Jump to content

shore power with gfci breaker(30A) tripping


Recommended Posts

2 hours ago, Ogrape1 said:

 When I plug my 2019 Orion T24RB motorhome in to shore power (110 volt, 20 amp) the shore outlet's GFCI (at home) or breaker (at campgrounds) immediately trips.

That is quite normal. Your RV is teated electrically like one big appliance and it has GFCI procteted circuits and if you feed a GFCI from a GFCI the second one will trip. Your tests demonstrate that fact quite well. It takes some understanding of electrical theory to understand what is happening. 

Edited by Kirk W

Good travelin !...............Kirk

Full-time 11+ years...... Now seasonal travelers.
Kirk & Pam's Great RV Adventure

            images?q=tbn:ANd9GcQqFswi_bvvojaMvanTWAI

 

Link to comment
Share on other sites

GFCI will trip whenever a 5ma imbalance between the nuetral and nongrounded line exists. Multiple GFCI protection will not by itself cause tripping.  With such small imbalance many things can cause the problem and RV's don't play well with GFCI  power.  RV parks are exempt from GFCI for power receptacles but all outside residential circuits now require GFCI.  By spending many hours I have found and cured RV GFCI tripping but it often isn't easy.

Edited by Randyretired

Randy

2001 Volvo VNL 42 Cummins ISX Autoshift

Link to comment
Share on other sites

16 hours ago, Kirk W said:

if you feed a GFCI from a GFCI the second one will trip. Your tests demonstrate that fact quite well.

   I never heard that ?? (agree with Randy on this one) I don't understand why that's true but am a longggggggggg retired EE and things may have changed?? but I'm never too old to learn if that's the case.  Sure, if a second GFCI senses a ground fault (5 ma or more) it will indeed trip, HOWEVER, I don't understand just because it's fed by a GFCI that by itself will cause it (second one) to trip ????  Hopefully someone can explain that for all our benefit.

15 hours ago, Randyretired said:

GFCI will trip whenever a 5ma imbalance between the nuetral and nongrounded line exists. Multiple GFCI protection will not by itself cause tripping

  X2  Randy, FWIW Thats how I was trained and understand it. A GFCI functions by the Hot/Line and Neutral passing through a Torroid Coil so if the outgoing Hot current is alllllllllll returned by the Neutral there's no current differential, no voltage is induced into the coil, NO TRIP.

 Having owned RV's for 50 years (before GFCI was even a thing) its been my experience with all the possible moisture, dust, dirt, humidity, internal and external outlets, sorted appliances, and the fact it ONLY TAKES 5/6 MILLIAMPS of fault current to trip, THATS WHY RV'S PLUGGED TO GFCI ARENT FRIENDLY. 

Randy PS, I like your use of the terminology as when I practiced and attended NEC Seminars the Neutral was referred to as the GROUNDED Conductor and the Hot/Line as the UNgrounded Conductor which is true, just not heard so much outside electrical circles.   

Love this sparky chat and the forum so maybe we can all learn more about GFCI's in this thread.

 Best wishes to all here, take care, be electrically safe !!!!

John T  Retired but still willing to learn.

 

Edited by oldjohnt
Link to comment
Share on other sites

Interesting to read it was not just us. Way back ~ 1998-2000, when we were fulltiming, we stayed overnight on the way back to our Louisiana winter quarters we stayed at Little Rock AFB FamCamp (Military RV Park) and they had a GFCI on their RV pedestals. Mine kept tripping the GFCI, and we thought it was our rig. It wasn't us and we never had that problem before or since. Good info, glad they stopped requiring it for RV pedestals.

RV/Derek
http://www.rvroadie.com Email on the bottom of my website page.
Retired AF 1971-1998


When you see a worthy man, endeavor to emulate him. When you see an unworthy man, look inside yourself. - Confucius

 

“Those who can make you believe absurdities, can make you commit atrocities.” ... Voltaire

Link to comment
Share on other sites

The quasi mystery still for me is why this suddenly happened after months and months and months of connecting the same 30A shore power line with adapter to the same 20A GFCI outlets in my garage.  I do not know of one change in any of the RV's equipment or devices, and no changes in the house/garage either.

I can't see how turning on the inverter prior to connecting to the 20A GFCI shore power, as some have suggested here and on other sites, will work with the way my inverter is wired (rough schematic attached).  The inverter sends power to everything that is 110v. in the coach.

Thanks to all who have pitched in here.  I appreciate it.

PXL_20221022_215056272.jpg

Link to comment
Share on other sites

49 minutes ago, RV_ said:

Interesting to read it was not just us. Way back ~ 1998-2000, when we were fulltiming, we stayed overnight on the way back to our Louisiana winter quarters we stayed at Little Rock AFB FamCamp (Military RV Park) and they had a GFCI on their RV pedestals. Mine kept tripping the GFCI, and we thought it was our rig. It wasn't us and we never had that problem before or since. Good info, glad they stopped requiring it for RV pedestals.

There is most likely a problem in an RV that trips a GFCI but it may be very minor.  To give an example I had a GFCI 50amp that would periodically trip.  I finally found a spider web in the receptacle box.  Once I removed it it hasn't tripped since.  With all of the circuits in an RV it can be a nightmare to find.  I plug our 5er into a 50amp GFCI at home and it finally operates after a lot of work.  That is until the mini split compressor kicks on.  Something in the inverter circuitry trips it immediately.  GFCI are a great safety feature but when there is a problem it can be difficult to locate.  The code now requires all outdoor residential circuits to have GFCI.  Even 30 and 50amp receptacles so more of us may run into this when we plug our rigs in at home.

Randy

2001 Volvo VNL 42 Cummins ISX Autoshift

Link to comment
Share on other sites

Randy,

Most of the campers with the "New" pedestals that night, Halloween, had the same problem with it tripping as soon as it was plugged in.

I always plugged in an outlet tester before plugging in to check for issues. I never had that RV trip any breakers anywhere in seven years of full-timing just there. I did find some miswired and got moved to another site when I found those, one in Utah, and One in Alaska. That was a 30 Amp rig.

RV/Derek
http://www.rvroadie.com Email on the bottom of my website page.
Retired AF 1971-1998


When you see a worthy man, endeavor to emulate him. When you see an unworthy man, look inside yourself. - Confucius

 

“Those who can make you believe absurdities, can make you commit atrocities.” ... Voltaire

Link to comment
Share on other sites

Ogrape and RV, good morning, FWIW here are one electrical power engineer and lawyers thoughts:

1) For whatever reasons, lawyers fearing liability or engineers representing an RV park may have insisted upon some sort of GFCI protection (regardless if code requires or not) be it at individual receptacles or GFCI breakers and as the effects are cumulative and it takes ONLY 0.005 amps to trip ONE OR MORE RV'S PLUGGED INTO GFCI PROTERCTION CIRCUITRY CAN EASILY CAUSE A TRIP.

2) As I mentioned before the slightest excess moisture or humidity, dirt or dust, insects, all the sorted appliances, RVs with external receptacles, and the fact ground faults can be cumulative (one or more RV's) MAKES IT SO EASY FOR RV(s) TO TRIP A GFCI 

3) There could be some issues (Inverters or Generators) with the NECESSITY THERE BE ONLY ONE NEUTRAL GROUND BOND. When an Inverter or Genset is configured as a Separately Derived Source with a BONDED Neutral and the RV frame serving as the Grounding Electrode, depending on how the transfer arrangement is configured (How many poles, Neutrals switched or not???)  THOSE DEVICES CAN CAUSE A GFCI TRIP if there are multiple Neutral/Ground bonds. In order to avoid having more than one NG Bond (AS I understand but NO warranty) some transfer switches bond the gensets Neutral when its in use but open it otherwise and similar some Inverters use some sort of a bonding relay ONLY when the Inverter is operating THOSE ARE TO PREVENT MULTIPLE NG BONDS which could cause GFCI problems. Not long ago when on Inverter power a GFCI tripped instantly when my microwave started but when I plugged it into a different outlet (still on GFCI but different location) it worked TALK ABOUT A MYSTERY the problem appeared to be a CIRCUIT (still worked otherwise) instead of the microwave. 

DISCLAIMER These issues are complex and deep in the weeds difficult to trace and diagnose even if there let alone over the net grrrrrrrrrrrrrrrrrrr

4) DIAGNOSE  One method I've used is to one at a time remove/unplug/disconnect/flip breakers feeding loads, appliances or circuits to locate the problem, WHICH MAY BE AN APPLIANCE ITSELF OR THE CIRCUIT/OUTLET STRIP feeding it.  

BOTTOM LINE I just cant from here diagnose YOUR problem, but the FIRST suspects are the RV,,,,,,,,Or the parks service is GFCI protected perhaps with a breaker,,,,,,,,,,Or an Inverter/Generator bonding issue,,,,,,,,,Or multiple NG Bonds,,,,,,,,,,, Or some sensitive electronic devices FOR REASONS I CANT EXPLAIN ESPECIALLY ON START UP  cause a GFCI to trip.

 Sorry no answers just theory and suspicion, but I try my best.

John T   BSEE,JD

Link to comment
Share on other sites

One 30 amp RV I worked on that was tripping a GFCI, would trip on any load from any breaker. It turned out to be the water heater element.  The only way to isolate the problem was to disconnect the nuetrals in the breaker box and reconnect them one at a time with a small load on a circuit that didn't trip.  The common nuetral was feeding back to the ground just enough to trip the GFCI.

Randy

2001 Volvo VNL 42 Cummins ISX Autoshift

Link to comment
Share on other sites

8 hours ago, oldjohnt said:

Ogrape and RV, good morning, FWIW here are one electrical power engineer and lawyers thoughts:

1) For whatever reasons, lawyers fearing liability or engineers representing an RV park may have insisted upon some sort of GFCI protection (regardless if code requires or not) be it at individual receptacles or GFCI breakers and as the effects are cumulative and it takes ONLY 0.005 amps to trip ONE OR MORE RV'S PLUGGED INTO GFCI PROTERCTION CIRCUITRY CAN EASILY CAUSE A TRIP.

2) As I mentioned before the slightest excess moisture or humidity, dirt or dust, insects, all the sorted appliances, RVs with external receptacles, and the fact ground faults can be cumulative (one or more RV's) MAKES IT SO EASY FOR RV(s) TO TRIP A GFCI 

3) There could be some issues (Inverters or Generators) with the NECESSITY THERE BE ONLY ONE NEUTRAL GROUND BOND. When an Inverter or Genset is configured as a Separately Derived Source with a BONDED Neutral and the RV frame serving as the Grounding Electrode, depending on how the transfer arrangement is configured (How many poles, Neutrals switched or not???)  THOSE DEVICES CAN CAUSE A GFCI TRIP if there are multiple Neutral/Ground bonds. In order to avoid having more than one NG Bond (AS I understand but NO warranty) some transfer switches bond the gensets Neutral when its in use but open it otherwise and similar some Inverters use some sort of a bonding relay ONLY when the Inverter is operating THOSE ARE TO PREVENT MULTIPLE NG BONDS which could cause GFCI problems. Not long ago when on Inverter power a GFCI tripped instantly when my microwave started but when I plugged it into a different outlet (still on GFCI but different location) it worked TALK ABOUT A MYSTERY the problem appeared to be a CIRCUIT (still worked otherwise) instead of the microwave. 

DISCLAIMER These issues are complex and deep in the weeds difficult to trace and diagnose even if there let alone over the net grrrrrrrrrrrrrrrrrrr

4) DIAGNOSE  One method I've used is to one at a time remove/unplug/disconnect/flip breakers feeding loads, appliances or circuits to locate the problem, WHICH MAY BE AN APPLIANCE ITSELF OR THE CIRCUIT/OUTLET STRIP feeding it.  

BOTTOM LINE I just cant from here diagnose YOUR problem, but the FIRST suspects are the RV,,,,,,,,Or the parks service is GFCI protected perhaps with a breaker,,,,,,,,,,Or an Inverter/Generator bonding issue,,,,,,,,,Or multiple NG Bonds,,,,,,,,,,, Or some sensitive electronic devices FOR REASONS I CANT EXPLAIN ESPECIALLY ON START UP  cause a GFCI to trip.

 Sorry no answers just theory and suspicion, but I try my best.

John T   BSEE,JD

oldjohnt and others, I have some good news based on your lengthy but excellent posts.  I unplugged the 14x3 AWG cord from the inverter and... no GFCI tripping when plugging in to 20A shore power.  I'll have to dig deeper but I'm suspecting I have multiple NG bonds.  Having said that, I am tired of digging and kind of like having a solution that is so simple.  We almost always boondock: I can put a "Note to Self" on the shore cord to unplug the inverter before shoring up.

Link to comment
Share on other sites

3 hours ago, Ogrape1 said:

oldjohnt and others, I have some good news based on your lengthy but excellent posts.  I unplugged the 14x3 AWG cord from the inverter and... no GFCI tripping when plugging in to 20A shore power.  I'll have to dig deeper but I'm suspecting I have multiple NG bonds.  Having said that, I am tired of digging and kind of like having a solution that is so simple.  We almost always boondock: I can put a "Note to Self" on the shore cord to unplug the inverter before shoring up.

👍👍👍👍👍

RV/Derek
http://www.rvroadie.com Email on the bottom of my website page.
Retired AF 1971-1998


When you see a worthy man, endeavor to emulate him. When you see an unworthy man, look inside yourself. - Confucius

 

“Those who can make you believe absurdities, can make you commit atrocities.” ... Voltaire

Link to comment
Share on other sites

18 hours ago, Ogrape1 said:

oldjohnt and others, I have some good news based on your lengthy but excellent posts.  I unplugged the 14x3 AWG cord from the inverter and... no GFCI tripping when plugging in to 20A shore power. 

CONGRATULATIONS and thanks for the feedback Ogrape. Its above and beyond figuring out a possible inverter issue over the net, but if you can A) Now use shore power with no problems (with inverter unplugged, don't need it then) and B) dry camp using the inverter with no problems YOURE GOOD TO GO            If it aint broke DONT FIX IT 

FYI heres the theory behind why a multiple NG bond is forbidden and can mess up GFCI..It may NOT be your issue this is ONLY theory NO warranty.

 With a second NG bond there's a dual current return path with BOTH Neutral and Equipment GroundING Conductor (for fault current ONLY) sharing current. A GFCI has ONLY Hot and Neutral flowing through its Torroid Coil and trips if both arent near the same, HOWEVER if the EGC is sharing return current the GFCI sees the imbalance. THAT MAY OR MAY NOT BE YOUR ISSUE OR YOUR INVERTER  its complicated and can NOT be solved over the net this is ONLY an explanation  of why single point grounding/bonding is necessary...

PS when USING an Inverter or Genset they use a BONDED Neutral but that NG bond cant still be in place and connected to shore power when its used DOUBLE NG BOND. Transfer switches or bonding relays (if in place correct and working?)  are methods that can prevent a multiple NG bond.   

Thanks for the kind words Ogrape, yep there are some great sharp gents here who have helped me and Im glad to help when I can, even if I get over techy and bore some non sparkies lol.  I try my best

John T

 

Edited by oldjohnt
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...