EcoFlow Delta Pro / Transfer switch/ AC Charging

[justanothercoder]

I just purchased a Delta Pro. My (hopeful) use case is to use it as a UPS/down grid backup, with AC charging It is connected to a Reliant ProTran 2 Transfer Switch via the 30A RV connector with an adapter. I have used the transfer switch many times with a gas powered generator.

When I plugged the Delta Pro in I ran into a couple of issues that I'm hoping someone can help with:
1) Charging with a GFCI outlet immediately tripped GFCI.
2) After adding a 2 prong/3 prong adapter to the AC charging cable, it did charge.. however:
3) When I attempted to power the transfer switch while charging from AC (in grid position, have not tried gen position), the GFCI tripped again.

Based on some reading, I have ordered one of these(

Neutral-Ground Bonding Plug​

): https://www.amazon.com/dp/B07F4R7BDL?psc=1&ref=ppx_yo2ov_dt_b_product_details

But I am wondering if i am doing it right.

Any help is appreciated
Thanks!
--Brendan

 

[JAS]

I think you may be running into the same problem I was having with my MPP Solar AIO feeding my EmerGen Transfer Switch...

Since most generator transfer switches don't switch neutral, they share the neutral in your main panel (where the N/G bond is). When you feed your EcoFlow AC in coming from a receptacle (that I assume is attached to your main panel circuit), you are giving the transfer switch an input that already has a N/G bond. When the GFCI sees the "downstream" N/G bond (kind of a loop through your transfer switch back to the main panel, it trips.

My conclusion was one of the following options:

1. Feed the AC in with a line not using a GFCI. (I don't feel comfortable with this option)
2. Don't ever charge while inverting. (I don't like this option either. Defeats the purpose of buying an Inverter/Charger.)
3. Swap the transfer switch out for one that does switch neutral (https://www.nooutage.com/xrk.htm)
   1. This does require that you can make the EcoFlow bond N/G while inverting too (I can on my MPP unit with some additional wiring), maybe the N/G bonding plug would do the trick while Inverting, but would cause a problem when you are plugged in charging, as you would again have (2) N/G bonds
   2. If you can't change the N/G bond behavior on the EcoFlow, than you'll have to look at options 1 or 2, with option 2 being the preferred option of the two... (IMO)

 

[justanothercoder]

I think you may be running into the same problem I was having with my MPP Solar AIO feeding my EmerGen Transfer Switch...

Since most generator transfer switches don't switch neutral, they share the neutral in your main panel (where the N/G bond is). When you feed your EcoFlow AC in coming from a receptacle (that I assume is attached to your main panel circuit), you are giving the transfer switch an input that already has a N/G bond. When the GFCI sees the "downstream" N/G bond (kind of a loop through your transfer switch back to the main panel, it trips.

My conclusion was one of the following options:

1. Feed the AC in with a line not using a GFCI. (I don't feel comfortable with this option)
2. Don't ever charge while inverting. (I don't like this option either. Defeats the purpose of buying an Inverter/Charger.)
3. Swap the transfer switch out for one that does switch neutral (https://www.nooutage.com/xrk.htm)
   1. This does require that you can make the EcoFlow bond N/G while inverting too (I can on my MPP unit with some additional wiring), maybe the N/G bonding plug would do the trick while Inverting, but would cause a problem when you are plugged in charging, as you would again have (2) N/G bonds
   2. If you can't change the N/G bond behavior on the EcoFlow, than you'll have to look at options 1 or 2, with option 2 being the preferred option of the two... (IMO)

Thanks - you have confirmed my concerns, and I agree that wiring around GFCI (especially when a real ground loop could actually occur) is a REALLY bad idea.

2 more things (thanks for your time @JAS):
1) I would also like to charge the ecoflow with a gas generator in extended grid down situations. Since they are both floating neutral (generator is portable, with standard frame grounding). Any issues with this?
2) As ridiculous/inefficient as it might sound: Is it correct to assume that charging via the DC XT60 input port using a AC->DC power supply should have no issues, as the GFCI will be handled at the power supply that I would drive the charging with? I'm looking at just standing up a few dedicated solar panels for the Ecoflow, but would like to understand all my options
Thanks again!
--Brendan

 

[JAS]

1) I would also like to charge the ecoflow with a gas generator in extended grid down situations. Since they are both floating neutral (generator is portable, with standard frame grounding). Any issues with this?

That should work fine.

2) As ridiculous/inefficient as it might sound: Is it correct to assume that charging via the DC XT60 input port using a AC->DC power supply should have no issues, as the GFCI will be handled at the power supply that I would drive the charging with?

Probably OK too. However, with some of the MPP/Growatt units, they can invert directly from solar and there was discussion about whether they bonded N/G when inverting directly from solar..

 

[justanothercoder]

Thanks @JAS !

 

[EJansen]

Just randomly stumbled upon this thread, since I also have a Delta Pro and like to see what people are doing with them, however, I also think that what you're mentioning is the issue that I have with my wildy over complicated solar shed. Here's the thread with the diagrams, and the last one discusses the issue:

Solar Shed with Transfer Switch

Hi Guys, I haven't been getting much traction in the other posts revolving around my question, so I figured I'd start a new thread here - since maybe it's not a beginner question that belongs in beginners corner. I short, I want to cut my teeth on a smaller project but at some point I want to...

diysolarforum.com

I'm going to go look at the 'innerds' of the transfer switch tomorrow - I thought it switched both the hot and neutral, but if it only switches the hot, then that lines up with what I was seeing and what I discussed in my post.

Eric

 

[JAS]

Just randomly stumbled upon this thread, since I also have a Delta Pro and like to see what people are doing with them, however, I also think that what you're mentioning is the issue that I have with my wildy over complicated solar shed. Here's the thread with the diagrams, and the last one discusses the issue:

Solar Shed with Transfer Switch

Hi Guys, I haven't been getting much traction in the other posts revolving around my question, so I figured I'd start a new thread here - since maybe it's not a beginner question that belongs in beginners corner. I short, I want to cut my teeth on a smaller project but at some point I want to...

diysolarforum.com

I'm going to go look at the 'innerds' of the transfer switch tomorrow - I thought it switched both the hot and neutral, but if it only switches the hot, then that lines up with what I was seeing and what I discussed in my post.

Eric

I also thought the GoPower TS switched neutral too. I had a clone of that switch at our cabin for a while and thought I remember it switching neutral ?‍

Is that Renogy in your drawing an inverter only or an inverter/charger?

 

[EJansen]

Yeah, I took a look, and it appears that it does switch the neutral, so now im back to not being sure why it doesn't work. The Renogy is just an inverter.

 

[JAS]

Does the shed panel and/or the "Distribution Protection Box" have N/G bonded in it?

 

[EJansen]

Does the shed panel and/or the "Distribution Protection Box" have N/G bonded in it?

Here's a snip from the drawing regarding bonding - I turned the drawing into half drawing, half documentation.

Panel Bonding:

If the inverter is dead and house is powering the coil on the Secondary AC Contactor, the Normally Closed (NC) switch (# 2), will open, breaking the bond between the Neutral and the ground, since it would no longer be isolated from the house, and there is already a Neutral to Ground bond in the main panel.

Conversely, if the inverter re-gains power and the Primary AC Contactor disconnects the house, the house can no longer power the coil on the Secondary AC Contactor, so # 2 will close, connecting the Neutral to the Ground, bonding the connections together, which is the default, since it’s a Normally Closed (NC) switch.

I could message you a high-resolution image if you cared to take a look - definitely not using any sort of electrical engineering standards / symbols. I'm just a computer nerd that likes to solve puzzles and it's kinda like coding a bit.

 

[JAS]

Well... it's making me dizzy to think that hard about your setup ;-)

But... all I know is that a GFCI will definitely trip when it sees a downstream N/G Bond. If you have some kind of automated switching going on, it is possible that it just doesn't switch fast enough before the GFCI freaks out ?‍ If that's the case...

Maybe it would be better to remove any N/G bonding downstream and just use a N/G Bonding plug on the Renogy (if it has receptacles) or if it's hardwired just bond N/G there?

 

[EJansen]

Well... it's making me dizzy to think that hard about your setup ;-)

But... all I know is that a GFCI will definitely trip when it sees a downstream N/G Bond. If you have some kind of automated switching going on, it is possible that it just doesn't switch fast enough before the GFCI freaks out ?‍ If that's the case...

Maybe it would be better to remove any N/G bonding downstream and just use a N/G Bonding plug on the Renogy (if it has receptacles) or if it's hardwired just bond N/G there?

Yeah, the contactors are slow, so that's what I was thinking the issue was at first. The last notes that I have on what I did when I last looked into it (last August) was:

"In troubleshooting, if I remove the neutral wire from the second contactor (Blue Normally Closed contactor as depicted in the image, that bonds the ground and neutral, if Power Comes from the inverter), it'll switch back and forth between house power and Solar/Inverter Power. Am I missing something obvious or is it possible that I need to somehow integrate a delay in that contactor?"



What I didn't add in that post is that, if I recall correctly, is that I'd remove the neutral wire from the transfer switch side connected via Wago connector (circled on both ends of the wire in blue), make sure everything was switched over to the house, and all was good, but then touch the Neutral back to the wago and it would still blow the GFCI.

I probably just need to quadruple check everything, but I'm pretty certain that the last 3 times I checked, the physical implementation matched the drawing. Oh well, no biggie, after the 200AH Lossigy battery upgrade, with the 600 watts of panel, I've yet to need to plug back into the house. Now I just want to know, for closure.

 

[JAS]

I think I'd just eliminate all the moving parts (everything in the Distribution Protection Box besides the Transfer Switch) and just run the Renogy into a small 2-pole breaker box prior to the transfer switch (for no other reason than to bond N/G).

 

[ijain314]

I just purchased a Delta Pro. My (hopeful) use case is to use it as a UPS/down grid backup, with AC charging It is connected to a Reliant ProTran 2 Transfer Switch via the 30A RV connector with an adapter. I have used the transfer switch many times with a gas powered generator.

When I plugged the Delta Pro in I ran into a couple of issues that I'm hoping someone can help with:
1) Charging with a GFCI outlet immediately tripped GFCI.
2) After adding a 2 prong/3 prong adapter to the AC charging cable, it did charge.. however:
3) When I attempted to power the transfer switch while charging from AC (in grid position, have not tried gen position), the GFCI tripped again.

Based on some reading, I have ordered one of these(

Neutral-Ground Bonding Plug​

): https://www.amazon.com/dp/B07F4R7BDL?psc=1&ref=ppx_yo2ov_dt_b_product_details

But I am wondering if i am doing it right.

Any help is appreciated
Thanks!
--Brendan

Hey I am also in the same boat I think. What I am trying to do is power the transfer switch while my crital load is in Gen mode but then also charge the delta pro from an outlet connected to the main panel. The idea is that I can put a smart outlet between the delta pro and the AC input to that I can change the battery when the cost of power is cheap but when its hight I can continue to run off battery. Would this work? I would be keep the critical load in Gen mode so that it would pull power from the delta pro. Just not sure I can have it delta pro charging on at the same time from the main panel. The transfer switch shared a ground and neutral with the main panel. Any thoughts on this would be great.

 

[ijain314]

I also posted this question on ecoflows FB page. It was suggested to use an AC to DC inverter and plug it into the back of the delta pro. This would solve the issue.

 

[EJansen]

Probably not what you're looking for, and it's also not exactly cheap, but what I did to deal with the issue was to buy the EcoFlow Smart Home Panel, since it's an all-in-one type system that charges the Delta Pros as well as integrates automation for time of use, has app control from your phone, and other cool features. Figured it was at least worth honorable mention, incase you weren't aware of it.

 

[hamm55]

On further research I ran across this on the web. I could not find it on the Reliance web site so not sure if discontinued or what. Anyway one could provide their own kit as the components are available anywhere (HD, Lowes, etc). You will also need to provide like kind C/AFCI and/or GFCI breakers in the transfer switch to tie in/control neutrals from the switch to the breakers/wiring on the load panel.

One of my other concerns is being code compliant with the GFCI/AFCI residential code. I have an electrician scheduled to come out this week to give me a quote on installing my Pro/Tran2 6cr switch and will know for sure if this will comply with the code or not. I can live with the breaker trip nuisance for now either way.

NK06 Pro/Tran2 Neutral Kit

 

[hamm55]

On further research I ran across this on the web. I could not find it on the Reliance web site so not sure if discontinued or what. Anyway one could provide their own kit as the components are available anywhere (HD, Lowes, etc). You will also need to provide like kind C/AFCI and/or GFCI breakers in the transfer switch to tie in/control neutrals from the switch to the breakers/wiring on the load panel.

One of my other concerns is being code compliant with the GFCI/AFCI residential code. I have an electrician scheduled to come out this week to give me a quote on installing my Pro/Tran2 6cr switch and will know for sure if this will comply with the code or not. I can live with the breaker trip nuisance for now either way.

View attachment 104148

NK06 Pro/Tran2 Neutral Kit

Update: Decided to install the Reliance Pro/Tran2 6cr switch without the neutral kit. Found out that the c/afci -gfci breaker nuisance trip will still occur as the neutral kit only provides c/afci -gfci circuit protection (does not switch the neutral) while in generator mode if you replaced the standard breakers in the transfer switch with c/afci -gfci ones. Also still trying to confirm if the neutral kit is required by code or not if the circuit is protected by c/afci -gfci.


See link for setup/install: https://diysolarforum.com/threads/ecoflow-delta-pro-and-transfer-switch-setup.45061/

 

[aunsafe2015]

Probably not what you're looking for, and it's also not exactly cheap, but what I did to deal with the issue was to buy the EcoFlow Smart Home Panel, since it's an all-in-one type system that charges the Delta Pros as well as integrates automation for time of use, has app control from your phone, and other cool features. Figured it was at least worth honorable mention, incase you weren't aware of it.

I'd been thinking about buying a Delta Pro and Smart Home Panel but decided against it b/c its not really compatible with a large (11-12 kW) professionally installed solar array that I'd like to have installed in a year or two.

Did lack of compatibility with large solar arrays dissuade you at all?

I suppose I could still have both the solar array and the Delta Pro + Smart Home Panel; the solar array just would not charge the Delta Pro batteries during outages.

 

[justanothercoder]

Just circling back because this thread was just updated. After learning about the grounding issues, I realized that working around GFCI ( a safety feature) with a bonding plug was something that I was not comfortable with. As crazy as it may sound, I ended up building a 1200w off grid array for dedicated charging for the Delta Pro. While it did cost a bit more, so far I'm quite happy with this, and it led me in the direction of a small amount of load shedding, and a setup that is probably a bit more resilient in grid down situations (given that there is sun available, which is reasonable here in Northern California). I still have a gas genset for backup, but will only use that to charge the Delta Pro when/if needed.