use on boats in my sailing days. I had an extra one and that was an easy solution. Since I haven’t used the genset since I completed my solar system a couple of months ago, that A-B switch is permanently locked to the “B,” or solar system input.)

-- So my conclusion today is that the problem IS likely something in the shore power system, possibly something to do with the grounding (since grounding is the only variable I see)? It is a very, very old pedestal at this very old RV park where I am staying, which is owned and run by the city.

I don’t really know how to check the pedestal further (until I read your message from today again and again) in the morning. And, I’m sure not going to unscrew and open the city’s old pedestal box and take a look at the wiring inside. It is a 50 amp ONLY pedestal with NO BREAKER. I do have a surge protector plugged into the 50 amp power source through my 50-30 amp dogbone, and then to my shore power cord.

-- As I came to the conclusion the pedestal and grounding therein could very well be the problem (before I read your detailed information), I also realized that IF there is a grounding or other problem in the old pedestal’s wiring, that also likely would have contributed to the overheating and burn-up of the old shore power twist-lock plug.

-- My plan, as I sat down this afternoon to write back to you, was to ask about the appropriate tests to find the likely pedestal power problem. However, I am sure you’ve covered that in your previous message, so I’ll reread and absorb your points tomorrow morning and do whatever additional pedestal power testing after daylight tomorrow.

Please, please, don’t spend any more of your time until I get through the next steps in my testing.

I’ll let you know tomorrow whatever I find.

For now, I’m again running just fine from my 700 Ah of LiFePO4 batteries . . .and I’m looking forward to enjoying the game.

Thank you, thank you, thank you!!!  I’ll never be able to say that enough.

Jim Stiner (jesfl45)

[oldjohnt]

  Jim, thanks so much for the updated and detailed information, the more you can provide the better chances we have of helping you. Before I go through all your updates I sense you don’t understand the concepts of 1) “Grounding”,,,,,,,,,,,, 2) The purpose of the GrounDED Conductor (White Neutral) ,,,,,,,,,,,,,,3) The purpose of the Equipment  GroundING Conductor (Bare/Green),,,,,,,,,,,,,,,4) Bonding versus Grounding,,,,,,,,,,,,,5) Neutral and Ground are NOT the same. 6) N and G are bonded at the parks main BUT NEVER AGAIN DOWNSTREAM like in the RV panel.

NOTE the Grounded Conductor Neutral is to carry the normal return current while the EGC is ONLY to carry fault current YET THERES STILL 120 VAC LINE TO GROUND  and maybe due to a mix up or improper grounding or bonding or an open Neutral (coupled with other simultaneous faults or heat caused shorts) you’re reading 120 VAC but its NOT Line to true N !!!!!!!!!

FYI 1 In the RV’s main AC panel (unlike the parks main panel, its actually treated as a SUB Panel) the Equipment GroundING Buss is separated and electrically insulated and isolated from the Neutral Buss, the two ARE NOT BONDED TOGETHER. The Ground Buss issssssssssss connected to the RV frame

FYI 2 HOWEVER, in the RV parks distribution system the Neutral Buss and Equipment GroundING Buss ARE BONDED TOGETHER.

FYI 3 If alls well since N and G are bonded in the parks dist system there would be 120 VAC from Line to EITHER N or G……..If Grounding and Bonding were incorrect or mixed n matched and/or the Neutral were open (coupled with other simultaneous faults or heat caused shorts) the 120 VAC shore power you’re reading at the panel could be the 120 VAC Line to Ground yet there’s no 120 Line to Neutral !!!!!!!!!! If the Neutral got burned open during overheating but the Ground was intact you could read 120 VAC Line to Ground subject to the Grounding and Bonding and incorrect or open or shorted conditions.

FYI 4  It gets more complicated with an Inverter or Genset because they create their own N G Bond and that connection is also tied to the frame of the RV. If that’s not configured properly you could end up with multiple NG Bonds while an open N while you can read 120 VAC yet things NOT work

FYI 5 Even if the Neutral were burned open (like could have happened when a cord overheated) there could still be 120 VAC from Line to Ground subject to certain conditions. In addition to possible NG shorts caused by overheating

 TESTING VOLTAGES AT THE 50 AMP PEDESTAL AND QUESTIONS FOR YOU

If alls well there should be 120 VAC from EITHER L1 or L2 to Neutral as well as 120 VAC from EITHER L1 or L2 to Ground………There should be 240 VAC from L1 to L2   IS THERE ???????????

If you have a 50 amp to 30 amp dogbone adapter there should be 120 VAC from L to EITHER Neutral or Ground   IS THERE ????????????

 NOW LET ME WORK THROUGH YOUR UPDATES

1)      You state:  “all of the testing and tracking had me open the power panel and test all the way through the transfer switch and all of the wiring to the main 30 amp breaker input connection. In every instance, I read 120+ volts at the input to that beaker -- from both the shore power connection and from my solar inverter connection.”

 MY THOUGHTS If the voltage is correct there yet the Inverter causes the RV to function but NOT shore power (AND ITS NOTTTTTTT A TRANSFER SWITCH PROBLEM) it could be the shore power has a bad/loose/resistive connection or the power cord has a bad conductor, maybe it or a connection got burned when things overheated (including possibly an open Neutral). Remember even if you read full voltage unloaded a bad connection or conductor can cause V = I x R Voltage drop so things still don’t work when using shore power !!!!!!!!!!!

 2)      You state: “Mysteriously, however, the solar inverter powers the entire RV system just fine. The shore power connection does not power the RV’s electrical system, even though I can read the 120 volts at the 30 amp breaker connection in the power panel. I do not understand that at all.

MY THOUGHTS    See the above, even if you read full voltage a bad/loose connection or a bad cord can cause the RV to NOT work or an open Neutral may be the problem. ALSO if you're relying ONLY on the TS to transfer the panel over to shore power it may be at fault . I CANT KNOW HOW YOU BY PASSED OR HAVE IT WIRED TO SEE IF THE TS OR SHORE POWER IS THE PROBLEM

 3)      You state: “ With my limited electrical knowledge, the only variable I could figure was the grounding from/in the old power pedestal. But, I do not have enough knowledge to figure how or why that would be the case? The solar system is directly grounded to the RV chassis and completely separate from the 120 volt electrical system until the connection at the A-B switch and then to-and-through the power panel. Interestingly, the built-in 3600 kw Cummins/Onan genset (one reason why I bought this older RV) is also grounded directly to the RV chassis.

MY THOUGHTS   Solar panels may or may not be grounded to the RV and a Genset or Inverter has its NG Bond tied to the RV frame but I dont see that as your problem. I don’t think you understand Grounding in the old power pedestal so read what I typed above.

 4)      You state: “   So my conclusion today is that the problem IS likely something in the shore power system, possibly something to do with the grounding (since grounding is the only variable I see)? It is a very, very old pedestal at this very old RV park where I am staying, which is owned and run by the city.

 MY THOUGHTS  I agree the problem is likely in the shore power system including the pedestal itself !!!!!!!!!!!!  UNLESS HOWEVER not knowing how you have wired the Transfer Switch or how you by passed it THE TRANSFER SWITCH ISNT PASSING SHORE POWER THROUGH TO THE MAIN PANEL . If its not working or wired right or has a bad connection, even perfect shore power wont work !!!!!!!!

 To know for sure if you can isolate and re wire shore power DIRECT TO THE MAIN PANEL to see if that works or not ??? will show if shore power is good or bad TRY THAT and insure the TS is wired right and working with good connections

 5)      You state: “I don’t really know how to check the pedestal further (until I read your message from today again and again) in the morning

 MY THOUGHTS see what I typed above for how to check voltage at pedestal and what you should read if alls well

 6)      You state:  “It is a 50 amp ONLY pedestal with NO BREAKER. I do have a surge protector plugged into the 50 amp power source through my 50-30 amp dogbone, and then to my shore power cord.

MY THOUGHTS   Are there any error codes on your surge protector???? IT COULD BE THE PROBLEM  What are the voltages after the dogbone adapter???? See my above for what they should be

 7)      You state: “ As I came to the conclusion the pedestal and grounding therein could very well be the problem (before I read your detailed information), I also realized that IF there is a grounding or other problem in the old pedestal’s wiring, that also likely would have contributed to the overheating and burn-up of the old shore power twist-lock plug.

 MY THOUGHTS That could well be possible !!!!!!!!!!!! The shore power problem could be in the Pedestal (burned loose or resistive connection) or improper NG bonding and grounding OR IN YOUR POWER CORD OR A CONNECTION or a bad/open/loose Neutral coupled with other simultaneous faults or shorts. Again the TS could be the problem !!

 You state: “Please, please, don’t spend any more of your time until I get through the next steps in my testing.  I’ll let you know tomorrow whatever I find.

MY THOUGHTS no problem in helping you I'm glad to do so and I'm looking forward to what you find

If you work through all the step by step detailed instructions I posted above and then work through those I added here and answer the questions I posed, hopefully we can figure this out. Based on your most recent information, here are my new thoughts as to the problem

NEW ONES A loose or open or resistive NEUTRAL with simultaneous faults may be the problem. Such can cause all sorts of weird problems and hazards………..Incorrect NG bonding or mix n matched Neutrals and Grounds or improper dual/extra NG bonds. The overheating may have caused some internal opens and some conductor shorts

OLD ONES if it’s a shore power problem the problem may be 1) In the pedestal 2) In the cord 3) A bad connection 4) A bad or incorrect wired plug or receptacle or transfer switch  5) The Transfer Switch isnt working to pass shore power through !!!! BE SURE TO BY PASS THE TS TO SEE IF SHORE POWER WORKS THEN ???? REMEMBER full voltage under no load is NOT the same as under load where a line voltage drop can cause things not to work EVEN IF VOLTAGE IS FULL OTHERWISE

ONE MORE THOUGHT  When the cord and other components overheated the Neutral could have burned open and/or the Neutral and Ground may have got bonded together !!!!!!!!!! YOU REALLY NEED TO CHECK AND OHM OUT THAT POWER CORD  There should be near zero ohms end to end of each conductor yet no continuity between any one to another... CHECK THAT....

CORD TESTING  With an ohm meter to test for each leads continuity and resistance PLUS to look for shorts from one wire to another flex n bend the cord at the same time looking for problems !!!!  If a Neutral were totally open (NOT resistive) there would be no voltage Line to Neutral HOWEVER with overheating there could be other shorts or alternate current paths. If the Neutral were not total open yet resistive, again under load there would be voltage drop so appliances may not (subject to voltage drop) function.  

 Best wishes Jim, hope this and all I posted above helps, work through my suggestions, answer my questions, and let me know what you find. It would really really help to know if you totally (with proper safe isolation) by passed the transfer switch and connected the RV's main panel to shore power to see if it works then ??? If so shore power is okay, if not shore power is the problem  EASY PEASEY TEST let me know about all that... 

NOTE Im running out of ideas here so if anyone has more suggestions or ideas as to the cause, PLEASE ADD TO THESE LOL Im sure I missed some possible causes grrrrrrrr my bad so educate myself and all here as to other possible problems 

John T NOTTTTTTT any Solar Expert so see what the experts have to say. My experience and expertise is in Electrical Power Distribution Engineering instead of how your solar system functions and your switching configuration.

Edited February 14, 2022 by oldjohnt

[Darryl&Rita]

My thoughts: If the inverter is connected to the "Gen" terminals, and powered up, the transfer switch will never select pedestal power.

[oldjohnt]

10 hours ago, Darryl&Rita said:

If the inverter is connected to the "Gen" terminals, and powered up, the transfer switch will never select pedestal power

Thats typical on the ones I've owned, if the gen is working the TS doesn't go over to shore power...However my TS doesnt transfer until after a time delay to allow time for the genset to stabilize. I cant be sure how he is using or configured the TS or has tried to by pass the TS to insure shore power or the TS is the problem..   

John T

Edited February 14, 2022 by oldjohnt

[Kirk W]

5 hours ago, jesfl45 said:

What can I ever do to repay you for your extraordinary assistance?

Nothing at all needs be done as your thank you is plenty. Helping each other is what the Escapees club is all about and I help you as repayment for those who have helped me in the past. Also, I enjoyed the challenges presented in troubleshooting and still do, but at times like this I do wish that I were nearby and could get my hands and my meter on things!

5 hours ago, jesfl45 said:

With my limited electrical knowledge, the only variable I could figure was the grounding from/in the old power pedestal.

I suggest that you watch this video before you go back to work. It will explain how to check out both a 30A and also the 50a RV outlets.

How to test RV power pedestals before plugging in!

Also it is a very good idea to write down the readings you get and where they were taken and to even do a simple drawing of what you are examining. That is one of the basic troubleshooting techniques that most experienced technicians learn. 

5 hours ago, jesfl45 said:

Please, please, don’t spend any more of your time until I get through the next steps in my testing.

I will be out of pocket until afternoon tomorrow so I'll be looking forward to your latest update. If I should happen to have any sudden burst of ideas, I'll keep you informed. 

[jesfl45]

 

Kirk, John T, Darryl&Rita, et.al.,

Again and again, thank you all so much.

John T, Darryl&Rita:  Yesterday afternoon -- after 6 hours of morning electrical frustration -- as I was skimming the messages in this forum, I didn't even see your additional names on responses. I apologize for not noticing. At that point in my day, I was at my mental max.

This morning, I'm again trying to absorb, but I'm kinda' in the zone of "waaaaay too much information." I’m about to start reading through all of your comments again and testing everything, as you suggest.

You are wise to understand that my electrical knowledge is limited, generally just enough to get by, most times. Uncommon issues are my nemesis/downfall.

During the past two years of my RV travels I have found myself constantly asking myself the question: "Why do I need to know (or do) that; and/or why do I care?" I am always trying to simplify and eliminate, which fits my elderly brain much better.

To wit:

(Automatic) Transfer switch:  IT IS GONE!!! It is completely out of the picture. Please forget about it. I don't want one. I don't need one. In my testing yesterday (Sunday) morning, I wired around it. Then I realized my first solution of wiring both the genset and the solar inverter through an A-B switch (marine battery-type) into the transfer switch was a classic "Rube Goldberg" mess. Solution: This morning I ordered:

I lived on a boat for a couple of years and had a similar switch, I remembered. It was perfect then and it will be a much better solution for my RV since I seldom will use anything other than my solar system’s inverter, probably 90% of the time. The genset and shore power are emergency-only elements of my system.

I am beginning again the re-testing of everything . . . I dunno’, probably the 5th or 6th time around.

By the way, I previously found the NRVTA “Todd Tech Tip” video about testing the pedestal connections early last week during my current electrical odyssey. But, I’m gonna’ watch it again now just to check myself and be sure I didn’t misunderstand something . . . before I start the testing again. Also, until Saturday, I was using my deceased father’s basic 30+-year-old (?) analog multimeter (needle scale type). I now have my new higher-quality clamp-type multimeter. Much better.

I’ll let you know all of the data I collect later, most likely tonight.

Thanks to all, once again.

Jim (jesfl45)

[oldjohnt]

1 hour ago, jesfl45 said:

John T, Darryl&Rita:  Yesterday afternoon -- after 6 hours of morning electrical frustration -- as I was skimming the messages in this forum, I didn't even see your additional names on responses. I apologize for not noticing. At that point in my day, I was at my mental max.

No apology needed, alllllllllll of us are here to help and glad anytime we can, with so many helping I know its hard for you to keep up lol. Try our tips ONE AT A TIME as we may have different ideas. WATCH IT BE SOMETHING SO SIMPLE WE ALL MISSED IT grrrrrrrrrrrrr 

 

1 hour ago, jesfl45 said:

This morning, I'm again trying to absorb, but I'm kinda' in the zone of "waaaaay too much information." I’m about to start reading through all of your comments again and testing everything, as you suggest.

Don't be in any hurry, take my troubleshooting tips ONE AT A TIME. The reason we have to offer so much is because were not there to find out for ourselves so have to cover so many different bases.  

1 hour ago, jesfl45 said:

(Automatic) Transfer switch:  IT IS GONE!!! It is completely out of the picture. Please forget about it. I don't want one. I don't need one. In my testing yesterday (Sunday) morning, I wired around it

THANKS FOR THAT UPDATE  if the ATS is gone you need to ignore all my tips above regarding it as the cause. BOTTOM LINE if the RV main panel is wired to shore power and its NOT working PROBLEM MUST BE IN THE SHORE POWER such as 1) An open or burned/resistive or partly shorted cord conductor,,,,,,,,,,,,2) Pedestal power,,,,,,,,3) Plug or receptacle or a connection,,,,,,,,In which case look at my methods above of how to use an ohm meter to test the cord for bad or shorted wires while flexing it,,,,,,,,How to check for voltages at the Pedestal (120 L1 or L2 to N OR G, 240 L1 to L2) and AFTER the 50 to 30 dogbone adapter (120 L1 to N or G) AND REMEMBER voltage may be fine with no load but when a load is applied Voltage Drop occurs so appliances many still not function.

Checks voltages voltage at pedestal and then at the main panel input with all off and main breaker open, then turn it on and other breakers and loads to see voltage then ??????????????? If it drops drastically THERES A BAD/LOOSE/RESISTIVE wire or cord or connection in your RV portion orrrrrrrrrrr at the Pedestal

NOTE you can have a wire or cord with only one teeny wire strand left in place and attached YET THE VOLTAGE CAN STILL CHECK FINE WITH NO LOAD ........But as soon as you apply a load the voltage can drop and/or that small remaining wire burn open WIRES, CORDS, CONNECTIONS CONNECTIONS, CONNECTIONS could be the only problem, in the Pedesatl or in your RV !!!! 

 Thats enough for now I dont want to overload you lol 

Theres more to be said about AB switches and Grounding and Bonding or floated, switched or non switched Neutrals etc etc but no way Im going there now.

Check voltages per the above at pedestal and at main panel with NO loads then turn things on, check again and LET ME KNOW YOUR FINDINGS

 You're most welcome, Thanks for the updates, Im glad to help, were going to get this yayyyyyyyyyy

John T  Long retired power distribution engineer BUT NOT ANY SOLAR EXPERT so hope they can add to this        

Edited February 14, 2022 by oldjohnt

[Wrknrvr]

    I have reading this subject some. Sorta overwhelming to just read it twice and to understand it.

   I would suggest,if possible to check with your neighbor to see if you could hook up to his power pedestal. I have seen where a rv park will do that to disprove or prove the park has a problem.

 

  You need to find enough extensions to do that connection.

  The other thing I have seen is a controlling connection be bad. It could be anywhere in your system. What I am saying is that a 12 vdc fuse can look good, test good but be bad. I have seen that a number of times in the past years.

  Also does your inverter have a pass through switch in it, that passes shore power through it. Bad switch.

    Maybe wiring schematics would give us a better possibility to pinpoint your problem. 

  Just thinking,    Vern   

 

    Vern

   Just some different thoughts.

   Vern

[jesfl45]

 

Good morning, again. (Much earlier today than planned.)

And, Vern, thanks you. I just saw your additional comments. 

I've completed the first round of testing from the 50 amp pedestal connection to my power panel.

The readings at every connection point are 123.5 volts (+/-) with a very slight variance . . . and that includes the main 30 amp breaker at my power panel. I did get a slight variation with readings of 122.5v to 122.9v at the power panel, too.

However, there is no 120 volt power to anything in the RV when any or all of the remainder of the 15/20 amp circuits are turned on. So, power in. No power out.

I now suspect, as suggested above, the problem is the load thing . . . that "with a load" there is inadequate power because of a problem in/at the power pedestal.

Why is that my focus and hypothesis, you ask? While testing the pedestal this morning, a permanent resident neighbor at this RV park stopped by and said "you should just move, others have had to move because they had problems with that power outlet, too." He went on to say he was very surprised that they even put me in the RV space because of the past problems. Of course, I agreed with him. And, offered a big thank you. And then thought to myself, 'wow, that's pretty darned telling . . . '. )

So, I'm betting that if I moved to another lot here at the RV park the shore power problem would go away. But, since I'm only going to be here another 2 weeks, I'd rather not go through the hassle of moving since I'm well set up in this lot. 

Even so, I'd still like to diagnose the problem more precisely as a learning experience.

I'd also like to be 100% positive about the answer to "why" my solar inverter 123v output runs all my RV AC power outlets and appliances . . . when the shore power 120v AC will not? At this moment, my assumption is that happens because my solar inverter handles a load -- including my 1500 watt microwave and the 1500 watt heat gun I used yesterday, etc., etc. . . . all with no hiccups. But the 120v shore power will not handle any load because of the pedestal problem?

And, I'd like to understand why the shore power here worked fine for 2-1/2 months before I overheated the shore power plug with my AC, hot water, etc., etc. all turned on at the same time? And, of course, why doesn't/won't it work now with the same exact wring setup, but a higher quality shore power connection?

BUT, let's start with STEP 1 before tackling other questions. So, how do I add a "load" to check -- as was suggested above -- when none of the appliances or outlets in my RV are "live" even though there is 123v of power at the main/incoming 30 amp breaker?

Alternately, is there another way to prove/demonstrate the problem with the 50 amp pedestal outlet?

Suggestions?

Thank you one and all, once again.

Jim (jesfl45)

P.S.  An afterthought from a previous question above. No, 120v shore power does not run through my solar system or the solar inverter in any way. The solar system is completely isolated. Shore power is direct to my power panel. The generator is also isolated, because after I set up the first part of my solar system, my then single LiFePO4 (200 Ah) battery had trouble "cranking" my genset if it was not fully charged and/or getting additional solar panel current. So I kept my 2 previous AGM batteries and wired those to the genset for starting only (or non LiFePO4 power) in an emergency. Two years ago when I started installing solar, I removed the 18-year-old WFCO converter/charger in the WFCO power panel and replaced it with a Progressive Dynamics, Inc. lithium converter/charger. I have only charged my lithium batteries through that converter 4 times when running the genset as occasional tests (after I turn off the separate system isolation breaker I installed right at the solar system, of course).

 

 

 

[Wrknrvr]

    First of all, I chased a 12vdc head light problem in my Volvo truck. The right head light worked when it felt like it.

  Traced all connections, installed a new dash light switch. Worried about darn head light for three years pulling our fifthwheel. I checked all my connections I could find even with service documentation.

Extremely frustrating. So last summer I had fiddling time to check it again. The connections at the head light finally failed enough to solve my problem. Notice I said enough, it has been a problem for some time and finally failed so I could find it. I was using a volt meter and a tone generator. Neither would pickup where the problem was. Until it really quit.

 

   Where does your shore power hook into your inverter house wiring?

Our fifthwheel is 43’ long. The shore power is a twist-lock connection at the rear of the fifthwheel. But I wanted to power the rv from the generator on the truck or from shore power to the front of the rv. So I installed a twist-loch device on the front of the rv under the overhang of the fifthwheel. That way I had a place to plug in generator or font access shore power.

   The rear shore power was installed in the shore power side of a auto transfer switch. The front was wired into the generator side of the auto transfer switch.      Then the house side of the auto transfer switch was wired into the invert/ charger that has a built in auto transfer switch to pass through shore power.

 

    So that is why I question where the two powers supply the house , that is a common location.

    You could just use a 12 gauge extension cord for a test from another power pedestal. Just do not use any heavy loads.  Be cautious on that subject.

 

   Vern 

Edited February 14, 2022 by Wrknrvr

[jesfl45]

Vern, 

Thank you for the ideas.

I get that the problem might be something that just hasn't "completely" failed yet. And, my focus for that remains the (very old) 50 amp power pedestal to which I have been connected.

That's because, I just just checked continuity on all of my power supply cables and all is well there with both the dogbone (50 amp-30 amp) and my pedestal to RV power cord. But, just to be safe I took the new SmartPlug female half off my power cable, cut another foot off the power cable, and rewired the plug. Someone mentioned the heat from the previous failure might have caused an issue, AND I wanted to quadruple check my own wiring for the new plug. I'm confident it is not the power cables.

To your specific question, my shore power connects to my WFCO power panel through about a 8'-9' length of 10/3 wire covered with a protective plastic housing (original Coachmen construction) from the rear of the RV (at my new SmartPlug) through the floor to the power panel. So, a pretty short run and a very direct connection. I have checked continuity of that wire and it is fine. When I started my solar installation with LiFePO4 batteries 2 years ago, I replaced the then existing WFCO converter/charger that was built into the power panel with a new Progressive lithium-only converter/charger. I mention that again, because I also added a breaker to my power panel specifically for the lithium converter/charger. In nearly two years, I have never used that new $250 lithium converter/charger, so it was a waste of my money unless I rationalize that it is "insurance" in case of a solar system failure. I only turn it on occasionally to test when I exercise my genset, which I also seldom use. 

The solar charge controller and the 3000 watt inverter in that system is in the front of my RV. It is a completely isolated system. Shore power does not connect to the solar system at all. Solar inverter power runs to the power panel through a 30 amp switch, which I am replacing with a better solution (previous comment).

I've already removed my 16-year-old (?) automatic transfer switch. It will be in Thursday's trash. As far as I'm concerned, it's pretty useless and just another mechanical device that can fail. At very least, it is in the way in my limited cabinet space for which there are much better uses.

I surely wish I could plug into another nearby power pedestal with an extension cord. But, the only other pedestal within 50 feet has only one working 50 amp connection which is in use by another RV'er. Now, get this: the 30 amp connection on that pedestal has a "home dryer-type" female plug in it, not even a 30 amp RV connector. The next closest pedestal is 150 feet, or so, away. That dryer plug should have been a very big red flag for me when I got here a couple of months ago, but this spot was the only place I could find on short notice back then. I guess I could make myself a little dryer-plug to RV 30 amp plug dogbone? Naw, not worth the trouble.

Thanks again. Any other thoughts are certainly welcome.

Jim (jesfl45)

 

 

 

 

 

[Wrknrvr]

  Just thinking,     Will the generator now energize your lithium charger.

 

   Now your solar powers the 110 circuits in your rv. Is that correct.

 

  But your shore power will not. Is that correct.

 

  If so, start at the point where they both feed power to the Ac circuits. And work backwards.       I would also watch for Ac voltage very accurately.   That may give a point of interest.

 

 

    Vern.

 

   My wife has been pestering me to fix my heater system in my 1990 Jeep yj.    So I was investigating that subject today.

  Yea she was sorta stepping on my toes to fix it. It’s only been 10 years until I finally realized it needs fixed. I am making progress.

 

 

[oldjohnt]

8 hours ago, jesfl45 said:

However, there is no 120 volt power to anything in the RV when any or all of the remainder of the 15/20 amp circuits are turned on. So, power in. No power out.

I now suspect, as suggested above, the problem is the load thing . . . that "with a load" there is inadequate power because of a problem in/at the power pedestal.

Sounds right, even with a bad cord or connection or a pedestal power problem you can still read 120 NO LOAD but much lower so things don't work UNDER LOAD... However the problem may be in your cord or a bad connection instead of the pedestal   HOW TO TELL WHICH   measure the voltage at the pedestal BOTH LEGS under load (apply loads by switching main and branch breakers in panel on one at a time) and at the RV main panel input under load..........If its low out of the pedestal there's the problem HOWEVER if its still 120 out of the pedestal but low at the RV panel the problem is Yours such as the RV cord or a bad connection..........NOW THATS NOT A DIFFICULT TEST YOU CAN EASILY PERFORM......Is the voltage drop problem in the Pedestal orrrrrrrrrrrrrr in your RV cord or connections or plugs etc   

 

8 hours ago, jesfl45 said:

I'd also like to be 100% positive about the answer to "why" my solar inverter 123v output runs all my RV AC power outlets and appliances . . . when the shore power 120v AC will not? At this moment, my assumption is that happens because my solar inverter handles a load -- including my 1500 watt microwave and the 1500 watt heat gun I used yesterday, etc., etc. . . . all with no hiccups. But the 120v shore power will not handle any load because of the pedestal problem?

You answered your own question: The Inverter is producing adequate power while the Pedestal or your RV (cord or a connection or plug etc) is not due to a resistive voltage dropping problem 

8 hours ago, jesfl45 said:

And, I'd like to understand why the shore power here worked fine for 2-1/2 months before I overheated the shore power plug with my AC, hot water, etc., etc. all turned on at the same time? And, of course, why doesn't/won't it work now with the same exact wring setup, but a higher quality shore power connection?

When it worked there were no bad/loose/resistive voltage dropping connections but now there are. And where is that problem ??? Pedestal or your RV FIND OUT WHICH BY READING MY FIRST RESPONSE ABOVE

 

8 hours ago, jesfl45 said:

So, how do I add a "load" to check -- as was suggested above -- when none of the appliances or outlets in my RV are "live" even though there is 123v of power at the main/incoming 30 amp breaker?

See above, turn off the RV panels main breaker,,,,,,,,Rig up a means to measure voltage out of the Pedestal,,,,,,,Rig up a method to measure voltage at main panel input,,,,,,,,turn on main then branch breakers one at a time,,,,,,,,,,,see what voltage is out of the pedestal (BOTH legs) and at the panel   IF ITS LOW AT PEDESTAL ITS THE PROBLEM,   IF ITS OKAY THERE BUT LOW AT PANEL, THE RV WIRING IS THE PROBLEM (cord or connections or plugs or wiring EASY PEASEY

 

8 hours ago, jesfl45 said:

Alternately, is there another way to prove/demonstrate the problem with the 50 amp pedestal outlet?

YES measure voltage at pedestal (BOTH legs) under load, if its low Pedestal is the problem, if its fine but low at panel your RV wiring is the problem  (cord or plugs or connections)

ALL IT TAKES TO SOLVE WHERE THE PROBLEM IS LOCATED ARE TWO VOLTAGE READINGS AT PEDESTAL AND MAIN PANEL INPUT AS BREAKERS ARE SWITCHED ON AND CURRENT FLOWS                                                                             TRY IT !!!!  

NOTE at a proper wired and working pedestal again I would expect 120 VAC from EITHER L1 or L2 to Neutral and EITHER L1 or L2 to Ground and 240 VAC L1 to L2. Then if you draw current those can drop some based on the amount of current flow, but even at say 20 or 30 or more amps NOT THAT MUCH LOWER           UNLESS    THERES A BAD/RESISTIVE CONNECTION OR OTHER PROBLEM WHICH A PROBLEMATIC PEDESTAL COULD INDEED EXHIBIT.

NOTE your 50 to 30 Amp Dogbone Adapter simply uses one of the 50 Amp L1 or L2 legs to feed your 30 Amp RV its 120 VAC 30 Amp service  

 I WOULD JUST PLUG INTO A DIFFERENT PEDESTAL THATS SOOOOOOOOOOOOOOOOO EASYYYYYYYYYYYY to tell if your Pedestal is bad......  Ive seen older pedestals with burned connections or loose ones and carbon and arcing and loose or resistive Neutrals that can cause all sorts of problems grrrrrrrrrrrrrrrrrr 

MORE QUESTIONS ??? If so let me know

John T

Edited February 15, 2022 by oldjohnt

[Kirk W]

6 hours ago, jesfl45 said:

So, I'm betting that if I moved to another lot here at the RV park the shore power problem would go away.

No question that a move would be the quickest way. In lieu of that, try and locate an extension cord or 2 from other RV owners or at least 30A that you could then string from your dog-bone adapter. 

6 hours ago, jesfl45 said:

Two years ago when I started installing solar, I removed the 18-year-old WFCO converter/charger in the WFCO power panel and replaced it with a Progressive Dynamics, Inc. lithium converter/charger.

I am no fan of WFCO products and have replace mine with General Dynamics as well.

Also as a heads-up, I am home from outpatient surgery so will be mostly riding my recliner for a day or 2 and working on your problem will help to keep me from going stir-crazy! I am still wading through the posts above this one so have not yet gotten to a point of any additional advice. I will also send a Private Message shortly.  😊

 

[oldjohnt]

2 minutes ago, Kirk W said:

I am home from outpatient surgery so will be mostly riding my recliner for a day or 2 and working on your problem will help to keep me from going stir-crazy! I am still wading through the posts above this one so have not yet gotten to a point of any additional advice. I will also send a Private Message shortly.

Kirk sorry to hear, I hope alls well and you get well soon, keep us posted and if you come up with more ideas of the problem and how to fix it PLEASE LET US ALL KNOW !!!!!!!

 Best wishes, take care and God Bless

John T

[Kirk W]

53 minutes ago, oldjohnt said:

I hope alls well and you get well soon,

Thank you for the kind thought! I'll do so but this was just a senior male visit to the local plumbing shop & plumber. Something the doctor says that all men get eventually if they live long enough. The age it happens varies widely but tells me that all men eventually have to see a urologist Said that it is a very secure side of medicine!   😏

On the PM, I went that way because the subject was far off topic and didn't wish to hijack his important thread, so enough about plumbing and back to electrical issues! 

[oldjohnt]

29 minutes ago, Kirk W said:

On the PM, I went that way because the subject was far off topic and didn't wish to hijack his important thread, so enough about plumbing and back to electrical issues

Thanks for the added info Kirk, wish you the best.

John T

[Wrknrvr]

    I was reading in the beginning of this topic where you connected your inverter power to the transfer switch . Or somewhere and your house power worked.

   I was thinking if you disconnect your inverter power from where it is attached now. Take a appropriate short adapter that you could plug your shore power cord into. And cut that short plug adapter in the middle, attach it to your inverter.        Now you have a known power source that you can plug into.   

  Now you can eliminate the shore power pedestal question.

 

    I did mobile rv repair for 12 plus years. Early on I realized I needed a way to test power from pedestals or other such places. So I bought short adapters, 30 & 50 amps, cut them in half, and now I could test power much easier. Just be careful when doing such testing. 

 

   Thinking,     Vern