Kirk, John. Electrical folks one and all. Please help.

[Daveh]

Hi Guys I am a little stumped. A lot of different things happening and I am trying to isolate.  Right now  I only have AC through my inverter and subpanel.  My Magnum will not recognize the AC and the charger will not run.  I run most of my AC through my inverter and the subpanel. However, the magnum will not pass through any shore electricity so I am just using battery and inverter. It is not only my Magnum Inverter that is refusing the AC from the main panel but I also have our fireplace and washing machine attached to circuits directly from the panel. The fireplace and washing machine also will not work. The fireplace starts but then goes off right away. The washing machine doesn't start at all.

The variables are:

1. My water pump popped its hose and wiring may have been hit. (I did not think so but found moisture in the area of the transfer switch. Specifically, I think the transfer switch may have been hit.

2. I am in a newly built campground and we just arrived yesterday. Unfortunately, I did not do my normal checks so I don't know if the inverter/charger, fireplace and washing machine ever worked or whether things have been nonfunctioning since I got here.

3. I first noticed the problem about 2 hours after we got here and my AC started making a noise like the current had changed--it did it a few times and I shut it off. I do not know whether this happened when I was on the park ac as my inverter will run the AC for a while (Magnum 3012 and I have lithiums) but my first thought was that I had a power surge. 

So my plan was to look for something obvious which I did not find last night. Now I am back at the pedestal and working my way backward.  My readings this AM at the 50 amp pedestal were L1-N 123  L2-N 121  L1 to ground 122 (I had a reading of 85 for a while may have been probe) L2 to ground 123.

I have been getting weird readings out of the panel when I tried to measure from the two hot wires as they entered the circuit breakers. One hot seemed to be at 210 and the other at 36.  So I disconnected the main input AC wires from the panels to measure them and got this L1- N 106 L2-N  105   LI-G 122 l2-G 123.

Anyone see anything here. I am going to switch back to the park we were at as I am more comfortable working on things there and will have access to their equipment.  So my next two steps were to plug in somewhere else and if I still have problems open the transfer switch. I never use the transfer switch but am wondering whether things got screwed up from moisture.   

 

Any help from anyone would be appreciated. I am not thinking clearly about this.

[Kirk W]

Pedestal readings sound good. I'm thinking that you either have a transfer device problem or an inverter problem. Have you checked the RV side of your transfer device to see if it is closing to the power cord? The normal position for it is to connect the power cord. You may also want to start the generator to see what changes. It is possible that your transfer device has failed or is closed to the generator and stays there.

[Lou Schneider]

The readings at the output of the transfer switch show you have a weak or non-existent neutral line at that point.  The purpose of the neutral is to keep the incoming 240 volts from the 50 amp connection evenly divided into two 120 volt circuits.  Without the neutral the voltages across each side of the incoming power will vary according to how much current is flowing on each side but will always sum up to 240 volts ... exactly what you're seeing.

Disconnecting the wires from the circuit breaker panel gave fairly normal readings because then you did not have current flowing.  It's the ratio of the currents in each line that create the voltage shift without a good neutral.

Check all of the connections at the transfer switch for looseness and corrosion, but the problem is probably inside the switch.

If Kirk's suggestion of starting the generator doesn't work, you could disconnect the incoming shore power line and the output line at the transfer switch and use wire nuts to connect the like colored wires together.  Line 1 to Line 1, Line 2 to Line 2, Neutral to Neutral and Ground to Ground.

 

[Daveh]

Yes thanks Kirk and Lou. I don't really need the transfer switch as I use Honda Generators into the main cord when I need too. So I think I will open up that box.

[Daveh]

Well, I directly wired the shore to the panel and bypassed the transfer switch. There was an area on a Line output that had over heated.  

However, the numbers I got after checking everything were exactly as I described above. The washer, fireplace and inverter all refuse the electric. When I put the breakers in again I had 220 on one line and 36 on the other even though they were each at 123 or to negative and about 106 to neutral when I reinserted the breakers.

Could this be something in the pedestal?  

[Ronbo]

220 on one line and 36 on the other indicate an open neutral. If you bypassed the transfer switch, the problem is prior to the switch. Did you check pedestal voltage with a load applied? If not, the problem may be with the pedestal. Do you have an EMS? If not you need one. You are putting 220volts on one leg. You may have damaged your inverter. I have the same inverter and had to have it repaired u dear warranty. It also was not transferring power nor charging. It takes a lot of tracking down to isolate the problem.

[Daveh]

Yes, I hope whatever it is the Magnum blocked it and hopefully did not fry. Inverter side still works.  I know our Splendide wash machine still works since I ran an extension cord to it from our Honda inverter. So it is somewhere in the front. I am suspicious of the new park but someone had used the electrical the day before. Heading to our ho,e park now where I have more resources. The UP of Mich is not where you want these problems.

[Ronbo]

If the inverter is bad and no longer under warranty, look at a hybrid inverter. You can now purchase one for about the original cost of your magnum. Then install an EMS. At my kids house we had bad wires to the property. My EMS saved me at least 10 times in 2weeks. Every time the wind would blow I would get high and low voltage because the neural would open. I have also found several pedestals at parks with open neutrals. They come out and put a meter on it without a load and declaim it good. They will tell you to turn off your EMS. Never do it. The only time I did was at the recommendation of a master electrician friend. I was on his property. It took out my original xantrex imberter. I then called the power company and they found a bad connection at transformer. Now it never turns off. Also once you get the inverter working, turn off the converter. It is not needed and I less you have replaced it, it will not properly charge lithiu batteries. Mine burnt up and I just removed it, never replaced it. 

[Daveh]

In another park and all is well. Fireplace, Magnum and washing machine all working. Need to check a few other things. Well I tore my transfer switch apart for nothing but I am thankful I got out of this without more damage. Knock on wood. Called the park we were staying at and told them they needed am electrician. We paid for 9 nights in advance but I told them I am not going back in that site until seen by an electrician. Thanks for all the advice folks. By the way Ron, I do have the hybrid Magnum.

[Kirk W]

5 hours ago, Daveh said:

Could this be something in the pedestal? 

Your move confirms what I'd have answered when you made this post. The neutral from the pedestal is what we call "floating." That is different from an open neutral in that the neutral is normally it the electrical center of the 240V giving 120V on each leg. If it floats that means it moves to one side or the other so that the 240V is no longer divided equally .

[Daveh]

Kirk. I told the park I thought they had an open neutral at the pedestal. Should I correct that terminology or should an electrician be able to find this. This is a brand new park and someone was there before us. Is this a miswire or something that can go bad? I don't know why I am the one that had all the problems as I don't have an EMS or anything sophisticated to find these problems. There was just clearly something wrong as the Charger, washer/dryer and fireplace did not like what they saw.  

[Daveh]

I just found this Kirk. Sound right?   

Impact of Floating Neutral in Power Distribution

JULY 28, 2012 130 COMMENTS

Introduction:

• If The Neutral Conductor opens, Break or Loose at either its source side (Distribution Transformer, Generator or at Load side (Distribution Panel of Consumer), the distribution system’s neutral conductor will “float” or lose its reference ground Point. The floating neutral condition can cause voltages to float to a maximum of its Phase volts RMS relative to ground, subjecting to its unbalancing load Condition.
•  Floating Neutral conditions in the power network have different impact depending on the type of Supply, Type of installation and Load balancing in the Distribution. Broken Neutral or Loose Neutral would damage to the connected Load or Create hazardous Touch Voltage at equipment body. Here We are trying to understand the Floating Neutral Condition in T-T distribution System.

What is Floating Neutral?

• If the Star Point of Unbalanced Load is not joined to the Star Point of its  Power Source (Distribution Transformer or Generator) then Phase voltage do not remain same across each phase but its vary according to the Unbalanced of the load.
• As the Potential of such an isolated Star Point or Neutral Point is always changing and not fixed so it’s called Floating Neutral.

[Kirk W]

That is what they are talking about.  And I would not bother to get back to the park as any good electrician will find the problem. If you were using one of the line monitor devices (Surge Guard or Progressive) it would have detected the problem and turned off the power. 

[Chalkie]

5 minutes ago, Daveh said:

 I don't know why I am the one that had all the problems as I don't have an EMS or anything sophisticated to find these problems. 

Not that this will solve your current issues but I think I would invest in that EMS. My Progressive caught and blocked the issue you describe in a campground. With the readings from the EMS the park had an electrician there amazingly fast to troubleshoot and correct the issue. Yes, a quality EMS will cost a bit, but well worth the potential costs it will protect against IMO.

[Daveh]

Yes, Kirk I was penny wise pound foolish on the EMS.  Already talked with my wife about getting one. I really think I would be happier with the portable pedestal ones. Those are not routinely ripped off, are they?

[Daveh]

Yes, Chalkie the EMS and Tireminder are always on my shopping list but I do not pull the trigger. Now I will on the EMS. I better get the Tireminder also or I will be writing about my blowout next week.

[Kirk W]

4 minutes ago, Daveh said:

Those are not routinely ripped off, are they?

I have used a Surge Guard portable with our last two RVs, a 50a version for the motorhome and now a 30a one for our travel trailer. I have never heard of one being stolen although there are devices available to lock them. Progressive used to sell a way to lock to the pedestal and we had a device from Surge Guard to lock it to our cord, but had issues with it and stopped using it. I bought my first one in 2003 and have now had one for 15 years.

[Chalkie]

1 minute ago, Daveh said:

 I better get the Tireminder also or I will be writing about my blowout next week.

🤣

[Mark and Dale Bruss]

For the trailer, we had an original Progressive EMS and the box was pretty big.  We used a cable lock but not because we were were worried about the EMS walking.  We use the cable lock to take the stress off of the power pole receptacle. 

12 years on the road and nothing has disappeared yet.

[fly2low]

I have a Progressive 50a hardwired system, tied in after the transfer switch.  Guards both pedestal source and generator - though probably not needed.   I was not worried about theft, just did not want to dig out the EMS every time I plugged in

[oldjohnt]

Hi Dave, sorry I got here late for responding to your shout out, I bought a house and have been too busy to keep up on here, but it sounds like you're on top of it,  so at this late point I will just address some "confusion" I so often find among lay persons.  

 So many don't understand the difference in bonding the Neutral and Ground Busses in the main service entrance panel    VERSUS   bonding of the Neutral to the NEC's "all readily available Grounding Electrodes" such as mother earth or referred to as "Earth Grounding" the Neutral.

Earth grounding of the Neutral BOTH HV Primary and LV secondary is for lightning and surge protection and to keep the grid at a common low voltage reference IE mother earth. A Neutral Buss to Ground Buss bond like at the main service entrance panel is so the safety equipment Grounding Conductors  (wired to Ground Buss) can provide a dedicated low resistance return current path for FAULT CURRENT ..........

 If you notice in the article you cited they spoke of

12 hours ago, Daveh said:

The floating neutral condition can cause voltages to float to a maximum of its Phase volts RMS relative to ground

VOLTAGE RELATIVE TO  GROUND (if you mean earth ground)   is  NOTTTTTTTTTT necessarily the same as voltage L1 or L2 to Neutral, but if the Neutral is in the center of the transformer (DUH) its still 120 on either leg TO NEUTRAL. Right at the service entrance panel where Ground and Neutral Busses are bonded, voltage should be near the same from L1 or L2 to the Ground Buss or Neutral Buss but if that Neutral is open there's no center tap of the transformer available and half L1 to L2  reference point.......

SOOOOOOOOOOOOO in a 120/240 volt Single Phase Three Wire residential service  L1 & L2 are across the 240 volt output of the transformers LV Secondary while the center of that transformer winding is tapped yielding 120 L1 to the center tapped Neutral or 120 L2 to the same center tapped Neutral. Now if that Neutral is open you still have 240 L1 to L2 but if one 120 volt load fed off L1 and another 120 volt load fed off L2  ARE  NOT THE SAME RESISTANCE and on and current flows VOLTAGES WILL BE DIFFERENT one higher one lower then 120 and you fry things !!!!!!!!!!!!!  BUTTTTTTTTTTT that occurs UNDER LOAD. If there's no current flow you don't get unbalanced voltage, its still 120 to the center of the transformer (Neutral) but if its open YOU CANT GET THERE. With the Neutral in place you're gonna be locked down to 120 on either leg (its 1/2 of 240) relative to Neutral so there's no risk.   

 In a 50 amp RV if you see different voltages L1 or L2 when current is flowing I SUSPECT AN OPEN OR LOOSE/RESISTIVE NEUTRAL. NOTE it (where you're measuring voltage) also depends on current flow and where the Neutral is open, is it at the Pedestal of from Pedestal to RV or in the RV panel, and again no harm is done until loads are applied and current flows.

 The thing is people start talking about Line to Neutral voltages and them being different L1 or L2  HOWEVER if there's so real connected Neutral its like the bridge to nowhere and just what is it they are measuring and to where?????  Depending on the type and quality of the meter and if there are any current drawing loads YOU MAY GET ABOUT ANYTHING but if there is a Neutral and all connections are good its 1/2 of that 240 volt transformer 120 volts locked in.

 Any even half competent electrician can find an open or loose Neutral and as the problem stopped when you changed parks I suspect it may have been the parks problem not yours, but cant say for sure sitting here. I would suggest a quality EMS or at the least monitoring and checking voltages for proper connections.    

Hope this theory helps you understand your situation

John T Longggggggggg retired electrical power distribution design engineer and rustyyyyyyyyy on this stuff SO NO WARRANTY but believe the above still remains true ????

  

 

[Daveh]

Thank you very much John. I have read it three times now and it is sinking in. 

So this open or floating neutral problem could be further upstream in the park, or at the pedestal, or in the wiring entering my coach to the panel, right?    But what happens if it is further downstream like in a circuit coming off the panel in the RV? If there was a loose or unconnected neutral wire in one of  my lights, or the toaster, would that impact the whole coach and give me weird readings at the panel. Everything is good at this new location I am just wondering if the problem is, or was, with my coach would I have ended up looking at every outlet or is the inquiry limited to the panel------out.  

 

[Kirk W]

59 minutes ago, Daveh said:

If there was a loose or unconnected neutral wire in one of  my lights, or the toaster, would that impact the whole coach and give me weird readings at the panel.

Your power distribution panel has two separate bars in it, one supplied by L1 and the other by L2. The 120V circuit breakers tie from one bar to the neutral but are not impacted by the other leg. If the neutral to your toaster should open the toaster does not work as the return has to be via that neutral. In a 240 volt circuit, the load is between L1 and L2 and effectively sees +120v and -120v giving the total of 240. For a floating ground to happen you have to have all three parts. Once your power arrives at the distribution panel the loads no longer see both L1 and L2 so a floating ground problem does not have that same effect and really isn't possible. It would be very possible to make this far more complicated, but to keep things simple, just realize that a floating ground will never happen in your RV's 120V circuits. A floating ground basically occurs when the neutral is in effect not dividing the 240V supply in the center.  For this same reason, a floating ground doesn't happen in the same way in a 30a RV either but shows up as a bad voltage.

As to your lights, they are supplied by 12V-DC power from your converter or battery so have no impact at all on your shore power. 

 

 

[Daveh]

1 minute ago, Kirk Wood said:

 It would be very possible to make this far more complicated....... 

 

 

😂  Thank you for having mercy on me Kirk. That is what I thought just making sure.

[oldjohnt]

7 hours ago, Daveh said:

  But what happens if it is further downstream like in a circuit coming off the panel in the RV? If there was a loose or unconnected neutral wire in one of  my lights, or the toaster, would that impact the whole coach and give me weird readings at the panel.

 Good questions Dave, shows you're actually reading all this stuff LOL and it appears my discussion is sinking in yayyyyyyyyyyy. Let me try to explain a bit further and answer your new specific questions.

 1) You ask " but what happens ... like in a circuit coming off the panel in the RV"

 ANSWER if the Neutral comes off the individual branch circuit to say a light or toaster IT DOESNT WORK. It takes two wires Hot and Neutral having 120 volts across them to power a 120 volt appliance. Just a single wire, be it the Hot or the Neutral, doesn't suffice and I'm  sure you already understand that.

 Of course, if the Neutral comes off BEFORE it even gets to your panel:

 A) If its a 30 amp 120 volt RV   nothing works  WELL DUH

 If its a 50 amp  120/240 volt RV absent a Neutral and loads are turned on fed from BOTH (L1 & L2) and they aren't the same resistance, one is gonna see high voltage the other one low voltage and things get FRIED !!!!!!!!!

 2) You ask  " would that impact the whole coach and give me weird readings at the panel"

  ANSWER

  A) If a Neutral to only a single branch circuit came off to your lights or toaster NO that doesn't impact the whole coach.

    If a Neutral came off BEFORE the panel YES that impacts the entire coach, see the above, 30 amp and 50 amp RV would be different.

 

Some of the terminology above is a bit fast n loose and inconsistent regarding the terms GROUND   NEUTRAL   LOOSE  FLOATING  so let me try to explain it using state of the art and NEC terminology used by electricians and electrical engineers.

1) Ground is NOTTTTTTTTTTTTTTTTT the same as Neutral and Earth Grounding the Neutral is NOTTTTTTTTTTT the same as Neutral Ground BONDING.   

2) Some Generators utilize a FLOATING  Neutral while others use a BONDED Neutral, although the utility electrical service like where your RV is plugged  uses a BONDED Neutral and the Neutral is also EARTH GROUNDED for surge and lightning protection and to keep the grid at one common low voltage reference IE Mother Earth.

3) Wayyyyyyyyy back when I practiced and attended NEC Seminars here's the terminology used............

  a) If the Neutral becomes totally disconnected THATS AN OPEN NEUTRAL

  b) If the Neutral comes loose yet still conductive via high resistance carbon THATS A LOOSE OR RESISTIVE NEUTRAL

   c) As the Utility DOES NOT utilize a FLOATING NEUTRAL (Its Bonded to the Ground Buss and earth grounded remember) the Neutral UNLIKE a floating Neutral Genset, is Bonded yet can still become loose/resistive or totally open. 

 Floating Neutral means its NOT Bonded, while it can be bonded yet loose and resistive in which case THE VOLTAGE is what's gonna "float" subject to current flow and the amount of resistance in the loose connection.........   

 

As well posted above it would be very possible to make this far more complicated, but it need not be if you just remember the basics of 120/240 volt Single Phase Three Wire Service.

The LV Secondary transformer is 240 volts line to line HOWEVER if you tap it in the dead center (Neutral) its ONLY 120 Volts from either end to the middle. A 120/240 volt panel has