Wireing up the GS Inverter to your Main.

[The Blind Wolf]

As the topic implies.

 

Since I can not see Sean wire frensy rig to his two mains.

 

I want to make sure I understand correctly, that I basicly run the l1 l2 and N to the main to a 240 breaker, with the n going to the N bar.  I'm guessing I need a 60a 240v breaker, or do I need one rated a bit higher if they make one like a 35a 25a 70a?

 

Since I'll be living by my self, I won't have to worry about somebody going to the main and flipping the grin main on.

 

Since I'm running two GS I'll need two breakers one for each.  Today since I'm in North AL, it was like 1f degrees and I checked my power usage, well it peaked at 12700 watts.  Thats running the main heat pump heat strip unit, and two 1200 watt infered heaters, and my normal stuff. 

 

Once I get the GS inverters, I'm going to disable the heater on the  central unit, and get another small room heater, save power and won't pull so much.

 

I also do got a grounding rod outside that I use to ground all my chargers, and I'm guessing it be fine to wire it to the two gs inverters as well.  Or will it matter since the N would be basically the same thing going to the main?

 

Sid, was wondering, is there any chance for these inverters to sense if the main power came on to shut off their power?  I know you said it can do Grid power once you get the codeing done, but didn't know if it might have a safety in case somebody did switch on the main breaker.  I wish they made a big enough transfer switch, I can't find one that is over 60a 240.  I got one that is rated at 50a, but that would not use the full gs load.

[Sid Genetry Solar]

So this gets complicated, particularly for your desired setup.  You want 2 inverters in "daisy chain" mode (tests are going well btw, just need to put a bunch of safeties on it!)  For setup:

• Inverter A: configured for Normal Mode.  This is the "master" inverter.
• Inverter B: configured for SLAVE-Parallel.  This is the "slave" inverter.

The "master" inverter gets all 3 output legs (L1, N, L2) directly connected to the breaker panel.  Note that if the grid mains is already "on" when this inverter is turned on, it will throw an "Output Error" and refuse to start up.  However, flipping the grid breaker "on" while the is inverter running will most likely result in catastrophic failure of the inverter.  Detecting this is extremely difficult; it's best not to get in this situation in the first place.

The "slave" inverter gets both input (NOT THE OUTPUT) legs also directly connected to the breaker panel across L1-L2 (240v).  Separate 25-30A breakers on each inverter would be highly recommended.  The output terminals of the slave inverter are NOT connected.  (It actually backfeeds power out of the "Input" terminals in Parallel/Grid Tie mode.)  This allows it to disconnect the input power if necessary, as well as properly sync to the input signal.

You might consider connecting the input AC mains to a separate breaker panel, and wiring it to the input of the MASTER inverter.  This would allow safe access to grid power if your batteries just don't have enough juice to last through the night.  Automatic transfer and/or automatic battery charging can be done (though this may cause issues resulting from the SLAVE inverter...I'll have to think about it.)

[The Blind Wolf]

Okay, you lost me on the Slave setup.

 

The Master, gets output to the breaker as normal, then the slave input goes to the breaker as well?  what do the output of the slave go to then?

 

I only need to 60a breakers right?  Also I will be useing a Champion 30a RV gen invert for battery charging.  So I guess I would hook that ot the mast input?

[Sid Genetry Solar]

I would recommend two 25-30A breakers, one per inverter.  6kw @ 240v is 25A.

Yes, slave input goes to the breaker panel; I would recommend it being on a separate breaker from the master inverter.  Output of the slave unit is not connected.  The total power of the inverters is only ever "seen" at the breaker panel.

Yes, connect the generator to the master inverter input.  Wiring up generator start may be a bit of a challenge for you...for whatever unknown reason, I used a 3-pin micro-XLR jack for the gen start control outputs.  Rev. B GS inverters use a much more standard 5.08mm 3-pin push-release wire connector.  (Wouldn't it be nice to ask Amazon Alexa, "Alexa, can you start the generator?"  haha, so many possibilities here!)

[The Blind Wolf]

Well the Champion RV gen I got has remote start :P.  all I have to do is click a button on the key fog and it'll start up.  hmmmm. I thought that 3k was 30 amps, so 3.6k is 30 amp then. so I need a double or I guess they call them two pole 50a breaker.  Still lost on the slave, I'm guessing you useing the slave input side as a grid tie basicly from what I'm understanding.  So the third GS if I decide to get one for some odd reason would be setup the same way, so the input to the breaker would change Hz from 60 to 61 and the third would be 63Hz phasing.

 

well I forgot what protocal it is, but, Itff or something like that is uced on scripting for amazon and google from what I heard.

[Sid Genetry Solar]

Protocol, you're referring to IFTTT (If This Then That)?? 

Calculating amps is pretty easy via Ohm's Law.  Divide watts by volts to get amps.  And divide watts by amps to get volts.  So 3000W / 240v = 12.5A.  This is assuming split-phase operation is desired; GS inverters are capable of running 120v mode, which will double the amperage available: 3000W / 120v = 25A.  If in this case, you could run the 2 inverters one per phase, one in Normal Mode, and the other in SLAVE-SPLIT (running 180 degrees out of phase from the "master").  This limits charge to 120v, though.

Yes, slave "input" is used as the grid-tie output, as it can be switched on and off by the CPU, as well as it having AC wave polarity detection (required for sync!)

They all run at the AC output frequency set by the Master inverter; frequency shift is used in grid-tie systems to "throttle" down the slave units as necessary (60-62Hz).

[The Blind Wolf]

Yes, IFTTT  is what I ment, smart things and google and amazon uses that.  I think its the most strip down you can get on devices.

 

Anyhow.  Well, you saying 120v charging, well, that just it, my RV gen has a 30a 120 pure sign output.  and pretty much my whole main box is almost filled up it has 6 slots left for three 240v, if I can use only one 240 breaker for both GS inverters, that might work better, and  be able to use the charging.  I don't know if they make a 100A breaker or not. and I'm not sure what wire size would I need to go for, I know 10/3 is for 30a service.  I'm guessing it would be a 8/3 for 50a service,  since each wire would be able to handle 50a so two wires would be the 100a service.

 

[Waterman]

On 2/16/2021 at 6:13 PM, The Blind Wolf said:

As the topic implies.

 

Since I can not see Sean wire frensy rig to his two mains.

 

I want to make sure I understand correctly, that I basicly run the l1 l2 and N to the main to a 240 breaker, with the n going to the N bar.  I'm guessing I need a 60a 240v breaker, or do I need one rated a bit higher if they make one like a 35a 25a 70a?

 

Since I'll be living by my self, I won't have to worry about somebody going to the main and flipping the grin main on.

 

Since I'm running two GS I'll need two breakers one for each.  Today since I'm in North AL, it was like 1f degrees and I checked my power usage, well it peaked at 12700 watts.  Thats running the main heat pump heat strip unit, and two 1200 watt infered heaters, and my normal stuff. 

 

Once I get the GS inverters, I'm going to disable the heater on the  central unit, and get another small room heater, save power and won't pull so much.

 

I also do got a grounding rod outside that I use to ground all my chargers, and I'm guessing it be fine to wire it to the two gs inverters as well.  Or will it matter since the N would be basically the same thing going to the main?

 

Sid, was wondering, is there any chance for these inverters to sense if the main power came on to shut off their power?  I know you said it can do Grid power once you get the codeing done, but didn't know if it might have a safety in case somebody did switch on the main breaker.  I wish they made a big enough transfer switch, I can't find one that is over 60a 240.  I got one that is rated at 50a, but that would not use the full gs load.

Are you looking for a manual or automatic transfer switch?  And do you plan to switch it while under load or only with the loads turned off?   MSC has a 100 Amp Generac manual transfer switch but takes a month from order to delivery. A Transfer Switch is rated at load switching capacity so it actually may be able to handle a higher load if the loads are applied after the switch is made. Depends on the unit.

Our small transfer is a 50 Amp that runs a panel that in theory could draw 80 Amps if all the breakers hit their peaks at the same time. It was approved on the electrical drawings supplied to the County on a stamped electrical engineers approval. Our other Transfer Switch is huge. It is rated for 600 Amps but has been fuse limited to 200 Amps. If the center lug kit was installed, it could do 3 phase power. It can be switched under full load as the fuses are the Slow Blow type. I would have preferred a smaller unit but when you only have one day to get the item and it is 100 miles away and your employer is the one who locates it for you, you take what you can get.  And like in Texas right now, there might not be any others available. It has been in use since 1992 with no problems. The input sides are fused at 200 Amps but the Emergency side then has a 50 Amp breaker for the Generators. The Generators themselves have their own breakers and connect by 4 wire plugs and cables.

You can get a 63Amp rated 4 pole automatic Transfer Switch made by the Chinese. As to whether it can handle that full load or not, I can't say. I use mine for only a 15 Amp load and even that isn't what is switched. The switching is actually done by a 40 Amp rated relay. I did things that way as then the contacts in the transfer switch only see the control circuits loads and not the power loads. And it is far simpler to replace the relay than the powered switch. The ground circuit is also switched by the powered switch. That was done so that the two Grounds are isolated from each other so an inverter that is 110 Volts has the Neutral connection isolated from the house Neutral and Ground.  Some of the inverters do not have a true Neutral as on 110 only, the second leg is also hot. The unit also has a time delay relay in it so that while a transfer of inverter to powered outlets is delayed, the transfer to commercial power is instant. Reason for that is so that an inverter can power up without load and then accept the loads after a 30 second delay. The transfer itself is instant once the delayed timer relay times out. Inverter shutdown results in instant transfer to commercial power if available. As you can see, I tend to over build things.

[Sid Genetry Solar]

4 hours ago, The Blind Wolf said:

Anyhow.  Well, you saying 120v charging, well, that just it, my RV gen has a 30a 120 pure sign output.

So your generator is a single-phase 120v unit?  That's very important to know and communicate to Sean for setup--the inverter can be configured for either 120v or 240v input, but not both.  It has to be configured at setup before shipping (yes, it's possible to change later down the road, but doing requires voiding your warranty).

[The Blind Wolf]

Yes, if I can still keep it master and slave 240v with 120v charging, I would go that route, just incase one inverter goes down for some reason.

 

Waterman

 

Thansk for the info,  I think I won't need a transfer, since it would mean I have to contact the main power company to come out, pull the meter and or take me off the pole, then install a service disconnect on the outside which comes from the meter, then from that to a transfer, then back to main.

 

Right now the way they got houses here built, the power comes directly from the meter to the main, the main breaker is the only cut off for power, which I don't like.    I do have a 50A 240v transfer switch laying around, but, not sure if that is 50a per leg or both legs combine.  If it was per leg, I could use to gs setup like side said each one 120v in different phase and use it then.  But, like I said it would mean rewireing the main and meter to be able to pull from the grid it self.

[Sid Genetry Solar]

This starts getting complicated.  The charge voltage also determines the "parallel" voltage.  If it's set for 120v charge, then it will be 120v "parallel", not 240v.  This may take a bit of thought to figure out.

I do not expect the GS inverters to be failure prone.  (Obviously, once we get them out in the field, we might discover some things to tweak.)

It sounds like you need the "master" inverter to have 120v "input", for your generator.  The "slave" inverter has to have 240v "input" for parallel mode.  This unfortunately means that they aren't swappable; however, in the event that the "master" inverter should go kaput for whatever reason, you could disconnect it from the system, and switch the "slave" inverter to "normal" system mode, and rewire the panel to the AC output leads...

[The Blind Wolf]

Hmmmm. okay, so if its going to be that big of a issue, I guess both needs to be set as 120 then.  Either way both GS will be tied into the same battery bank.  I'll just have to go get a 8/4 wire and a 100 amp 240v breaker if they make one.

[Waterman]

3 hours ago, The Blind Wolf said:

Yes, if I can still keep it master and slave 240v with 120v charging, I would go that route, just incase one inverter goes down for some reason.

 

Waterman

 

Thansk for the info,  I think I won't need a transfer, since it would mean I have to contact the main power company to come out, pull the meter and or take me off the pole, then install a service disconnect on the outside which comes from the meter, then from that to a transfer, then back to main.

 

Right now the way they got houses here built, the power comes directly from the meter to the main, the main breaker is the only cut off for power, which I don't like.    I do have a 50A 240v transfer switch laying around, but, not sure if that is 50a per leg or both legs combine.  If it was per leg, I could use to gs setup like side said each one 120v in different phase and use it then.  But, like I said it would mean rewireing the main and meter to be able to pull from the grid it self.

There are some kits out there that will allow you to do the work just in the main panel. That only requires either skill or turning off the main breaker. What they do is lock out the Main Breaker and allow an extra breaker to be turned on. Many old installation in industry worked that way as it was cheap and so was the labor to have someone operate them.  We had them in use up into the 2000s. Our pump station was a bit more modern as we had a small automatic transfer switch and also keyed Main and large generator breakers. To close the large generator breaker you had to turn off and lock the main, remove the key and move it to the generator breaker, unlock it, turn it to on, then engage one of the generator breakers. We could sync the two main generators and switch between them while running either automatically or manually.

If there is enough room alongside your main panel, you could install a sub panel fed by a transfer switch. That is what we had originally and can still use. That would be a remove some wires and move to new panel and replace the old breakers that fed them with a new one for the transfer switch. I installed the large transfer switch when we had no commercial power so I didn't have to worry. We had no clue as to when we would get power back. Which was 5 weeks later. There weren't even any power lines on the pole in front of the house although the transformer was still there and went for about another 5 years after Andrew before it went bad.

If it is labeled as a 50 A 240 V Transfer Switch then that is 50 Amps per side. Most will still use a common Neutral in the wiring. Not good with 120V inverters as the N is still hot on them But okay on 240V units or if yours breaks the Neutral also.

[Sid Genetry Solar]

So in that case, you'd have the "master" 6kw GS inverter running in 240v split-phase output, with 120v charge input (for the generator).

And the "slave" 6kw GS inverter running 120v "parallel" mode...but this will only "boost" one phase of your breaker panel, not both split phases.  Even if the inverter is configured for 240v output--since the output is not used for parallel--this will limit you to 3kw "parallel" max.  If the inverter is configured across the board for single-phase 120v, then you can get 6kw @ 120v output...but once again, it is only going to be a single-phase unit.

This might be getting a bit overcomplicated.  Inverter input/output voltage configuration cannot be changed without voiding your warranty.

[The Blind Wolf]

Uhm, I bought two gs to get 12k, so either I can't use charging to get my 12k or if I use my chargeing and only get 6k and not split.  Geesh, I do got a 120v to 240v stepup transformer.  I think its the 5k model, could I just run the gen to it then take the two 120 outputs and pull from each L1 and l2, cause I checked and its split on the output and run that to the input of the gs?  Would that solve the problem?

[Sid Genetry Solar]

31 minutes ago, The Blind Wolf said:

Uhm, I bought two gs to get 12k, so either I can't use charging to get my 12k or if I use my chargeing and only get 6k and not split.  Geesh, I do got a 120v to 240v stepup transformer.  I think its the 5k model, could I just run the gen to it then take the two 120 outputs and pull from each L1 and l2, cause I checked and its split on the output and run that to the input of the gs?  Would that solve the problem?

Oh you can get 12kw total...just the "master" has to have a 120v input for the generator (max 3kw input, as it's 120v), and a 240v split-phase output.  "Slave" has to be set for 240v input; this will get you the full 6kw output across 240v. 

If you need more than 3kw from the generator, you'd need to bump the generator output up to 240v to get the full 6kw charge of the "master" inverter.

Hopefully your house is fairly balanced across the phases, as the "master" inverter would be doing a fair bit of "autoformer" action to produce the Neutral (as the "parallel" unit doesn't provide the Neutral line).

[The Blind Wolf]

Okay, lets break this down.  I still hook up both the two gs to the main each on its own 50a 240v breaker.  a Black wire, and yellow wire I think is the l2 color, then the white wire and go to the neutral bar, I do this for both circuits in my main.

 

Both GS are setup as master and slave.

 

and far as I know my breaker is balance, since all 240v is basically on one side of the breaker and all the 120v breakers are on the other side.

 

Now what do you mean about the neutral wire?  That would be the job of both inverters wouldn't it?  I mean its the power source, so you got to have a neutral comeing from it.  The Generator would be I think a floating neutral , not sure I know its a inverter generator, so basically like a third inverter, since its putting out pure sign wave.

 

your throwing me off on the 3k and 6 k lol parts.

 

If your meaning that it would only charge at 3k level, that is fine with me.

 

Almost sounding like I'm going to have to find a high amp 24v charger and just run the generator to charge the bank instead of use the gs to do it.

 

wonder where I can get a cheap 24v high output charger for cheap, I don't want to use my flycow it can push 10 amp, but, that would take forever to charge a bank.

[Sid Genetry Solar]

I'm just trying to figure out exactly what you're trying to do, and provide a suggestion for how the inverters need to be configured to best meet your needs.  Bit of confusion resulting from it, I think.

1. Yes, you connect both GS inverters to the breaker panel, each on a separate 240v breaker.  You'll be fine with a 30A breaker on each (unless you already have 50A breakers), as 6kw / 240v = 25A.
2. First inverter is set up as the master inverter, the System Mode is left at the default "Normal."
   • 240vAC split-phase output
   • 120vAC single-phase input, for the generator.
     • Due to the 25A transformer current limit, the 120v single-phase input will limit at 120v * 25A = 3,000W.
   • This inverter also can control generator start if so desired (automatic gen start based on battery voltage)
     • 3kw @ 24v is 125A; I have yet to run charge tests on the GS inverter, but it's possible we might be able to charge @ 80A without overheating.  There are much greater losses in charge mode than inverter mode, due to the system using the backsplash diodes on the FETs for rectification (which drop 0.6-1.0v)...this likely will thermally limit the maximum charge current.  But way over 10A, that's for sure!
3. Second inverter is set up as the slave/paralleled inverter.  System Mode is set to "SLAVE: Parallel".
   • 240vAC split-phase output, not connected
   • 240vAC single-phase input, connected to the breaker panel for parallel backfeed.  Only 2 wires go to the panel from this inverter, NOT the neutral wire.  Why?  I don't have a big enough relay to disconnect 2 legs of the transformer at the same time...and if Neutral is connected, the inverter is not able to completely disconnect the input power source.  Might be possible with parallel mode, but definitely not grid-tie.
     • If Neutral is not connected, the transformer in the Master inverter will still produce Neutral from the collective power.

 

Hope this clears things up for both of us?

[The Blind Wolf]

Yep, so I still get 12k output to the main, but limited on chargeing since basicly I'm only useing 1 hot wire,, but at 125a charging thats is perfit anyhhow since the gen is a 30a max anyhow, even at 25a that won't over load the generator.

 

yes, I keep forget to do the math on conversion, for some reason in my head I thinking l1 is 25a l2 is 25a so the breaker for a 240v would be a 50a since a 240v breaker is nothing more then two 120 that are made into one throw switch.  Unless your saying the breaker rating is 25A but is two 25A lol that might be where my confusion is.   😛

 

because to me 12k is 100A if you converter 12k by 120v  w/V=100a

[The Blind Wolf]

So Master, gets Yellow, Black and Nutral wires ran to the main

 

Slave gets yellow and black run to main from input side of gs

 

The gen gets hooked up to master on input side l1 and Nutral wire, 

 

Master/slave/gen gets grounded.

[Sid Genetry Solar]

Sounds about right.

[InPhase]

Next we should talk about that grounding setup. Sticking rods into the ground can do more harm than good. There's two kinds of grounding at work here: Equipment grounding, and equipotential earth grounding. They are different things that perform different functions but are tied together at the service entrance. It's unfortunate that they are both called "ground". There's sooooo much confusion around it.