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Old 01-13-2020, 07:42 PM   #1
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Default Roadtrek RS Adventurous Inverter Upgrade

My 2006 RT Adventurous has a 750W Tripplite Inverter/Charger, which produces modified sine wave 120 VAC, which is delivered only to the galley and TV/audio outlets. These outlets also receive power when shore power or generator are connected.

The modified sine wave 120 VAC is not tolerated by modern appliances, so despite being well below the 750W rating of the inverter, trip off.

I am thinking a pure sine wave inverter will allow operation of newer appliances. My plan is to set the Tripplite to "Charge Only", and install a new 1000 or 1500W pure sine wave inverter supplied from the outlet side of the 12V relay and fed into the 120V Inverter Output receptacle.

I would note for full context that the coach batteries have been upgraded to two 6V x 235 Ah, and that a Victron Battery monitor has been added. Although the RT is also equipped with a generator, my primary objective in upgrading the inverter is to be able to make coffee or otherwise use electricity if I am without shore power and camping where generator run-times are limited.

With the extra capacity, I am also thinking the new inverter could connect to the entire AC bus. But that raises two questions, neither of which are answered by the electrical distribution diagram or the RT manual.

1. Since the two outlets powered by the inverter are also powered up when shore tie or generator are connected, what segregates the other outlets to prevent their being fed while operating just on the inverter? I am thinking diodes but am not sure where they are located.

2. If the inverter is connected to the entire 120V bus, how do I (automatically) prevent inverted 120V power being sent to the Tripplite charger and back to the battery, which would result in accelerated battery drain? A relay cutout might be one way to do this.

For context, I have already upgraded my batteries to provide 235 Ah, and have installed a battery monitoring system, and am equipped with a generator. My main objective is to support coffee maker and other devices in situations such as camping without shore tie when generator run times are limited.
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Old 01-14-2020, 11:58 AM   #2
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Maybe download and read through the manual or user guide for this Automatic Transfer Switch - Inline Transfer Relay


I think it will answer a lot of your questions as to how to safely do what you want.


Some inverters will have a built-in Automatic Transfer Switch. I think it'll all become much clearer as soon as you learn just a bit more about the function and use of that type of switch.
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Old 01-14-2020, 02:09 PM   #3
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Originally Posted by engnrsrule View Post
My 2006 RT Adventurous has a 750W Tripplite Inverter/Charger, which produces modified sine wave 120 VAC, which is delivered only to the galley and TV/audio outlets. These outlets also receive power when shore power or generator are connected.

The modified sine wave 120 VAC is not tolerated by modern appliances, so despite being well below the 750W rating of the inverter, trip off.

I am thinking a pure sine wave inverter will allow operation of newer appliances. My plan is to set the Tripplite to "Charge Only", and install a new 1000 or 1500W pure sine wave inverter supplied from the outlet side of the 12V relay and fed into the 120V Inverter Output receptacle.

I would note for full context that the coach batteries have been upgraded to two 6V x 235 Ah, and that a Victron Battery monitor has been added. Although the RT is also equipped with a generator, my primary objective in upgrading the inverter is to be able to make coffee or otherwise use electricity if I am without shore power and camping where generator run-times are limited.

With the extra capacity, I am also thinking the new inverter could connect to the entire AC bus. But that raises two questions, neither of which are answered by the electrical distribution diagram or the RT manual.

1. Since the two outlets powered by the inverter are also powered up when shore tie or generator are connected, what segregates the other outlets to prevent their being fed while operating just on the inverter? I am thinking diodes but am not sure where they are located.

2. If the inverter is connected to the entire 120V bus, how do I (automatically) prevent inverted 120V power being sent to the Tripplite charger and back to the battery, which would result in accelerated battery drain? A relay cutout might be one way to do this.

For context, I have already upgraded my batteries to provide 235 Ah, and have installed a battery monitoring system, and am equipped with a generator. My main objective is to support coffee maker and other devices in situations such as camping without shore tie when generator run times are limited.

The Roadtrek setup for inverter is quite confusing and the wiring hard to follow sometimes, assume your RS is wired the same as our 07 Chevy with a Tripplite was.


Power comes in from the shore power cord and generator to an automatic transfer switch. Which will activate to whichever power source has power on it. If both are on, it will prioritize the shore power IIRC. It has nothing to do with inverter 110v outlets at all, under any conditions.


The power from the transfer switch goes to all the outlets except the ones that get inverter power, usually about 3 outlets in a Roadtrek are on inverter so don't get the power from the transfer switch. The power also goes to the Tripplite inverter/charger from transfer switch. All of the above power gets where it is going though the main breaker/fuse box that feeds directly from the transfer switch including the Tripplite.


The power to the Tripplite from the breaker panel will run the charger section of it and will also pass the 110v power through to the outlets that would be inverter powered. When on shore power or generator, those outlets are running on shore power, but it comes through the Tripplite inverter on the way. The inverter section does not need to be on to have all this happen.


When you are not on shore power or generator, none of the outlets in the van work for 110v unless you have the inverter on, then it power those outlets that are wired to it.



The Tripplite probably has two cords plugged into it or hardwired in. One will be the shore/generator power from the breaker panel, and the other will be the outlet from the inverter that connect it to the inverter 110v outlets. That wiring from the inverter to the those special outlets is their only connection.


It can get to be a pain to get all the outlets on inverter in the van as they all have to get to the same point to receive the power and then after that point they need to be switched with an automatic transfer switch.


I did our 190P to do all of that, but no standalone transfer switch because we don't have a generator any more.



We run all the power through the Magnum MS2000 inverter/charger. Shore to Magnum, then AC output from the Magnum from its internal automatic transfer switch to old Tripplite output wiring to the inverter outlets and also back to where the transfer switch was to pick up the rest of the wiring going to the breaker panel and all the other 110v circuits through it.
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Old 01-17-2020, 02:55 AM   #4
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Thanks Booster. I have ordered a 1500W Pure Sine Inverter (https://www.amazon.com/gp/product/B01COA0UTE/). My RT is a Sprinter so am not sure if it is exactly the same as a Chevy based RT might be.

The TrippLite does have two 110V connections as Booster describes - one feeds to a junction box that (presumably) delivers power to the inverter only outlets. The other is the 110V power supply to the battery charger. I had not considered the possibility of shore tie/generator pass through to the inverter only outlets.

So rerouting the 110V inverter outlet supply to the inverter-only outlets to come from the new (Pure Sine) Inverter may result in losing the flow through of shore tie or generator power to these outlets.

I plan to test the inverter to be sure it can actually power the keurig and TV before determining the next steps.
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Old 01-17-2020, 03:11 AM   #5
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Questions and concerns similar to your are what caused me replace my Tipplite 750 inverter/charger with another all-in-one Renogy 3000w inverter/charger. In my case it made installation a simple plug & play replacement. Just had to be sure I had room for the new unit.

I did do other upgrades at the time to lithium batteries, but that was incidental. I just had to make sure the inverter/charger I choose has a "lithium compatible" charge setting.
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Old 01-28-2020, 08:16 PM   #6
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I have started my upgrade to a Pure Sine Inverter. I selected the GoWISE Power PS1005 Pure SINE Wave Inverter 1500W Cont/3000W Peak. It is the largest rating that fits in the space I have available. I tested it today and it passed by making a cup of coffee with my Keurig off battery. It pulled a 2% drop on my battery capacity.

The 12V DC feed to the inverter will be through a 180A circuit breaker which will be mounted so it can be reached from the WC by pulling out the lower storage drawer. (Getting in from the top will require removal of bedding).

Since the electric compartment on my Roadtrek is limited, I am mounting it on the underside of the top hatch (see pictures). This allows cooling clearance all around it and the other equipment in the compartment. I had to lower the two 120V boxes (120V to and from the inverter) to improve clearance. This inverter also has a remote switch and fault indicating panel that will be mounted on the RT's main Coach control center.

I am retaining the original TrippLite 720 Inverter Charger, which will be switched to charge only mode. The Tripplite will retain its connection to the 120VAC which passes shore or generator power through to the inverter-only outlets.

To make the powering of the inverter-only outlets automatic, I am installing a American Zettler Power Relay, SPDT, 30A, 115v, Mini, 30A SPDT 120VAC AZ2280-1C-120A. The feed to the inverter-only outlets will be fed from this relay. When shore or generator power is present, it will close the circuit in the relay, directing the pass-through power from the Tripplite to the outlets. When shore or generator power is not present (normally open) the new inverter output will be directed to the inverter-only outlets. The inverter will have to be manually energized by the remote switch for these outlets to receive power (same as current TrippLite configuration).

I may or may not seek to feed the inverter to the other outlets. More on this project as I progress...
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Old 01-28-2020, 09:08 PM   #7
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Is that relay rated for maximum 840W ? Link to datasheet: https://ca-en.alliedelec.com/m/d/c08...80e312b388.pdf


I see Max. switched power: 840 W in the datasheet so would that mean loads shouldn't exceed that?
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Old 01-29-2020, 12:56 AM   #8
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engnrsrule - definitely some creative thinking and engineering on your part.

I don't mean any offense and the following is not meant as criticism. I'm not an expert in anything so they're just observations and comments and me trying to be helpful.

Some inverters can be mounted upside down and some can't. For the ones that can then through bolts would be needed I think. I can't tell if you're using bolts or screws.

This inverter: https://www.amazon.com/PWRI150012120.../dp/B07JNCD6VZ looks exactly like yours:

https://www.amazon.com/GoWISE-Power-...dp/B01COA0UTE/

On page 3 of the manual - https://www.aimscorp.net/documents/P...205%202018.pdf - Aims says "Do not mount the inverter upside down."

That's something to look into I think.
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Old 01-29-2020, 02:50 AM   #9
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You are going to have a lot of electronic equipment in this rather tight cabinet so planning for efficient venting would help to keep temperature low. At full power you could have 10% / 150W heating the compartment, for small space this is a lot.

Drilling vent holes on the bottom of the cabinet and somewhere on the top would allow hot air to leave by convection. Perhaps a pancake fan with a temperature controller could help.

I have convection and power venting in my cabinet with Magnum 1000W inverter, started with convection only and added a temperature controlled fan.
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Old 01-29-2020, 01:52 PM   #10
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Is that relay you are using for the inverter outlets a single pole only?

There are some very specific issues of neutral to ground bonding that you have to consider in any of these "add/change an inverter project" that can get very confusing and cumbersome to do properly and safely.

Bottom line is that the bonding between neutral and ground is required at any 120v power source when it is supplying the AC power.

Bottom line is also that nothing, including power sources, can be bonded when some other power source is supplying the 120v AC power.

What this means in the real world of our vans is that all the power sources need to be bonded when in use and unbonded when not in use.

Shore power is bonded at the power pole, so when ever shore power is plugged in that bond is there. An oddity here is that AFAIK the bond is there even with the pole circuit breaker off in all the poles so to get rid of that bonding in your van you have to unplug from shore power unless you have an automatic transfer switch that shuts off all three wire legs.

The generators that are built in normally are internally bonded and run through an automatic transfer switch which keeps that bond out of the circuit unless the generator is running and supplying power to the van.

Inverters can be the really dicey ones to get right as there are a lot of ways they are built and function. Typical setups that work follow, but I am sure there will be other ways also.

Use a standalone inverter that includes it's own outlet and only a DC input and no ground to the chassis. It should be internally bonded, but often isn't. If it has a GFCI it will still be quite safe, though. These are usually the smaller units and really shouldn't be used on anything that has a chassis ground as if the inverter is bonded internally that bond would be full time whenever the cord is plugged in even if the inverter is off.

Built in inverters that are intended to run van outlets that switch between shore/generator/inverter power are most likely the ones that are tougher to handle.

The easiest from many people is if it is going to be for all the outlets, you can just run the inverter output to a version that that will switch between all 3 power sources. It will automatically turn off all the but one source so all can be bonded, but will never be in the circuit together.

If you are doing just the inverter outlets like in the OP's case, it is probably easiest to get an inverter with an internal automatic transfer switch, or even more convenient an inverter/charger with that capability to minimize the AC wiring. It will switch the outlets between shore and inverter with shore power first priority and should also bond and unbond the inverter (we have seen some that don't in lower end of the market).

If you use a standalone inverter that does not have an automatic transfer switch, you would normally run the output of it to a second automatic transfer switch that switches all three wires. Take AC power from after the shore/generator transfer switch output and run it to the new transfer switch and also connect the inverter output to the transfer switch. Output from the added transfer switch would go the inverter outlets. This way the inverter can be full time bonded without any conflicts. We ran this way for several years in our Roadtrek.

A good, general, rule to have in mind is that the best way cover most scenarios is to make sure you have any switching between power sources the type of switch that switches all three 120v wires together.

All this "stuff" is why the question about the power relay to the inverter outlets.
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Old 01-29-2020, 10:20 PM   #11
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Thanks booster and markopolo for valuable feedback.

I took another look at the specs of the relays. While I believe they are technically within the rated range I do agree they are small solid state units and I want to avoid possibility of any failure. I selected a motor controller relay that should be well above my needs. JQX-40F-1Z 50A Relay SPDT High Power Motor Control 120VAC Coil -R50A120VAC.

I appreciate the catch on inverting the inverter. I have adjusted accordingly to keep it rightside up.

I appreciate the discussion of grounding. One interesting point is that the Inverter itself has a separate chassis ground connection. So in looking at how the TrippLite Inverter-Charger is connected, my installation will stay "within the box" established by the TrippLite installation.

My rig has an ABT that manages the shore tie/generator connection to the main 120V bus. When external 120V is present one breaker feeds the TrippLite, which charges the coach battery and passes 120V power through to the two "inverter-only outlets. Absent external or generator 120V there is no power to the 120V bus. Only power produced by the inverter goes to the two inverter only outlets.

I can switch the TrippLite to function as a charger only. In this mode it would also normally pass shore power through as described above. Absent the external 120V there would be no TrippLite inverted AC output.

The integration of the Pure Sine Inverter will be through the SPDT motor control relay. Relay will be operated by the 120V Shore tie/Generator feed going to the TrippLite. With no 120V present (Normally Open) the Hot will be fed from the new inverter. With external 120V present the Hot will be fed from the TrippLite pass-through.

I also appreciate the comments on cooling. The electrical compartment is small, but is only semi enclosed. The back portions are open to the void space above the rear wheel well so there is lots of air space for heat to dissipate. Also this system will seldom if ever approach high loads. The inverter will power the TV and DVD, and the coffeemaker and phone/computer chargers when boondocking. While the coffeemaker draw is high, it is brief.

.
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Old 01-29-2020, 11:02 PM   #12
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I think you have missed my point, this is not about grounding as such.



This is about neutral to ground bonding, which is totally different in need and method.



AFAIK we don't know if a Tripplite of that model autobonds or not, but that doesn't really matter anyway as you won't be using it to generate any AC power, on DC to charge the battery.



I think you may be incorrect on the generator/shore power transfer switch transferring power to the inverter outlets. I am pretty sure all that is done at the Tripplite with it's automatic transfer switch that is internal. Shore power goes to the Tripplite to be turned into DC to the battery and coach, and also passes a small amount of the AC to the inverter outlets. When shore power is removed, the Tripplite will disconnect it's AC input from the inverter outlets and will connect those inverter outlets to the inverter section of the Tripplite. The generator/shore power transfer switch only switches the power source between those two sources and feeds it to the main breaker panel where it goes to all the outlets EXCEPT the inverter outlets which get powered off of the Tripplite.


If the Tripplite is in charge only mode, I don't know what the it will do about an AC output to inverter outlets, but it will likely be passing through the AC from shore or generator. When that power goes away I don't know what would happen if you put a standalone inverter generated AC on the outlets backfeeding the Tripplite AC.



As mentioned earlier, the way that adding a bigger inverter would normally totally get rid of any AC output from the Tripplite to the inverter outlets, simply by leaving the output AC cord unplugged. You then run a standalone 3 wire switching transfer switch with AC from shore power teed in from the Tripplite input on one input and the output from the new inverter on the other input, with the output going to the inverter outlet plug that the Tripplite used to be plugged in to. You would then either bond the neutral and ground at the new inverter or make sure it already is done from the factory. It can be permanently bonded because it is disconnected as a power source when on shore power. If you only switch the hot AC line out of the inverter and permanently wire the neutral and ground to the Tripplite AC, you will have bonding at the inside the van AC through the inverter and at the power post which is not code and is not very safe.



The very last thing you want to happen in the van is to generate a hot skin, and that is what all of this is designed to help prevent, as well as assuring you won't have current flowing in the van ground wire which can cause many issues.
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Old 01-29-2020, 11:45 PM   #13
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I think this would be a sketch of what you have stock in a Tripplite equipped Roadtrek.




Would you be able to mark up or sketch what you will have with the changes? I think it would help us understand.
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Old 01-30-2020, 12:59 AM   #14
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Thanks booster.

I do get your point. I may have been misunderstood. I took your mention of a bonded ground-neutral to be the same as what I would call grounded neutral. In a house this occurs in the main box. All the neutrals in the breaker box go to a single bus that is grounded. But for the rest of the wiring in a house all of the grounds and neutrals are separate and not co-connected anywhere else. As far as I know this is not the case on an RV.

My reference to the ABT powering the inverter-only outlets was specifically through the TrippLite's pass-through function. I do understand that the ABT does not send power to those outlets directly.

Your drawing is scary - cuz it looks just like my handwriting...But there is nothing reflected in that drawing that is being modified. My new inverter is downstream of the TrippLite, along with the relay.

I do know that with the TrippLite in charge only mode, it still performs the pass through of shore/generator power.

I would say that the issue of grounded neutral is not relevant to anything I am doing since none of my mods would connect neutral to ground. If it were revealed that the RT has grounded neutral established at the box, then nothing I am doing would defeat that either.

As for the new inverter "backfeeding" into the TrippLite, I am assuming that the isolation of the two hots by means of the relay would alleviate any issues and that the connection of the TrippLite and Inverter's respective grounds and neutrals are of no consequence. (Again, the neutrals are not connected to the ground.) If your drawing is accurate, the lack of external power would seem to stop in the TrippLite.
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Old 01-30-2020, 01:35 AM   #15
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RVs are different than home, but not by much, as all the rules about bonded neutral and ground still apply.


You are relating it to a house, but you can't do that unless there is never any other power source other than shore power. With shore power the one and only bonding is at the power post just like at your service entrance at home.


When you expand that system to the more complex and common RV setups by adding other power sources a new parameter kicks in and in really complicates things. That new parameter/rule is that any new power source needs to be bonded neutral ground at that power source when it is providing AC power to the RV. This would include the generator and a hardwired inverter. On top of that new rule, is that the old requirement of one and only one bonded place is allowed. This means when each of the power source is used, it needs to bond itself and all others have to go unbonded. If you use a transfer switch that switches all three wires, the source can be permanently bonded internally because it is disconnected from the system until all three wires are connected and the transfer switch disconnects all other power sources so no other bonds in the system.


So, according to the above rules, when your new inverter is supplying AC power to the van, any part of it, it needs to have neutral and ground bonding the system and all other places need to be unbonded. You don't know if the Tripplite is bonded or not, and they may not tell you or list it in the literature. If it does autobond on it's own inverter, what is it going to do when back fed? Also if the Tripplite is backfed, is the charger going to come on and create a DC loop? All of this is why it is much better to not use any part of the Tripplite inverter/AC supply circuitry, especially with and inverter that can backfeed double the AC amps of the Tripplite inverter section and transfer switch. The other thing that can happen with a system going back through the Tripplite is what happens when shore power is accidentally plugged in while the inverter is on as you might get 3 bonded places and who knows what the Tripplite would do (hopefully fault out).


I understand that you think you haven't changed anything, but really have, plus things do need to be changed, like bonding the new inverter and making it properly connect and disconnect at the right times. If you just use the Tripplite in charge mode and disconnect the AC output, then all you need is the inverter, bonded by you if not be factory and a small transfer switch wired to the inverter, shore/generator power that can be tapped from the Tripplite input or added box, and a cord to the inverter outlet plug that the Tripplite was plugged into from the transfer switch. All bonding will be correct as shore and generator and original transfer switch aren't touched, and you will have properly bonded the new inverter and with a 3 wire switching transfer switch it will properly connect and unconnect the power and the bonding. You will also be able to have all the AC wiring be of appropriate size to handle the added power of the bigger inverter as you don't know what is inside the Tripplite that would only put out 700 watts of AC power.
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Old 01-30-2020, 01:55 AM   #16
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On edit, I gave a bit of not accurate information about the type of transfer switches used. I said 3 wire switching which for the bonding issues is not needed, only hot and neutral needed o be switched. The ground switching need was from a different discussion hazard topic. I will add diagram from Magnum for inverter/charger combinations with automatic internal transfer switch and automatic internal neutral ground bonding to show how they do it and explain it.


This is what I have been describing and covers all the the issues with two added parts.









This is the transfer switch we used with a 1500watt psw inverter to feed just the inverter circuits, plus we had wired the microwave outlet to them and taken it off the normal outlet circuit.


https://www.amazon.com/Xantrex-80809.../dp/B004S5Y158
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Old 01-30-2020, 09:23 AM   #17
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Does it all come down to whether neutral and ground are bonded in the new inverter? If so, by breaking only the hot line, you end up with neutral/ground bonds in two places when plugged into shore power.

I think inverters classified as non-permanently installed (like the Gowise unit in this topic) have neutral and ground bonded together.
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Old 01-30-2020, 12:22 PM   #18
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Does it all come down to whether neutral and ground are bonded in the new inverter? If so, by breaking only the hot line, you end up with neutral/ground bonds in two places when plugged into shore power.

I think inverters classified as non-permanently installed (like the Gowise unit in this topic) have neutral and ground bonded together.

If the unit is internally and permanently bonded will really only determine if you would need to bond it yourself or not, I think, for a wired in system like this would be. I don't think it would change anything in how it the wiring would be done. Yes, it really does just boil down to the very simple idea that you want neutral and ground bonded at one and and only one spot in a system and that bond should be at whatever power source is providing the power. That means no unbonded systems and no multiply bonded systems.


I would suspect that many/most/all of the temporary use units would or should be bonded, but I don't know if they are. I also think the lines of permanent and temporary install are getting pretty blurred with more and more of them having outlets on them, but really intended to be bolted in and used just like the hard wired units. Most manuals and spec sheets don't say if they are bonded or not, or if it is automatic. I haven't seriously dug around to see what UL, ETL, and other codes say about bonding in mobile power stuff lately. When I searched it back when I was putting in our systems there wasn't a lot on it, with Magnum instructions being the best description. Back then even Magnum had a way to easily disable the auto bond as there seemed to be some marine? applications that didn't want it. The new Magnum manual is more solid on not disconnecting it.


I think the only time you could get away with using a single hot wire relay or switch would be if you had an inverter that was a standalone with no transfer switch but did autobond. I don't know if anyone even makes one that way.


It is kind of scary when I think of how many times I have been asked how to make a double male end extension cord so people could use it to connect an inverter or generator with outlets built in to hard wired outlets in their RV or in their house even where they would be certain to have two bonds.


To complicate it all further, I would suspect that all of the stuff involved with inverters would also apply to the standalone generators, but at least those are rarely permanently connected to the RV wiring and most always will come in on the shore power line which should make them OK as long as they are bonded.
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Old 01-30-2020, 12:38 PM   #19
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......................It is kind of scary when I think of how many times I have been asked how to make a double male end extension cord so people could use it to connect an inverter or generator with outlets built in to hard wired outlets in their RV or in their house even where they would be certain to have two bonds.....................
They call that a Dead Man's plug. I used one once instead of a proper transfer switch and smoked the inverter first time out. I couldn't believe I forgot to unplug it on first use! You can't rely on memory for stuff like that - way too dangerous. In hindsight, I was really lucky that the idea was a rapid failure and that it failed as it did as it could have been worse.

Re N-G bond, here's a snippet from Xantrex:

Quote:
The 120 Vac output PROsine 1000 and PROsine 1800 inverters are designed with the output neutral bonded to (connected to) ground, as required by Canadian and U.S.electrical codes and standards. The purpose of this N-G bonding is to ensure there is no voltage on the output neutral with respect to ground. This maintains the expected normal state of a 120 Vac system—the line conductor is at 120 Vac above ground and the neutral conductor is at (or close to) zero volts above ground.
Some units shipped out in error without N-G bonding and customers were instructed to have the units repaired.

Quote:
As a result of the missing N-G bonding, the neutral voltage may rise above ground, typically by approximately 60 Vac, creating a shock hazard on circuits and loads connected to the inverter. Other than this neutral-to-ground voltage, the inverter operates normally, so this hazard could go unnoticed.
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Old 01-30-2020, 01:01 PM   #20
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They call that a Dead Man's plug. I used one once instead of a proper transfer switch and smoked the inverter first time out. I couldn't believe I forgot to unplug it on first use! You can't rely on memory for stuff like that - way too dangerous.

Re N-G bond, here's a snippet from Xantrex:

Some units shipped out in error without N-G bonding and customers were instructed to have the units repaired.

That is a good explanation of the need of bonding and more detailed than the standard "you need a bond or your ground wire is of no use" because of no return path so it would run high also.


Although in a van with no full time true earth reference there lots of scenarios, I think, that can cause issues. I think the one we here most often with the two bond thing is that the ground turns into a current carrying wire, which is a strict no-no in pretty much all codes and rules and it can happen even with earth ground through shore power.


Here is a Gopower video on their bonding setup.


https://gpelectric.com/neutral-to-gr...erter-charger/
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