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EG4 18k PV back-feeding on GEN port

No progress after a month ?
I'm considering an 18kpv but am now concerned about the GEN port.
Aahhh, the annoying dilemma...
I'm traveling, so this will be the short version...
Ideally, I'd like the process to be fully automated (Enphase set the bar quite high at the onset), but haven't gotten to that point - yet.
Each time I contact Signature Solar (seller) I receive the same boilerplate reply. Last time it looked promising as a trouble ticket was assigned and "someone" was supposed to call back. Nothing ever happened. Either they're too busy, understaffed, or don't care.

What I observed - under ~20% SOC, the 18K behaves differently than > 20%. By differently, I mean it completely ignores the threshold settings I depend on. (Side note: I had SOC fall from ~47% to 0% in a matter of minutes, once, see above - WTF? not sure still - that's about a 28.8 kWh drop of all the batts, on the BMS most likely) Unfortunately, I'm looking for more stable behavior. The 18K is now like a chick who promises to call you, but you never know if/when she will do so. Enphase have never given me such grief since Nov. 2021 turn-up.

What I wanted to do originally, was to have the 18k pull from GEN, SOC allowing of course, and I can control the physical GEN hot connection using the Enphase IQ Load Controller when Enphase SOC reaches a certain range (sunny day, generating power) to prevent Enphase batts from draining to 0%. I can spice up the situation by having the 18K request GEN start and couple that with the IQ Load Controller. That will work, provided the 18K GEN ports close, which they now fail to do. This is not very complicated. I have 15.36 kVA at 240v, (peak 23.04 kVA) + 12.54 kVA at 240v when sunny to work with, so basically a very quiet generator as far as the 18K is concerned. This does work, or I should say did work for several days (see early descr.) I'm simply not convinced the 18K behavior is stable enough to do this.

Where I am at now: SOC allowing, Enphase closes a relay (via IQ Load Controller) and "sheds" load when passing a certain SOC threshold (sunny day) via a 240v AC to 48v DC 35A charger. I know, I know, Panel DC -> AC -> DC -> AC -> house, but it works, predictably, each sunny day (I have plenty more panels in storage and a shit ton of roof space remaining to install them). A minor nuisance is that the AC to DC charger goes quiet (0A) at random. That's a totally different, non-related behavior - yet another issue to deal with - easy to solve though, as it resets next day.

I'm experimenting with Telco power equipment at the moment (the Chargeverter runs on two such packs, in parallel) and if successful, I will simply use the existing charger as a "48v float" but rely solely on telco power packs, in 25A step increments (they are stupidly stable), as many as needed to potentially charge 120 kWh within a single day, similar to
.

In the future, I will purchase another 18k EG4 (or possibly a 18k LuxPower) + a batch of 60 kWh (and a few accessories while at it), but this time from current connected and work with them on the original issue as I feel they would be far more helpful/capable and interested in solving the unstable behavior. I don't particularly dislike the 18k, just wish it was more predictable in its behavior as presently I'm convinced that major bugs have yet to be worked out.
 
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Aahhh, the annoying dilemma...
I'm traveling, so this will be the short version...
Ideally, I'd like the process to be fully automated (Enphase set the bar quite high at the onset), but haven't gotten to that point - yet.
Each time I contact Signature Solar (seller) I receive the same boilerplate reply. Last time it looked promising as a trouble ticket was assigned and "someone" was supposed to call back. Nothing ever happened. Either they're too busy, understaffed, or don't care.

What I observed - under ~20% SOC, the 18K behaves differently than > 20%. By differently, I mean it completely ignores the threshold settings I depend on. (Side note: I had SOC fall from ~47% to 0% in a matter of minutes, once, see above - WTF? not sure still - that's about a 28.8 kWh drop of all the batts, on the BMS most likely) Unfortunately, I'm looking for more stable behavior. The 18K is now like a chick who promises to call you, but you never know if/when she will do so. Enphase have never given me such grief since Nov. 2021 turn-up.

What I wanted to do originally, was to have the 18k pull from GEN, SOC allowing of course, and I can control the physical GEN hot connection using the Enphase IQ Load Controller when Enphase SOC reaches a certain range (sunny day, generating power) to prevent Enphase batts from draining to 0%. I can spice up the situation by having the 18K request GEN start and couple that with the IQ Load Controller. That will work, provided the 18K GEN ports close, which they now fail to do. This is not very complicated. I have 15.36 kVA at 240v, (peak 23.04 kVA) + 12.54 kVA at 240v when sunny to work with, so basically a very quiet generator as far as the 18K is concerned. This does work, or I should say did work for several days (see early descr.) I'm simply not convinced the 18K behavior is stable enough to do this.

Where I am at now: SOC allowing, Enphase closes a relay (via IQ Load Controller) and "sheds" load when passing a certain SOC threshold (sunny day) via a 240v AC to 48v DC 35A charger. I know, I know, Panel DC -> AC -> DC -> AC -> house, but it works, predictably, each sunny day (I have plenty more panels in storage and a shit ton of roof space remaining to install them). A minor nuisance is that the AC to DC charger goes quiet (0A) at random. That's a totally different, non-related behavior - yet another issue to deal with - easy to solve though, as it resets next day.

I'm experimenting with Telco power equipment at the moment (the Chargeverter runs on two such packs, in parallel) and if successful, I will simply use the existing charger as a "48v float" but rely solely on telco power packs, in 25A step increments (they are stupidly stable), as many as needed to potentially charge 120 kWh within a single day, similar to
.

In the future, I will purchase another 18k EG4 (or possibly a 18k LuxPower) + a batch of 60 kWh (and a few accessories while at it), but this time from current connected and work with them on the original issue as I feel they would be far more helpful/capable and interested in solving the unstable behavior. I don't particularly dislike the 18k, just wish it was more predictable in its behavior as presently I'm convinced that major bugs have yet to be worked out.
Hi! I’m so sorry you’ve had trouble with support! If you’d like to reach out to me with your name and email address, I’d like to get your case escalated and taken care of!
 
Just confirming:
Off-grid
Gen port: enphase
Grid port: generator
Correct?
off-grid - YES 100%
Enphase system controller (load side) - OUT
18K GEN port - IN (I have seen this put amperage out, opposite of what was expected. Blew me away, but no damage since the "generator" is a bank of 4x10Ts that deliver amps & take then all day long) Feq. synch is ok since the 18K GEN port is supposed to do that anyways before closing contacts. Last tests it has never closed contacts.
Ps see diagram for all details (3MASTER with LOAD)
 
Just curious: what is controlling the enphase?

Being on the Load side, the 18k pv can't turn the enphase off when the generator is running. The generator prevents the 18k pv from frequency shifting to throttle enphase production. In that configuration, unless something else is controlling the enphase, you risk backfeeding the generator. AC pv on the load side is not recommended because thev18k pv cannot disconnect the pv to prevent over production.

I suggest putting the generator on the grid port, and the enphase on the gen port.

Note: Page 43. Diagram 4.9 has the AC PV into the gen port, not the panel on the load output. Page 25, section 4.7 discusses allowing ac pv on gen port, and generator on grid port when off grid.
 
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No progress after a month ?
I'm considering an 18kpv but am now concerned about the GEN port.
What's your concern? Are you planning to put a load on the gen port while it's tied to the grid port?
 
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