Meter socket adapters?

Isn’t that what I just said? Using a standard transferswitch would not be seamless.
Ok, your posts were unclear to me. But also you have said more than once 'it can be done' meaning (I think?) that a standard ATS can be used with a multimode inverter. Which, well, depending on the inverter that's either not true or not necessary for most applications.
 
When the grid goes down, the Enphase inverters are already in synch with it, so the transition can be seamless, but what about when the grid comes back up with a random phase relationship with the inverters?
I'm not sure exactly how it works, but it's seamless, meaning I don't see the lights flicker. It's conceivable that the system sends messages to the grid forming inverters to be ready to transition, and that once prepared they can do so within a cycle or two of 'seeing' the grid voltage.

Actually a 'hard' transition to off-grid, where there's no warning of utility loss, does cause lights to flicker. Whereas a soft transition, where the MID opens on a user command, is seamless. So I think the inverters can switch modes faster when they are 'expecting' to.
 
No, you are not going to have a seamless transfer. There will be a delay stopping the inverter output, then switching the transferswitch, then switching to island mode. It can be done, just above the average electricians head, and not all that practical.
An MID provides a seamless transfer if the inverter is producing power and the grid goes down or comes back up. You are treating the inverter like a backup generator that has to be started and stopped, that design does not apply here. An MID is not a transfer switch, it's a grid isolation switch. It may include a transfer switch to send inverter power to a backup panel but that is a load shedding function and not necessary to the MID.
 
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I'm not sure exactly how it works, but it's seamless, meaning I don't see the lights flicker. It's conceivable that the system sends messages to the grid forming inverters to be ready to transition, and that once prepared they can do so within a cycle or two of 'seeing' the grid voltage.

Actually a 'hard' transition to off-grid, where there's no warning of utility loss, does cause lights to flicker. Whereas a soft transition, where the MID opens on a user command, is seamless. So I think the inverters can switch modes faster when they are 'expecting' to.
A loss of grid can cause flicker in less expensive islanding microgrids. It's all in the dollars, if you want seamless you can get it.
 
An MID is not a transfer switch, it's a grid isolation switch.
Nothing technical would prevent a generic ATS from being used as a Microgrid Interconnect Device (MID), other than its ability to talk to the main sync inverter responsible for managing the micro grid. Enphase appears to be using a RS-485 modbus type signal. Simply nothing would be landed on the generator side of the ATS.
The inverter manufacturer would need to support that of course, they could in the same way they support different manufacturers batteries using open RS-485 modbus type commands.
They could sell a device that converted the RS-485 modbus type signal to a ATS type signal. (This could be hacked together using a PLC)
I could see that as a upgrade path for a building that has a old generator and ATS and no longer wants or needs a generator but has a PV system.
Probably not a seamless transfer either.
 
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Retyping the acronyms helps me remember what they are, its a new one for a old concept from synchronous co-generation.
A co-gen plant would use a industrial ATS along with point of common coupling (PCC) and a Real-Time Automation Controller (RTAC) such as SEL 700G
https://selinc.com/products/700G/
And for an example none of that SEL gear needs to be in one manufacturers 'eco system', and it may be installed on the NEC side of things, just more industrial than residential.
 
Nothing technical would prevent a generic ATS from being used as a Microgrid Interconnect Device (MID),

Well, they follow different product standards, and the ATS would have to get listed to UL1741 to perform that function, which typically includes waiting 5 mins before reconnecting to the grid and other things that AFAIK a generic ATS does not do.

other than its ability to talk to the main sync inverter responsible for managing the micro grid. Enphase appears to be using a RS-485 modbus type signal.

They're using CAM, not RS 485.

...
They could sell a device that converted the RS-485 modbus type signal to a ATS type signal. (This could be hacked together using a PLC)
I could see that as a upgrade path for a building that has a old generator and ATS and no longer wants or needs a generator but has a PV system.
Probably not a seamless transfer either.

I appreciate what you're getting at with respect to having an open standard for MIDs the way there is an open standard with ATSs (actually a couple). A generic ATS is not well suited to serving as an MID in a new install, but if an existing ATS were also listed to be able to serve as an MID that could save labor if a client wanted to replace or augment a generator with a multimode inverter. Conversely, with the right standards in place, I could see an MID being repurposed to work with a generator as part of some kind of 'smart interlock' system. There is something to be said for interoperability between old and new equipment and being able to service and modify systems part by part.
 
Didn’t say it would be a listed combination, it was just above the heads of an average electrician that doesn’t understand controls. But it can be done, and it can interact with the pv and battery controls with an external controller.
"Average electricians"? There are plenty of jobs for them. If one wants to install the latest Enphase system ,you gotta get trained and pass certification in the Gen 4 Enphase IQ meter collar, Combiner 6C and 10C battery installation.
Enphase requires it.

BTW, it is a superior system in so many ways to its predecessors.

Simple answer to OP: this is not some jerry-rigged, no name product.
 
Frankly the meter collar strikes me as something that the residential ATS manufacturers should have come up with decades ago. We've seen pics here of hack work on meter mains to reroute busbars to a bulky ATS. That whole predicament isn't necessary.
It was a f$%^& nightmare trying to pull 2/0 conductors out of, and back into, a service panel.
 
Thanks again everyone the job went smooth.
I still think the MID looks silly, I'd prefer the MID to be in its own Enphase enclosure, the other Enphase enclosures are nice.
But its not my house and the customer was happy.
 
PG&E just moved from the collar as a special thing to a regular tariff with an install price. They insist that only PG&E may install the meter collars.
Here brothers and sisters is the heart of the matter. The utilities want to keep meter socket mounted transfer equipment as a profit center and allowing electricians to install them would cut into there exclusive access to that profit. Their claim of a safety concern is completely BOGUS!

Decades ago I had a client who had the manual version of the Generlink brand of meter socket mounted transfer switch which they had
used at their previous home. The utility's local field installation manager swore it would be a "Cold Day In Hell" before he would connect to the service because of the presence of the listed Generlink transfer switch being a hazard to his Linemen. He adamantly said that it could not be mounted on "their" meter socket. Like most meter sockets that Meter Socket Enclosure was mounted on the premises side of the State Utility Commission identified demarcation point. The demarcation point is that point in the electrical system were all control over the premise wiring system is in the hands of the premise owner.

The utility's problems were that the residential tariff did not give the supplying utility any control of the premises side of the Demarcation Point. They could only insist that the State Utility Commission approved service Standard be complied with. That utility's service standard only required that a transfer switch's utility connection be made on the load side of the meter or current transformers. The Generlink's manufacturer had gotten the product listed by complying with that practice. His refusal to connect also violated the Utility Commission's rules about requiring Commission permission to refuse to connect. His employing utility had not even applied for that.

I demanded that the refusal be provided in writing under the Seal and signatures of State recognized Corporation Officers as required by State law.. When he would not provide it I asked the Commission staff to intervene. By that time the AHJ's Chief Electrical Inspector was looking for blood. I had worked with him on some elderly home repair work and a Boy Scout Eagle project's supervision and he liked me. He was dammed if he was going to let the utility staff start undermining his inspectors. He got the Utility Commission to issue a subpoena for the required written refusal to connect permission application.

I needed to get paid in order to avoid serious financial hardship as I was a 1 man shop. So I came up with the idea to install a second meter socket enclosure right under the one that would hold the Utility owned meter. The Chief Electrical Inspector gave me written permission to do that. I then installed the the second meter socket, mounted the Generlink, inserted listed meter shunts, and a listed meter socket cover to avoid any need to insert a meter into the Generlink to complete the installation. I presented the signed off inspection report to the client and got paid. With money in hand I connected the client's 10,000 watt continuous rated generator to the Generlink and powered up their new home. Another member of the local Scout Master community installed a gas line from the meter tree to the generator's location to connect the clients tri fuel generator to Natural Gas with propane backup. Since I had been paid I went on to the next job with a deep sigh of relief.

Under pressure from the client's State Delegate and Senator the Utility Commission lit a fire under the utility's legal office and reminded them who it was that would approve, or not, their next rate increase request. Nothing is more persistent then a swarm of State Bureaucrats that one has carelessly made angry. All of a sudden the connection was made under the direct observation of a Utility Commission engineer.

I can assure all of you that I never made that mistake again. If this particular problem ever came up again I would have installed a cheap analog meter in the socket or waited until after the utility had connected before adding that meter socket. Like many of you a prolonged delay in getting paid would have hurt my family a lot. When I was single and didn't have such responsibilities I could get in regulatory battles any time I got my nose our of joint. I even did so a couple of times.
 
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