220v setup/EG4 3000 inverter

[tomy2]

not sure how to wire this setup . combining two EG4 3000 inverters , so I can have 220v circuits . this amateur diagram shows how i think it should be , but is it needed to match the L1 and L2 wires? the 2nd pic shows a setup where Will put both the hots on L2 . i'm using 16 400 watt panels and 4 EG4 lifepo 5kw batterys.

 

[FilterGuy]

I do not have direct experience with the EG43K, but that looks correct.

A couple of observations:

1) AC In breaker size
The 60A breaker on the AC side seems a bit high. 6000W/120V=25A The manual talks about using 10AWG for the AC wires. For 10AWG wires, it should be a 30A breaker. If a larger breaker is used, a larger wire would be needed and I do not know if the connectors on the inverter can handle larger wires.

Note: I have always wondered what the true max current on the AC in is. If in pass-through mode, presumably, it can pass through 3000W (3000W/120V=25A). The spec sheet says it can charge 60A into the battery. (60x55V = 3300W) On the AC side, this is 3000W/120V=27.5A. If it is in passthrough and charging at the same time this would be 25A + 27.5A = 52.5A. This would need at least a 6 AWG wire and the 60A breaker as you show. I presume the inverter reduces the battery charge as the output load ramps up...... but I can not confirm that.

2) AC out breaker placement.
The drawing implies the 30A double pole breaker is external to the load box. Why not use breakers in the load box?

 

[FilterGuy]

Dang. I hit 'post' before I discussed the last items: Grounding and Ground-Neutral bonding.

Grounding
1) There should be a ground wire from the 220V sub-panel to each of the inverter AC In terminals and another ground wire from the 220V sub panel to the distribution panel.

N-G Bonding.
1) Since it is labeled '220V Sub-panel, I presume there is no bond between Neutral and ground in the sub-panel but there is an N-G bond in a main panel someplace upstream from the sub-panel.
2) There should not be an N-G bond in the distribution panel.
3) What gets into the unknown is what happens with N-G bonding internal to the inverter. I believe the inverters have an internal n-g bonding screw, but EG4 said they stopped shipping the inverters with the screw last November.
- If there are no screws, then there is no NG bond when the inverters are powered from the battery. - This is not good.
- If the screws are in place on both inverters, then there are TWO NG bonds when powering from the battery. - This is not good

EG4 has said they are coming out with a solution, but I have not heard what it is yet. In the meantime, I would recommend that ONE of the two inverters gets the bonding screw.... but this requires opening up the inverters. I would advise talking to your distributor before doing that.

 

[Rednecktek]

Umm... is picture 2 of the panel upside down or am I really THAT drunk right now? ?

 

[tomy2]

Umm... is picture 2 of the panel upside down or am I really THAT drunk right now? ?

sorry, I tried to fix it , but failed

 

[Rednecktek]

 

[Mithril]

I do not have direct experience with the EG43K, but that looks correct.

A couple of observations:

1) AC In breaker size
The 60A breaker on the AC side seems a bit high. 6000W/120V=25A The manual talks about using 10AWG for the AC wires. For 10AWG wires, it should be a 30A breaker. If a larger breaker is used, a larger wire would be needed and I do not know if the connectors on the inverter can handle larger wires.

Note: I have always wondered what the true max current on the AC in is. If in pass-through mode, presumably, it can pass through 3000W (3000W/120V=25A). The spec sheet says it can charge 60A into the battery. (60x55V = 3300W) On the AC side, this is 3000W/120V=27.5A. If it is in passthrough and charging at the same time this would be 25A + 27.5A = 52.5A. This would need at least a 6 AWG wire and the 60A breaker as you show. I presume the inverter reduces the battery charge as the output load ramps up...... but I can not confirm that.

2) AC out breaker placement.
The drawing implies the 30A double pole breaker is external to the load box. Why not use breakers in the load box?

So fun fact, the online manual, paper manual, and SS customer service have managed to give me FOUR different answers on AC breaker size.

For my own use case I went with a 30A breaker, and I've just set my charging current fairly low. In the case of needing to charge via a generator bypass input I can adjust it.

The inverter does NOT adjust the charging automatically sadly.

Note I am using a single Unit and have not tested charging behavior with more than a single unit.

My unit did NOT come with the internal grounding screw (as in other recently shipped EG4 units) but DOES disconnect N in and N out.
Per advice on this forum I have tied N in and N out to maintain the N-G bond from the main panel even when inverting, and have verified for MY unit it does not cause a double bond. I have NOT seen a software update for the smaller inverters that the bigger ones have (to change the internal bonding relay behavior.

You can test if you have the screw by checking continuity (with the inverter OFF and disconnected) between case ground (and AC in ground) and N out, and between N in and N out.
- If you have the ground screw and the same firmware I do, you will see continuity between N out and ground only.
- If the relay is engaged (not sure if it is latching) you'll see continuity between the N in and N out but NOT with ground.
- If you see NO continuity then you 99% do not have a ground screw.
- If you get continuity between all 3, it's defective somehow.

 

[tomy2]

Dang. I hit 'post' before I discussed the last items: Grounding and Ground-Neutral bonding.

Grounding
1) There should be a ground wire from the 220V sub-panel to each of the inverter AC In terminals and another ground wire from the 220V sub panel to the distribution panel.

N-G Bonding.
1) Since it is labeled '220V Sub-panel, I presume there is no bond between Neutral and ground in the sub-panel but there is an N-G bond in a main panel someplace upstream from the sub-panel.
2) There should not be an N-G bond in the distribution panel.
3) What gets into the unknown is what happens with N-G bonding internal to the inverter. I believe the inverters have an internal n-g bonding screw, but EG4 said they stopped shipping the inverters with the screw last November.
- If there are no screws, then there is no NG bond when the inverters are powered from the battery. - This is not good.
- If the screws are in place on both inverters, then there are TWO NG bonds when powering from the battery. - This is not good

EG4 has said they are coming out with a solution, but I have not heard what it is yet. In the meantime, I would recommend that ONE of the two inverters gets the bonding screw.... but this requires opening up the inverters. I would advise talking to your distributor before doing that.

I have the ground as you describe, their is a ground nut on the outside of each unit, maybe it provides the NG bond, when in battery mode. I have been running these inverters separately for months without problems. I used the 30amp box to save space in the load center and so it is more accessible . I used the 60amp breaker because it is called for and those wires are #8. the cables to the battery busbar are #6 as specified . I'm hoping that I don't have balancing problems, their is no way I will add a $900 transformer

 

[tomy2]

So fun fact, the online manual, paper manual, and SS customer service have managed to give me FOUR different answers on AC breaker size.

For my own use case I went with a 30A breaker, and I've just set my charging current fairly low. In the case of needing to charge via a generator bypass input I can adjust it.

The inverter does NOT adjust the charging automatically sadly.

Note I am using a single Unit and have not tested charging behavior with more than a single unit.

My unit did NOT come with the internal grounding screw (as in other recently shipped EG4 units) but DOES disconnect N in and N out.
Per advice on this forum I have tied N in and N out to maintain the N-G bond from the main panel even when inverting, and have verified for MY unit it does not cause a double bond. I have NOT seen a software update for the smaller inverters that the bigger ones have (to change the internal bonding relay behavior.

You can test if you have the screw by checking continuity (with the inverter OFF and disconnected) between case ground (and AC in ground) and N out, and between N in and N out.
- If you have the ground screw and the same firmware I do, you will see continuity between N out and ground only.
- If the relay is engaged (not sure if it is latching) you'll see continuity between the N in and N out but NOT with ground.
- If you see NO continuity then you 99% do not have a ground screw.
- If you get continuity between all 3, it's defective somehow.

there is a firmware update for the 3000.https://eg4electronics.com/wp-content/uploads/2022/10/NEW-V2-3K.zip

 

[tomy2]

I do not have direct experience with the EG43K, but that looks correct.

A couple of observations:

1) AC In breaker size
The 60A breaker on the AC side seems a bit high. 6000W/120V=25A The manual talks about using 10AWG for the AC wires. For 10AWG wires, it should be a 30A breaker. If a larger breaker is used, a larger wire would be needed and I do not know if the connectors on the inverter can handle larger wires.

Note: I have always wondered what the true max current on the AC in is. If in pass-through mode, presumably, it can pass through 3000W (3000W/120V=25A). The spec sheet says it can charge 60A into the battery. (60x55V = 3300W) On the AC side, this is 3000W/120V=27.5A. If it is in passthrough and charging at the same time this would be 25A + 27.5A = 52.5A. This would need at least a 6 AWG wire and the 60A breaker as you show. I presume the inverter reduces the battery charge as the output load ramps up...... but I can not confirm that.

2) AC out breaker placement.
The drawing implies the 30A double pole breaker is external to the load box. Why not use breakers in the load box?

After more thought , it should not matter which side of the panel box the neutral wire goes to , since they are bonded? which is good since I cut the wire too short to cross the panel

 

[FilterGuy]

The inverter does NOT adjust the charging automatically sadly.

That is an important bit of data. Have you measured more than 30A on the input?

their is a ground nut on the outside of each unit, maybe it provides the NG bond, when in battery mode.

No, the ground nut is not part of the dynamic bonding.

My unit did NOT come with the internal grounding screw (as in other recently shipped EG4 units) but DOES disconnect N in and N out.
Per advice on this forum I have tied N in and N out to maintain the N-G bond from the main panel even when inverting, and have verified for MY unit it does not cause a double bond. I have NOT seen a software update for the smaller inverters that the bigger ones have (to change the internal bonding relay behavior.

That should work. EG4 has never endorsed this, but many people have successfully done it.

After more thought , it should not matter which side of the panel box the neutral wire goes to , since they are bonded? which is good since I cut the wire too short to cross the panel

Hmm... this comment made me go back and look at the diagrams......and something seems off about the neutral wiring.

In the 240V sub-panel, all neutrals should be tied together, but the diagrams above show them as separate.... Can you confirm the sub-panel has all of the neutrals tied together? Also, can you confirm that since it is a sub-panel, the grounds are kept separate from the Neutrals?

In the distribution panel, the neutrals should be tied together but the diagrams show them as separate. Can you confirm the distribution panel has all of the neutrals tied together? Also, can you confirm that the grounds are kept separate from the Neutrals in the distribution panel?

 

[Rednecktek]

In the 240V sub-panel, all neutrals should be tied together, but the diagrams above show them as separate.... Can you confirm the sub-panel has all of the neutrals tied together? Also, can you confirm that since it is a sub-panel, the grounds are kept separate from the Neutrals?

According to the picture this panel is set up as the main panel and all the Neutral and Ground wires are going to the same bus bar. If it's just a "Sub Panel" being USED as a Main Panel then it is wired correctly.

 

[FilterGuy]

According to the picture this panel is set up as the main panel and all the Neutral and Ground wires are going to the same bus bar. If it's just a "Sub Panel" being USED as a Main Panel then it is wired correctly.

Hmmmm
The OP said

the 2nd pic shows a setup where Will put both the hots on L2

I assumed this means it is not a picture of the OPs set-up.... but I could be wrong.

Looking at the first picture, I wonder if the OP is confused about what breakers are on Line 1 vs Line 2.




It kinda looks like he assumes all the Line 1 breakers are on the right and all the line 2 breakers are on the left. That is not correct. The breakers going down each side alternate between Line1 and Line 2 .
The breakers that go to the inverter should be right next to each other on one side of the box and should have a pin tying them together so if one pops, both pop.

 

[FilterGuy]

 

[Rednecktek]

He's bring in the hot legs through a double pole breaker, that's correct.

 

[Mithril]

I have the ground as you describe, their is a ground nut on the outside of each unit, maybe it provides the NG bond, when in battery mode. I have been running these inverters separately for months without problems. I used the 30amp box to save space in the load center and so it is more accessible . I used the 60amp breaker because it is called for and those wires are #8. the cables to the battery busbar are #6 as specified . I'm hoping that I don't have balancing problems, their is no way I will add a $900 transformer

The ground on the case SHOULD be 100% tied to ground on AC in internally, regardless of ground BONDing screw, or the position of the relay.

I believe this is placed to ground the inverter when AC in is not used so that the case is grounded.

 

[Mithril]

there is a firmware update for the 3000.https://eg4electronics.com/wp-content/uploads/2022/10/NEW-V2-3K.zip

Thats from late late year, and I don't *think* it has the update that the big brothers of this unit do.

 

[Mithril]

That is an important bit of data. Have you measured more than 30A on the input?

I have not tried loading output + charger that much. However I have verified that as far as I can tell the charger is "dumb", there is no place to add an input limit for the total system (you can change the max charge AMPs). Manual testing showed that when the charger is on, total AC input = charger AC demand + AC output, with the charger AC demand remaining steady within a margin of error. I would NOT assume or rely on dynamic charging input.

No, the ground nut is not part of the dynamic bonding.

Per my continuity measurements, I agree. It is internally bonded to the AC in ground. I would imagine that one OR the other should be used but not both.

That should work. EG4 has never endorsed this, but many people have successfully done it.

I'm not sure I personally trust what SS endorses at the moment, seems to be a high deal of confusion with their own products...

 

[FilterGuy]

I have not tried loading output + charger that much. However I have verified that as far as I can tell the charger is "dumb", there is no place to add an input limit for the total system (you can change the max charge AMPs). Manual testing showed that when the charger is on, total AC input = charger AC demand + AC output, with the charger AC demand remaining steady within a margin of error. I would NOT assume or rely on dynamic charging input.

If you ever get a chance to load it with ~3K while the charger is working, it would be interesting to see if the input goes above 30A.

 

[tomy2]

That is an important bit of data. Have you measured more than 30A on the input?

No, the ground nut is not part of the dynamic bonding.

That should work. EG4 has never endorsed this, but many people have successfully done it.

Hmm... this comment made me go back and look at the diagrams......and something seems off about the neutral wiring.

In the 240V sub-panel, all neutrals should be tied together, but the diagrams above show them as separate.... Can you confirm the sub-panel has all of the neutrals tied together? Also, can you confirm that since it is a sub-panel, the grounds are kept separate from the Neutrals?

In the distribution panel, the neutrals should be tied together but the diagrams show them as separate. Can you confirm the distribution panel has all of the neutrals tied together? Also, can you confirm that the grounds are kept separate from the Neutrals in the distribution panel?

yes, my diagram is misleading, the neutral bars are tied together in both of the boxes. and there is a separate ground bar. and I do sometimes forget that L1 and L2 are accessible from both the left and right. so are you saying that the outside ground screws shouldn't be connected from one inverter to the other? and only one should be connected to the groundbar? filter guy are you as stoked as me, to see our endless winter ending, mid eightys this weekend ! thanks for sharing your knowledge, my electric ability is maxed out.

 

[FilterGuy]

so are you saying that the outside ground screws shouldn't be connected from one inverter to the other?

Yes. I rarely ever use the ground screws.

and only one should be connected to the groundbar?

Both inverters should have a wire from the 240V sub panel ground bar to the AC input ground.

filter guy are you as stoked as me, to see our endless winter ending, mid eightys this weekend !

Yes, but I cheated. I just got back from 3 weeks in Florida and the Virgin Islands. I escaped all the March storms

 

[tomy2]

Yes. I rarely ever use the ground screws.


Both inverters should have a wire from the 240V sub panel ground bar to the AC input ground.


Yes, but I cheated. I just got back from 3 weeks in Florida and the Virgin Islands. I escaped all the March storms

Good timing ,

 

[CNC Guy]

Note, your post states “Will put both hots on L2”. That is not correct. Both AC output breakers are on the same side, but the bus bars on a breaker panel stager the connection from the left to right as you go down the panel. So two breakers next to each other are actually connected to L1 and L2. Not sure if someone mentioned this already. Hope it helps.