EG4 6500EX Inverters and Double Throw (On-Off-On) Switch

[Henderson]

Hi, so I'm working on my build which includes 2x EG4 6500EX inverters in split phase. I would like to utilize a double throw switch (on-off-on). This switch would allow me to direct power to my house from the solar or placing the switch in another position, it will allow me to power directly from the grid ignoring the solar system altogether. I have been looking at the various 100amp double throw switches and there's a double pole and a tripple pole. The double pole switches only the hots, i.e L1 and L2 are switched, whereas the tripple or 3-pole switches L1, L2 and N. Below are the 2 switches I'm considering. My question is this...if I use the double pole, it means that the neutrals from the AC output from the grid, AC input into the inverter and AC output from the inverter would all have to be tied together and bonded. Is this a safe configuration, especially when the EG4s go into bypass mode? Another option, which is much cheaper is to use one of the automatic transfer switches and set it to manual mode only...is this also a safe option to use? With the 3-pole switch, L1, L2 and N are switched so I don't have to tie all the neutrals together like how I would have to with the 2-pole...at least I think that's how it works.

2 Pole Link:

https://www.amazon.com/Siemens-DTGNF223R-100-Amp-240-volt-Non-Fused/dp/B00TEADCKM/ref=sr_1_4?crid=2A4JIHVNK0EZD&keywords=2+pole+double+throw+100+amp+switch&qid=1675722934&sprefix=2+pole+doubl%2Caps%2C136&sr=8-4

3 Pole Link:

https://www.amazon.com/Siemens-DTNF323R-240-volt-Non-Fused-Switches/dp/B00PP4T5JI/ref=sr_1_14?crid=3642FBJ7AXR8V&keywords=3+pole+double+throw+100+amp+switch&qid=1675723045&sprefix=3+pole+double+throw+100+amp+switch%2Caps%2C147&sr=8-14

ATS Switch Link:
https://www.amazon.com/Automatic-Tr...9Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

Thanks in advance.

 

[SolarScott]

Hi, so I'm working on my build which includes 2x EG4 6500EX inverters in split phase. I would like to utilize a double throw switch (on-off-on). This switch would allow me to direct power to my house from the solar or placing the switch in another position, it will allow me to power directly from the grid ignoring the solar system altogether. I have been looking at the various 100amp double throw switches and there's a double pole and a tripple pole. The double pole switches only the hots, i.e L1 and L2 are switched, whereas the tripple or 3-pole switches L1, L2 and N. Below are the 2 switches I'm considering. My question is this...if I use the double pole, it means that the neutrals from the AC output from the grid, AC input into the inverter and AC output from the inverter would all have to be tied together and bonded. Is this a safe configuration, especially when the EG4s go into bypass mode? Another option, which is much cheaper is to use one of the automatic transfer switches and set it to manual mode only...is this also a safe option to use? With the 3-pole switch, L1, L2 and N are switched so I don't have to tie all the neutrals together like how I would have to with the 2-pole...at least I think that's how it works.

2 Pole Link:

https://www.amazon.com/Siemens-DTGNF223R-100-Amp-240-volt-Non-Fused/dp/B00TEADCKM/ref=sr_1_4?crid=2A4JIHVNK0EZD&keywords=2+pole+double+throw+100+amp+switch&qid=1675722934&sprefix=2+pole+doubl%2Caps%2C136&sr=8-4

3 Pole Link:

https://www.amazon.com/Siemens-DTNF323R-240-volt-Non-Fused-Switches/dp/B00PP4T5JI/ref=sr_1_14?crid=3642FBJ7AXR8V&keywords=3+pole+double+throw+100+amp+switch&qid=1675723045&sprefix=3+pole+double+throw+100+amp+switch%2Caps%2C147&sr=8-14

ATS Switch Link:
https://www.amazon.com/Automatic-Transfer-Electrical-Selector-Switches/dp/B07RQVDJ71/ref=sr_1_1_sspa?crid=2D6DDL5ZAEETT&keywords=automatic+transfer+switch+100+amp+240v&qid=1675723157&sprefix=100+amp+automa,aps,142&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEzQUM0QUJUTzlLRUNRJmVuY3J5cHRlZElkPUEwMzg0Mjg2M1NaQVBBNUc1SEVESSZlbmNyeXB0ZWRBZElkPUEwMzU4NDY1M0hOM04zVzJESU03NCZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

Thanks in advance.

IF you go with a two pole switch, I purchased two Eaton 100 amp from Ebay that I paid $250 each. I would be glad to get rid of them just to recoup a little of my money. If that is the way you decided to go.

 

[Adam De Lay]

With the 2 pole switch, you would have a Common Neutral. There’s actually several threads in the forum where people discuss this, one of which is this one:

Newer models of EG4 6500ex are built without the bonding screw

EG4 did release a new video yesterday. It was about their new "chargeverter" though.

diysolarforum.com

We’re kinda waiting to see if SS will officially support this type of installation now that they’re not including the bonding screws in the inverters.

A 3 pole switch would completely isolate your system from the grid.

 

[EastTexCowboy]

Hi, so I'm working on my build which includes 2x EG4 6500EX inverters in split phase. I would like to utilize a double throw switch (on-off-on). This switch would allow me to direct power to my house from the solar or placing the switch in another position, it will allow me to power directly from the grid ignoring the solar system altogether. I have been looking at the various 100amp double throw switches and there's a double pole and a tripple pole. The double pole switches only the hots, i.e L1 and L2 are switched, whereas the tripple or 3-pole switches L1, L2 and N. Below are the 2 switches I'm considering. My question is this...if I use the double pole, it means that the neutrals from the AC output from the grid, AC input into the inverter and AC output from the inverter would all have to be tied together and bonded. Is this a safe configuration, especially when the EG4s go into bypass mode? Another option, which is much cheaper is to use one of the automatic transfer switches and set it to manual mode only...is this also a safe option to use? With the 3-pole switch, L1, L2 and N are switched so I don't have to tie all the neutrals together like how I would have to with the 2-pole...at least I think that's how it works.

2 Pole Link:

https://www.amazon.com/Siemens-DTGNF223R-100-Amp-240-volt-Non-Fused/dp/B00TEADCKM/ref=sr_1_4?crid=2A4JIHVNK0EZD&keywords=2+pole+double+throw+100+amp+switch&qid=1675722934&sprefix=2+pole+doubl%2Caps%2C136&sr=8-4

3 Pole Link:

https://www.amazon.com/Siemens-DTNF323R-240-volt-Non-Fused-Switches/dp/B00PP4T5JI/ref=sr_1_14?crid=3642FBJ7AXR8V&keywords=3+pole+double+throw+100+amp+switch&qid=1675723045&sprefix=3+pole+double+throw+100+amp+switch%2Caps%2C147&sr=8-14

ATS Switch Link:
https://www.amazon.com/Automatic-Transfer-Electrical-Selector-Switches/dp/B07RQVDJ71/ref=sr_1_1_sspa?crid=2D6DDL5ZAEETT&keywords=automatic+transfer+switch+100+amp+240v&qid=1675723157&sprefix=100+amp+automa,aps,142&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEzQUM0QUJUTzlLRUNRJmVuY3J5cHRlZElkPUEwMzg0Mjg2M1NaQVBBNUc1SEVESSZlbmNyeXB0ZWRBZElkPUEwMzU4NDY1M0hOM04zVzJESU03NCZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

Thanks in advance.

I did exactly what you're talking about except I have two MPP LV6548s. I went with a Seimens 100 amp three pole double throw, which looks like the same one from your link. It was about $840 in November when I bought it and they're $940 now from Home Depot, but for me it's worth it. As @w8dev pointed out, it allows you to completely isolate from the grid. I've followed the threads on this and on the discussion about common neutral. Maybe that would be fine but there is a lot of back and forth from very knowledgeable people. I figure if I totally isolate then I don't have to worry whether it's going to cause a problem or not.

Here's a link to the Seimens from HD. Way cheaper than from Amazon.

Siemens General Duty Double Throw 100 Amp 240-Volt 3-Pole Outdoor Non-Fusible Safety Switch DTGNF323R - The Home Depot

Double Throw switches are intended to transfer loads from 1 power source to another. All 2 and 3-pole double throw switches are suitable for use as service equipment including non-fusible versions when

www.homedepot.com

 

[Henderson]

With the 2 pole switch, you would have a Common Neutral. There’s actually several threads in the forum where people discuss this, one of which is this one:

Newer models of EG4 6500ex are built without the bonding screw

EG4 did release a new video yesterday. It was about their new "chargeverter" though.

diysolarforum.com

We’re kinda waiting to see if SS will officially support this type of installation now that they’re not including the bonding screws in the inverters.

A 3 pole switch would completely isolate your system from the grid.

Thanks for the feedback

 

[Henderson]

I did exactly what you're talking about except I have two MPP LV6548s. I went with a Seimens 100 amp three pole double throw, which looks like the same one from your link. It was about $840 in November when I bought it and they're $940 now from Home Depot, but for me it's worth it. As @w8dev pointed out, it allows you to completely isolate from the grid. I've followed the threads on this and on the discussion about common neutral. Maybe that would be fine but there is a lot of back and forth from very knowledgeable people. I figure if I totally isolate then I don't have to worry whether it's going to cause a problem or not.

Here's a link to the Seimens from HD. Way cheaper than from Amazon.

Siemens General Duty Double Throw 100 Amp 240-Volt 3-Pole Outdoor Non-Fusible Safety Switch DTGNF323R - The Home Depot

Double Throw switches are intended to transfer loads from 1 power source to another. All 2 and 3-pole double throw switches are suitable for use as service equipment including non-fusible versions when

www.homedepot.com

Thanks...I'm in agreement with you in terms of the complete isolation. There's no substitute for peace of mind.

 

[Gavin Stone]

I used a Siemens isolation switch also. I think it may be a bit overkill in this case. But it really is all about peace of mind.

 

[Henderson]

Here's the change over switch I decided to go with. The 2 inputs are completed isolated. It's a 3 phase switch (4 poles) but I will use only 3 poles for L1, L2 and N. This is rated at 125A so it'll be perfect for my 100A service at the house. From the spec sheet, it can take up to 1 AWG wire.

I'm expecting to get it in hand a few weeks from now. Got it for around U$250 plus shipping.

 

[Adam De Lay]

Here's the change over switch I decided to go with. The 2 inputs are completed isolated. It's a 3 phase switch (4 poles) but I will use only 3 poles for L1, L2 and N. This is rated at 125A so it'll be perfect for my 100A service at the house. From the spec sheet, it can take up to 1 AWG wire.

I'm expecting to get it in hand a few weeks from now. Got it for around U$250 plus shipping.

View attachment 136402

View attachment 136403

View attachment 136404
View attachment 136405

Let us know what you think when you get it all installed!

 

[Patrick1]

Here's the change over switch I decided to go with. The 2 inputs are completed isolated. It's a 3 phase switch (4 poles) but I will use only 3 poles for L1, L2 and N. This is rated at 125A so it'll be perfect for my 100A service at the house. From the spec sheet, it can take up to 1 AWG wire.

I'm expecting to get it in hand a few weeks from now. Got it for around U$250 plus shipping.

View attachment 136402

View attachment 136403

View attachment 136404
View attachment 136405

Any news? Did you get/install it?

 

[Henderson]

Any news? Did you get/install it?

Hi, haven't received it as yet. The store I purchased it from on ebay does ship directly to my country so I had to send it to a shipping forwarder first. I expect to have it in hand over the next week or so. I won't have it set up until another 3 months though. I have a few minor changes to make at the house so that I can fit all the panels properly.

 

[Henderson]

Any news? Did you get/install it?

Ok. So I just got the delivery of this change over switch this morning. Was expecting it later this week but was pleasantly surprised and that's where the pleasantries ended. Item arrived damaged. Just sent a note to the store but they are in the UK so that's a major timezone difference from where I am so we'll see what they come back with. The electrical connections were somehow broken off. Not sure if this can be repaired. Will let you know what the seller says. This really sucks but hope the seller makes this right. Bought this item on eBay from Thompson Electrical Wholesale. The metal enclosure seems well built and the electrical connectors seem thick enough that they can handle the 125A current.

 

[Adam De Lay]

Ok. So I just got the delivery of this change over switch this morning. Was expecting it later this week but was pleasantly surprised and that's where the pleasantries ended. Item arrived damaged. Just sent a note to the store but they are in the UK so that's a major timezone difference from where I am so we'll see what they come back with. The electrical connections were somehow broken off. Not sure if this can be repaired. Will let you know what the seller says. This really sucks but hope the seller makes this right. Bought this item on eBay from Thompson Electrical Wholesale. The metal enclosure seems well built and the electrical connectors seem thick enough that they can handle the 125A current.

Is it broken, or are the pins at the bottom of the picture supposed to slide into terminals behind the switch? I see a bunch of screw terminals.

 

[Henderson]

Is it broken, or are the pins at the bottom of the picture supposed to slide into terminals behind the switch? I see a bunch of screw terminals.

You are absolutely correct. I see what the seller did. The seller didn't tighten the screws which caused to bus bar looking component to slide out and there was another clip that was out which is why I thought it was broken. So I slid the pins back in and tightened the screws and attached the clips and it's working now. I did a series of continuity tests on the pins of the output and both sets of inputs and everything checks out. Thanks for that suggestion. Perhaps I should've taken a closer look at it.

 

[Adam De Lay]

You are absolutely correct. I see what the seller did. The shipper didn't tighten the screws which caused to bus bar looking component to slide out and there was another clip that was out which is why I thought it was broken. So I slid the pins back in and tightened the screws and attached the clips and it's working now. I did a series of continuity tests on the pins of the output and both sets of inputs and everything checks out. Thanks for that suggestion. Perhaps I should've taken a closer look at it.

No worries. Glad it looks like it might work for you!

Unfortunately now we have to wait a few months for your tests...hehe

 

[Henderson]

No worries. Glad it looks like it might work for you!

Unfortunately now we have to wait a few months for your tests...hehe

Lol...true. Been working on this project for a while and really looking forward to getting it up and running.