Rv power source advice/ help Inverter

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  #1  
Old 05-13-17, 10:03 PM
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Rv power source advice/ help Inverter

Ill get to basic over view so most of you understand what Im asking.. If im wrong on statements please let me know.

My RV.

Rv electrical panel is really a sub panel. N/G are separate.Floating?

When I plug the RV into the campgrounds pedestal I get the bond there. OK. All Good.

When I plug the RV into my generator, I assume it can go either way. The gen can be bonded or not depending on who you talk to.

( I leave both my generators when using them for the RV as floats or unbonded N/G. I think this is safer but just my opinion as I believe there will be no path to ground to come back and shock me.)

Some RV's need this bond for the RV to poewer up. So many Rv'ers install a N/G plug in an open outlet to overcome this.

Concern,

Now I plan on putting a inverter in the camper. This inverter has a floating neutral. The ground plug is attached to the chassis of inverter. I tested with continuity.

Instructions say to run 10 gauge from grounding lug on case to trailers frame. OK there.

I plan on taking the trailers power cord and plugging it into the inverter to power my camper. ( Its 1100 watts.)


I asked the question to the manufacture if I should bond this inverter or not.

Here are the questions and response,


HI,

Possibly you can help me with a technical question.

I have a Krieger 1100 watt inverter. I will be installing this in my rv travel trailer.

The travel trailer is basically a sub panel. So when I plug into the camp grounds pedestal I get the bond at the service entrance.

This would also stand true I assume for my 2800 watt gas generator. When I plug the RV to that I get the bond from the generator. This generator is bonded neutral/ground.

I notice your invertor has an open neutral from my test light. I will
be running a ground wire from the back of the unit to the trailers frame.

What I am going to do is essentially plug the RV into this invertor to power it. This will power all my outlets in the trailer. I will be turning off the charging circuit so there is no endless loop going on.

I am not sure if I should bond the N/G in the krieger invertor. I would plug a n/g plug into the extra outlet to accomplish this.

1. Should I leave this as an open neutral unit or make N/G plug to
bond the neutral and ground? ( Attached is an image of said plug) 2.
What gauge wire should run from grounding terminal in back of unit to
frame of trailer? ( I was going to use 6 gauge)

I hope you understand this and can help me.


Thanks

Mike NJ



HI Mike,

Thank you for the provided information about your application. We recommend using only the hot and neutral on the plug only and do not use the AC ground when connecting the inverter to a breaker panel box. You should use #10 gauge cable when connecting the ground chassis located on the back of the inverter to the frame of the trailer.


Customer Support
Krieger Manufacturing


Ok just to be clear in laymans terms,

So you recommend just plugging the RV into the krieger inverters outlet, with no modification to the neutral/ground, even though it will show as open?

Yes I will use 10 gauge or better for the chassis ground.

Also would you be able to supply a schematic for this 1100 watt inverter?

Thank you for your time. Its much appreciated......

Regards

Mike NJ


The modified wave inverter shows an open or floating ground compared to power received from your AC wall outlets. This results in a incompatibility when connecting to a breaker panel box. The best way is to just use the hot and neutral legs on the inverter's AC outlet and do not use the ground connection when connecting to a breaker panel. We still recommend grounding the inverter by connecting the 10 AWG cable to the ground chassis terminal located on the back of the inverter. You can consult with a qualified electrician for proper installation if needed. We do not provide diagrams, schematics, or a parts list to any of our products due to proprietary reasons.


Customer Support
Krieger Manufacturing
Does this sound correct that he suggests not connecting the ground wire in the adapter I make to plug into the inverter? ( Trailer has 30 amp TT plug... Inverter is 20 amp outlet. I need to make a dog bone.)

Im pretty sure the ground wire in the travel trailer panel goes to the frame of the camper. and grounding the chassis of inverter to the frame of trailer is the same.

Why would he suggest this? Do you think he may not understand how RV wiring works or is it I who am missing something?

Also I will not be bonding the inverter and will leave it as an open neutral.
 
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Old 05-14-17, 05:12 PM
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No one? Was my post too long?

Well I took my kohler 2.8I generator and removed the bond today. I also removed the GFI outlet . But I am thinking maybe I could of left the GFI.. Its not required now that I unbonded the generator..

I just acquired this gen. I ran it from the 30 amp twist lock to try it out to my homes transfer switch..

The well pump motor starts slow/ Is this normal with an inverter gen? Pump motor spins and slowly ramps up then starts.

Gen with GFI


I changed outlet, removed bond, and covered GFi lablel with floating neutral label
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  #3  
Old 05-14-17, 06:04 PM
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Hi, Mike.

I get the feeling that you are not familiar with the reason why commercial power systems have a neutral-ground bond. With only one exception that I can think of at the moment, the purpose of the neutral-ground bond is ONLY to facilitate the fuse or circuit breaker on a branch circuit to pop/trip when a "hot" to equipment ground occurs.

The one exception is when a flame rectification circuit is used in a gas-fired device to prove the existence of the flame. For this purpose the "ground" is required to complete the circuit. It is allowed because the current is limited to mere micro-amperes.

With your inverter (or the not-bonded generator) neither of the two power wires (conductors) are connected to the earth or some specified "ground" point. That means that there is no reference from either wire to the earth so no real current flow will take place. This also means that there is no reference between either wire and any "grounded" metallic part of any appliance...in other words, there is no real shock hazard under normal circumstances. There can be no "ground faults" (line-to-ground faults) with this system simply because the "ground" never enters the picture.

Of course, without one line "grounded" (bonded to earth) the terms "hot" and "neutral" are meaningless. Both conductors are "hot" in reference to the other. The problems only arise when you have a defective device that has one conductor inadvertently connected to the frame of the device and even then it only becomes a hazard when a second device with a similar fault, but with the other conductor is also connected. In this scenario the cases of the two devices would each be connected to opposite wires and then a very real shock hazard exists if a person were to touch both cases.

I agree with the manufacturer of the inverter, do NOT connect the equipment grounding conductor (the green wire) when connecting the inverter output to the circuit breaker panel in the trailer.

[The term "sub-panel" is incorrect, that term does not even exist within the NEC. It is simply a circuit breaker panel that does not contain a neutral-to-earth (or equipment ground) bond.]


As for the well pump starting slowly on the new inverter generator...more likely that the instantaneous overload output of the inverter is simply not high enough to get that pump motor running in the usual time. Some inverter generators are conservatively rated (have more surge output) than others. I don't know that it would actually harm anything as long as it starts reliably but if it takes too long it could conceivably burn out the inverter or the pump motor.
 
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Old 05-14-17, 07:01 PM
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I agree with the manufacturer of the inverter, do NOT connect the equipment grounding conductor (the green wire) when connecting the inverter output to the circuit breaker panel in the trailer.
Thank you Joel...

Is the reasoning of not hooking up the ground wire from the output of inverter, to the umbilical cord of the rv, because the manufactured states to ground the case of inverter to trailer frame?

I have no problem doing it but just wondering the reason one way or the other.

Why is this any different then running the RV from the generator with no bond. The ground pin in gen outlets tie to frame of gen. So woulnt the gen case be tied to the RV frame when pluged in?

The panel ground in the RV is tied to the frame of TT I would think...
 

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Old 05-14-17, 07:25 PM
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I get the feeling that you are not familiar with the reason why commercial power systems have a neutral-ground bond.
Osha I believe. Not the NEC.?

What I know.

Any gen thats bonded requires GFI.
Seperately derived gen needs bond
3 wire gens need bond ( Although my old colman was a floating nuetral 3 wire from factory. Probably old code and its not like that anymore)

GFI gen exceptions are

gen must be 2 wire single phase
Gen must be under 5000 watts
circuit wires must not connect to frame, case or grounded surface ( Floating)

probably more items but cant think..
 
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Old 05-14-17, 11:36 PM
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One more odd thing I noticed on the gen in the pics below.

There are no breakers.

On an inverter generator is this done by going into overload? Mechanical breakers are not needed?

I wouldn't think that the GFI I removed would be a breaker because the twist lock is not a GFI or was it tied the the duplex GFI,
 
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Old 06-01-17, 08:54 PM
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Well almost done. Got the solar charger and inverter in... As I stated Ill assume not to hook up the ground wire on the outlet I install..

This was a PITA and time consuming.. Doing it for myself is one thing... If I had to do this for a living I would need to get paid big bucks...

Any suggestions?

Yes I know I should of put the fuses closer to the batterys, but I was afraid of what the outside weather would do to the ANL's



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Old 06-02-17, 01:27 AM
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Hi, Mike. I've been thinking about all of this for some time. I'll try to hit on the points you raise with my opinions. Remember, these are my opinions and while I think they are based in logic they are not necessarily compliant with either the NEC or OSHA codes.

First, the metallic cases of all electrical items that could, under fault condition, become energized are best bonded together. This is to keep them all at the same potential voltage and eliminate the risk of shock. This is the best reason I can come up with for running the wire from the inverter grounding terminal to the camper frame.

While I can't say for ALL inverter generators, my Yamaha does not have a conventional circuit breaker for the AC output. Instead it has an inverter protection circuit that will disconnect the inverter output on either short circuit or overload. It is necessary to stop the engine completely in order to reset this protection circuit.

The fuses will protect no matter where they are in the circuit. Placing them closer to the battery DOES offer more protection IF the wiring is located where it is subject to physical damage.


As for the big bucks...back in about 2002 I was making six figures, barely. Quite honestly, I would rather be doing electrical than plumbing work any day.
 
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Old 06-02-17, 11:22 AM
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Thanks Joel..

Upon testing today and trying to figure the reason to lift the ground wire I came to this conclusion..

Maybe you can help with my findings..

Here is what I know

1.As I said this is a floating inverter. The ground is connected to the chassis of the inverter.
2. I attached 8 wire from chassis to TT frame.
3. It would seem this is a 1/2 voltage inverter. 60v/60v on each leg..I dont have a true RMS meter to test .
4. When I plug the camper in and test an outlet with polarity test I get all connections correct. ( Odd because its floating. It should not read this)


5. It would seem on these 60v/60v type inverters the DC negative may be tied to the AC neutral/common somehow..

I believe #5 is why the manufacturer is telling me to lift the ground wire. To insure this inverter floats.

Because as I state above if I dont lift the ground the test plug shows correct polarity's/wiring. And to repeat is odd because if I plug the tester directly into the inverter it test open neutral.

I verified with my multi-meter that the ground is indeed not tied together in the inverter.

I did test the negative DC terminal to the rear ground lug and got continuity.

Does this make sense?
 
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Old 06-02-17, 12:06 PM
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Well just did the test with the ground lifted.

Polarity tester shows wiring correct whether ground lifted or not. No difference either way..

I assume when I connected the case of the inverter to the travel trailers chassis, for what ever reason makes the polarity reader rear correct.

I assume if I disconnect that wire from the travel trailer frame to the inverter chassis it will then read floating..

So what do I do?

Follow the advice of krieger and leave the ground lifted?




HI,

Possibly you can help me with a technical question.

I have a Krieger 1100 watt inverter. I will be installing this in my rv travel trailer.

The travel trailer is basically a sub panel. So when I plug into the camp grounds pedestal I get the bond at the service entrance.

This would also stand true I assume for my 2800 watt gas generator. When I plug the RV to that I get the bond from the generator. This generator is bonded neutral/ground.

I notice your invertor has an open neutral from my test light. I will
be running a ground wire from the back of the unit to the trailers frame.

What I am going to do is essentially plug the RV into this invertor to power it. This will power all my outlets in the trailer. I will be turning off the charging circuit so there is no endless loop going on.

I am not sure if I should bond the N/G in the krieger invertor. I would plug a n/g plug into the extra outlet to accomplish this.

1. Should I leave this as an open neutral unit or make N/G plug to
bond the neutral and ground? ( Attached is an image of said plug) 2.
What gauge wire should run from grounding terminal in back of unit to
frame of trailer? ( I was going to use 6 gauge)

I hope you understand this and can help me.


Thanks

Mike NJ


HI Mike,

Thank you for the provided information about your application. We recommend using only the hot and neutral on the plug only and do not use the AC ground when connecting the inverter to a breaker panel box. You should use #10 gauge cable when connecting the ground chassis located on the back of the inverter to the frame of the trailer.


Customer Support
Krieger Manufacturing

Ok just to be clear in laymans terms,

So you recommend just plugging the RV into the krieger inverters outlet, with no modification to the neutral/ground, even though it will show as open?

Yes I will use 10 gauge or better for the chassis ground.

Also would you be able to supply a schematic for this 1100 watt inverter?

Thank you for your time. Its much appreciated......

Regards

Mike NJ

The modified wave inverter shows an open or floating ground compared to power received from your AC wall outlets. This results in a incompatibility when connecting to a breaker panel box. The best way is to just use the hot and neutral legs on the inverter's AC outlet and do not use the ground connection when connecting to a breaker panel. We still recommend grounding the inverter by connecting the 10 AWG cable to the ground chassis terminal located on the back of the inverter. You can consult with a qualified electrician for proper installation if needed. We do not provide diagrams, schematics, or a parts list to any of our products due to proprietary reasons.


Customer Support
Krieger Manufacturing
 
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Old 06-02-17, 01:48 PM
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OK as it stands now,


Im relying on you Joel for any informative answer on what to do.. It seems the electricians on this site do not want to comment..

Possibly its not widely understood and its a gray area for some..

Basically the question is should I lift the ground wire or not?

Ill take pics later when Im done or tomorrow..

Right know I have it with the ground lifted. I can easily connect the ground if needed..

The ground is lifted inside the TT 30 amp plug I installed external to the camper..


If there are any tests you need from the inverter let me know..


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Old 06-02-17, 02:08 PM
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Heres a similar inverterwith better instructions page 13..

http://gpelectric.com/files/gpelectr...HD-3000_vB.pdf


A camper is not a positive ground system..

Do not install the power inverter in a positive ground DC system. A
positive ground DC system has the positive terminal of the battery
connected to the chassis of the vehicle or to a grounding point.
Also.


This inverter cannot supply power to any AC distribution wiring or AC
loads in which the neutral and ground are connected (bonded). Doing so
will destroy the unit and void the warranty. If you do not understand
neutral to ground bonding then please have a professional install your
system for you. See “Grounding” for more information.

The power inverter has a lug on the rear panel: "Chassis Ground." This is to connect the
chassis of the power inverter to a grounding point.
The power inverter grounding point will vary depending on where the power inverter is
installed. In a vehicle, connect the chassis ground to the chassis of the vehicle. In a boat,
connect to the boat's grounding systems. In a fixed location, connect the chassis ground
lug to earth.
The neutral (common) conductor of the power inverter AC output circuit is not bonded to
the chassis ground. Therefore, when the chassis is connected to ground, the neutral
conductor will not be grounded.
At no point should the chassis ground and the neutral conductor of the inverter be
bonded. Bonding the chassis ground and the neutral conductor of the inverter or
connecting the inverter to household or recreational AC distribution wiring will damage the
unit and void the warranty.
As per the national electrical code, electrical panels in mobile applications (boats, RVs
etc.) must not have a neutral to ground bond.

Oh end even better this describes my inverter better. From samlex..


http://www.samlexamerica.com/documen...-1216-Hrez.pdf


The metal chassis of the inverter and the Grounding Terminal of the NEMA5-15R outlet(s)
are internally bonded (connected) to the Negative DC Input Terminal on the inverter. In a
vehicle / boat, the Negative Terminal of the battery is bonded to vehicle chassis / boat’s hull.
Hence, the metal chassis of the inverter and the AC loads will be automatically grounded
(bonded to the vehicle chassis / boat’s hull).
2. Please ensure that the Negative DC Input Terminal on the inverter or the Battery Negative
Terminal on the battery itself is bonded to Earth Ground WHEN THE INVERTER IS USED ON
LAND.
3. The Line and Neutral Terminals of the NEMA5-15R AC outlets are isolated from its Grounding
Terminal. Thus, the metal chassis of the AC loads and the metal chassis of the inverter
will also be isolated from the Line and Neutral slots of the AC outlets. The Grounding
Terminal of the AC outlet is connected to the input section of the Electronic Ground Fault
Protection Circuit on the Power Circuit Board. Due to the above implementation, the voltage
on the Neutral and Line Terminals of the AC outlet with respect to the chassis of the
inverter / chassis of the AC loads will be pulsing DC voltage with average DC value of up to
50V (will read 75 VAC on AC scale of the Voltmeter because of pulsing nature of DC voltage).
DO NOT TOUCH THE NEUTRAL TERMINAL / NEUTRAL CONDUCTORS!
4. Do not connect to AC distribution wiring where the Neutral is bonded to Ground. The
inverter will see this as abnormal condition of Ground Fault and will shut down.
5. Do not use with Positive Grounded Electrical Systems (the majority of modern automobiles,
RVs, trucks and boats use Negative Grounded Electrical Systems).
6. Observe correct polarity when connecting the DC input terminals of the inverter to the
battery. Connect Positive of the battery to the Positive input connector of the inverter and
the Negative of the battery to the Negative input terminal of the inverter. Reverse polarity
connection will result in a blown fuse and may cause permanent damage to the inverter.
Damage due to reverse polarity is not covered under warranty.
7. This inverter will not operate high wattage appliances that exceed the output power limit
or the surge power limit.
8. Do not operate this inverter if it is wet.
9. Do not install in engine compartment – please install in a well-ventilated area.
10. This inverter is not tested for use with medical devices.
 
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Old 06-02-17, 06:06 PM
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Well, Mike, that sounds pretty cut and dried. It is essentially the same as I was going to write, that there is no good reason to "bond" the so-called "neutral" conductor to the equipment grounding conductor.

I think one reason you are somewhat confused is that the term "neutral is completely meaningless with the inverter. A neutral conductor ONLY exists when there are multiple voltages such as the standard residential service of 240/120 volts delivered on three wires. The neutral is simply the mid-point of the two coils in series in the transformer (could be a generator) supplying the power. Since the inverter has ONLY one voltage there is NO neutral, both leads are hot and neither of them is referenced to "ground", whatever the definition of ground.

So, the "shore power" supply to the campers SHOULD have the equipment grounding conductor connected and travel through the shore power/ inverter transfer switch to the circuit breaker panel. The CB panel should NOT have the neutral bonded to the equipment ground (or enclosure) in any manner. The chassis ground of the inverter should also be connected to the CB panel equipment ground bus.
 
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Old 06-02-17, 06:27 PM
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So, the "shore power" supply to the campers SHOULD have the equipment grounding conductor connected and travel through the shore power/ inverter transfer switch to the circuit breaker panel. The CB panel should NOT have the neutral bonded to the equipment ground (or enclosure) in any manner. The chassis ground of the inverter should also be connected to the CB panel equipment ground bus.
In laymens terms I should hook the ground wire up?

The chassis ground of inverter is hooked to the travel trailers metal frame.. The trailers panels grounds I believe all tie to the trailer frame anyways...

I thanks you for helping me..
 
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Old 06-02-17, 06:35 PM
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In laymens terms I should hook the ground wire up?
If you mean the ground wire (equipment ground, green wire) in the shore power inlet the answer is yes. I think that is different from what I originally stated but I thought that you were asking about a neutral-to-ground bond. Absolutely NO bonding of either of the power leads from the inverter.
 
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Old 06-02-17, 06:56 PM
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Why do you think the manufacturer stated this?


We recommend using only the hot and neutral on the plug only and do not use the AC ground when connecting the inverter to a breaker panel box.
I believe he may think its a residential panel and dont know the G/N in a travel trailer are not connected.

Would that assumption be true?

So just say I was going to hook up this inverter to my home panel. It would make sense to lift the ground wire, correct?
 
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Old 06-02-17, 07:25 PM
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I assume (always a bad idea but in this case I think I am correct) the the ground terminal on the inverter output receptacle is simply connected to the chassis ground. It would not make any difference it you used the "equipment" ground or not.

HOWEVER, if you did want to connect the inverter to your home panel you WOULD have to remove the neutral/ground bond (often a screw through the neutral bus into the enclosure AND the "grounding electrode conductor (GEC) the wire that goes to the ground rod and/or metallic water piping. FGurther, you would have to remove ALL the bare copper equipment grounds (or green wires) from the neutral bus as well.

Bottom line, don't even think about connecting the inverter to your house panel.
 
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Old 06-02-17, 07:52 PM
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Bottom line, don't even think about connecting the inverter to your house panel.
LOL...


the ground terminal on the inverter output receptacle is simply connected to the chassis ground.
Yes it is.


It would not make any difference it you used the "equipment" ground or not.
So it dont matter if I leave it lifted or not..

I would prefer to just connected but I have in my head a term " Ground Loop" I may of heard a long time ago. AFAIK a ground loop is bad?

And it would seem that but I probably know better and its not a loop per se'
 
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Old 06-02-17, 09:41 PM
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I don't think you need to worry about ground loops. They usually only affect small signals such as from microphones and instrumentation systems.

The grounding conductor from the shore power should be carried through to the CB panel so when you are on shore power everything is properly bonded and grounded. This will have no effect when on inverter power, assuming, of course that you have a proper selector switch that allows only ONE source of power at a time.
 
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Old 06-02-17, 10:13 PM
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Does this make sense with what I have and what im doing? ( Ooops ill try to make it bigger..)
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Old 06-02-17, 10:18 PM
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.




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Old 06-02-17, 10:30 PM
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So as you see when I camp if I go to a rv park with camp ground electric I plug in normally.

If I am boondocking in the woods or mountains and the RV park has no electric available I will take my trailers umbilical cord and plug it into the inverter I installed.

The ext cord I made is plugged into the inverter, runs through the floor and under the trailer where I installed a travel trailer outlet with the ground lifted.


[ATTACH=CONFIG]81494[/ATTACH]

[ATTACH=CONFIG]81495[/ATTACH]




( An electrician im not... I just want to make sure my family or myself are not going to get electrocuted.)

Sry for beating a dead horse...
 

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Old 06-03-17, 08:08 AM
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Okay, I see what you are doing. At first I thought you had a transfer switch to power the circuit breaker panel from either the shore power OR the inverter. Now I see that you merely plug the inverter output into the shore power inlet.

It is a good system as it precludes powering the panel from both sources simultaneously. The only caveat, which has already been beat to death, is that the panel may NOT have any places where the equipment grounding conductors are connected to the main power.

Oh, that "receptacle" on the end of the inverter cable that plugs into the shore power cable is properly called a "connector".
 
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Old 06-03-17, 09:49 AM
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the panel may NOT have any places where the equipment grounding conductors are connected to the main power.
Whats that mean Joel?

The main panel in an RV have the neutrals and grounds separate. I believe the grounds just tie to the RV's metal trailer frame...

And with the new found info I show should I keep the ground lifted?
 
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Old 06-03-17, 03:16 PM
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Whats that mean Joel?
Exactly how it reads, do NOT have any kind of "bond" between the power wires (white and black) and the bare or green grounding wires.

And with the new found info I show should I keep the ground lifted?
NO. The grounding (equipment grounding conductor) is to cause a high current to flow UNDER FAULT CONDITIONS and trip the RV park circuit breaker. Now the chances of a fault are slim but it could happen, especially if you get an energetic raccoon or beaver chewing on the cables under the trailer.
 
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Old 06-03-17, 04:47 PM
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A
nd with the new found info I show should I keep the ground lifted?
NO. The grounding (equipment grounding conductor) is to cause a high current to flow UNDER FAULT CONDITIONS and trip the RV park circuit breaker. Now the chances of a fault are slim but it could happen, especially if you get an energetic raccoon or beaver chewing on the cables under the trailer
.

Im talking about the ground wire I lifted from the corb I made coming from the inverter, to the outlet I installed under the trailer..

I decided to connect that ground wire on the plug I made. I did this to test the GFI's in the camper when running off the inverter.

I have a polarity tester with a GFI trip button.

When the camper is plugged into the homes electric GFI's work fine. When testing GFI's when plugged into the inverter they will not trip. So I hooked up the ground wire in the plug and they still dont trip..


I assume GFI's do not work with modified sine wave inverters... Or the GFI's dont work without a bond..
 
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Old 06-04-17, 01:02 AM
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Mike, you are really overthinking this. You state that testing with a polarity tester / GFCI tester did NOT trip the GFCI. Did you try using the test button on the GFCI itself?

With a stand-alone GFCI tester when you push the button it inserts a high resistance between the black wire and the ground wire. This causes a small current (6 mA as I recall) to flow on the black wire but no current to flow on the white wire and sensing this difference the circuit trips the GFCI.

However, the inverter is NOT referenced to the earth (ground) and so no current will flow when using a stand-alone tester. That the GFCI failed to trip when using the stand-alone tester is a good sign.

Leave the ground conductor connected.
 
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Old 06-04-17, 01:31 AM
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Mike, you are really overthinking this. You state that testing with a polarity tester / GFCI tester did NOT trip the GFCI. Did you try using the test button on the GFCI itself?
Thats what I do ...over think..Its my nature from all those years at lucent technologies working with the EE's and PHd's...lol..

The polarity tester with the gfi button did not trip the gfi with ground wire connected or disconnected. It didnt make a difference.

It will trip the gfi if I plug the camper into my homes electrical system.

Yes I did also push the gfi outlet manualy also in the camper to see if it works. It does.

That the GFCI failed to trip when using the stand-alone tester is a good sign.

Leave the ground conductor connected.
Thank you Joel. I will perform testing again tomorrow just to verify.

What im trying to do is just understand it..Like you say its a good thing that the gfi didn't trip... I dont know why thats a good thing when its supposed to trip with that tester.. It trips when I am plugged into the homes circuit..



But I trust your wisdom.

Im not sure if im right on this but there are two thoughts about bonding and not bonding in the electrical world. And depending on who you talk to , and regardless of the NEC , no path to ground is supposed to be safer.

Im not that smart when it comes to electric.

By the way how are your hands doing? I dont mean to make you type so much..
 
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Old 06-04-17, 01:48 AM
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Electrical systems in the early part of the twentieth century were not bonded. They used fuses in both lines. By and large in marine practice , at least some forty years ago they did not bond. They DID have "ground fault indicator lamps however that would show the presence of inadvertent grounds. A single ground fault is generally not a serious condition but a second one IS.

Grid-supplied electrical systems are grounded/bonded for a few reasons, not the least to provide a "reference" between the ungrounded conductors and the earth. There are a few other reasons and it can become pretty overwhelming to try to digest it all. But in the case of a stand-alone system, your generator or your inverter, there are few good reasons in favor of bonding.

Your problems or questions are coming about because you have BOTH systems on the trailer, grid-supplied when plugged in at the campground (or at home) and the inverter. Confusion IS normal.

My hands have been okay the last few days but now I have other problems. I'm pretty sure I passed a kidney stone Thursday, felt enough better on Friday to allow me to make a trip to Seattle to pick of some project materials but then Saturday I just felt like crap. I'm one big mass of pain, legs, back, neck headaches and pretty much don't feel like moving. I have to pee every couple of hours and I haven't even been to the garage since Wednesday.

Going to fill my water jug and go to bed now.
 
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