Meter socket adapters?

P

pipe_bender

Senior Member
Location
Boston
Occupation
Electrician
A customer has a existing Enphase solar system and wants to add a small Energy storage system to use their solar during an outage, to do this I recently learned about a type of ATS called a Microgrid Interconnect Device (MID) [defined in the code] Its basically a automatic 200A disconnect rather than 'transfer', think of a ATS with no generator landed.
Their solar person is proposing to use a goofy looking 'meter socket adapter' despite not being allowed by our utility.
They want an electrical contractor (me) to install a 'separate meter can downstream of the utility meter'.
I dont know why they even bother with this, seems like a hack to me, so I am asking you experts your thoughts on this
Here is the unit:
https://enphase.com/download/iq-meter-collar-data-sheet
What would you do here and if you have installed one how well do these things work?
I am not familiar with Enpahse products and their site is so full of fluff its unusable, do any of you more up to date with Enphase people know if they have a 3R ATS like enclosure or 'stand alone MID' product that does not make me look like a clown?
I take it they dont, as they are pushy about this, but I'd love to be worng.

Then I noticed it takes a 24V control cable, and in the past I have done controls for commercial ATS's that mix and match brands so I got thinking can I use the Enphase 24V with a off the self 200A ATS?

Thanks everyone for reading.
 
Last edited:
I haven't seen a lot of those things, but from a quick glance online they don't seem to be cheap. More money for crappier results?

Or the guy makes a nice profit on selling them, he might even already have some he got cheap somewhere. If you have cherry pies to sell, the best pie in the world is cherry
 
Enphase is the leading residential solar inverter manufacturer. What the client is proposing will absolutely work, although a backup loads panel needs to be installed on the load side of the meter collar socket. I have done it twice since the product was released earlier this year, not to mention a dozen or so additional installs with utility installation at their socket.

The idea to use a third party ATS will not work. That completely misunderstands the point.

hillbilly1 said:
Not going to be easy, if they are selling power back to the utility, the inverter will automatically shutdown upon loss of utility.
Click to expand...
Incorrect. The meter collar provides the functionality to operate in stand-alone mode. (Also anti-islanding functionality has nothing to do with selling power to the grid, per se.)
 
pipe_bender said:
...do any of you more up to date with Enphase people know if they have a 3R ATS like enclosure or 'stand alone MID' product that does not make me look like a clown?
Click to expand...

The meter collar is the stand-alone MID for the latest system. Why would you want some big ATS enclosure instead of a little meter socket? It doesn't look too clownish with the jumper cover (https://enphase.com/store/accessories/jumper-cover) which they sell for much less than the manufacturer.
 
jaggedben said:
Enphase is the leading residential solar inverter manufacturer. What the client is proposing will absolutely work, although a backup loads panel needs to be installed on the load side of the meter collar socket. I have done it twice since the product was released earlier this year, not to mention a dozen or so additional installs with utility installation at their socket.

The idea to use a third party ATS will not work. That completely misunderstands the point.


Incorrect. The meter collar provides the functionality to operate in stand-alone mode. (Also anti-islanding functionality has nothing to do with selling power to the grid, per se.)
Click to expand...
So it’s made for solar? I thought it was one of those made for generator type. So the the 24 volt signal puts it into island mode? Anti island mode prevents back feed to a dead utility, and the only way you could sell back is to connect to utility, so that statement is incorrect.
 
hillbilly1 said:
So it’s made for solar? I thought it was one of those made for generator type.
Click to expand...
It's made specifically for use with other Enphase products, mainly in Enphase 4th gen battery backup system, with the Combiner 6C and 10C battery. Are there meter collars for generators? I haven't heard of those.
hillbilly1 said:
So the the 24 volt signal puts it into island mode?
Click to expand...
No the 24V is always on. It provides power from the batteries to the meter collar and combiner in case the line voltage is not present. It is not used for signalling AFAIK (there are two other conductors in the cable for coms).
hillbilly1 said:
Anti island mode prevents back feed to a dead utility, and the only way you could sell back is to connect to utility, so that statement is incorrect.
Click to expand...
Not sure what statement you're calling incorrect, but when an MID takes over anti-islanding duties, multi-mode inverters can keep going without a primary source (utility) voltage reference.
Also anti-islanding doesn't care where the utility meter is, or even if there is one, or if one gets paid for backfeeding energy. "Selling" does care about those things. Anti-islanding is still in play even when there's no selling.
 
Last edited:
hillbilly1 said:
Yes, it can work, but an in depth understanding of controls would be needed. Not for the average electrician to do.
Click to expand...
Perhaps installing/reconfiguring a 100-200A feeder (and moving loads to a backup panel?) is not for the average solar installer to do, hence they want help. (I mean, my company has been doing it for years, but we're not average. ;))

OP is being asked to do a scope of work. Solar installer has the skills and responsibility to commission the system and make it work. OP is asking for a sanity check, and I'm giving them one. The scope of work makes sense and might lead to ongoing opportunities to get more work through this solar guy.
 
hillbilly1 said:
Yes, it can work, but an in depth understanding of controls would be needed. Not for the average electrician to do.
Click to expand...
No, it will not work. An ATS would only allow either utility power or PV/battery power to be used, not all 3 together.

A MID device does not transfer loads to a different source. It simply opens up one of the sources (utility) when power is not present and allows the other 2 power sources to keep working.
 
Enphase used to supply a stand alone MID device, size wise similar to a transfer switch. This requires an electrician making expensive modifications to intercept the supply between the utility and the house panel. They recently launched the meter collar MID to eliminate the additional electrical modifications in most cases.

Many utilities are allowing the collars to be installed behind their meters. For those that don't approve them yet or if you only want to do a partial backup you install a separate meters socket.
 
curt swartz said:
No, it will not work. An ATS would only allow either utility power or PV/battery power to be used, not all 3 together.

A MID device does not transfer loads to a different source. It simply opens up one of the sources (utility) when power is not present and allows the other 2 power sources to keep working.
Click to expand...
Yes it will work. It is doing the exact same thing a transferswitch does, the only difference is it has a built in control to make the inverter go island mode. Without control modifications, no a standard transferswitch would not work, but with modifications, it would work exactly the same.
 
hillbilly1 said:
Yes it will work. It is doing the exact same thing a transferswitch does, the only difference is it has a built in control to make the inverter go island mode. Without control modifications, no a standard transferswitch would not work, but with modifications, it would work exactly the same.
Click to expand...
If all of the PV and batteries are connected to the load of the switch, nothing connected to the generator inputs, then yes it would technically drop off the utility. It would not interact/communicate with the PV and battery controls and provide information such as consumption data.

It would definitely not be a listed combination so no warranty on system from manufactures or passing AHJ inspections.
 
Deltaforce said:
If no cost advantage, any other advantage?
Click to expand...
Not sure what you are asking.

The Enphase meter collar is definitely less expensive for adding batteries to existing homes since ti does not require an reconfiguring of the existing feeders or service conductors. The solar contractor simply runs a 4/C TC cable from the Combiner to the meter collar and the utility plugs the meter collar in.

If the utility does not accept the meter collars or if partial backup is desired the material/labor cost to install a meter socket and adapter is about the same as installing a traditional MID device.

Enphase could offer the option of a traditional MID device when the utility doesn't accept the Collars but when you can simply install the collar on the off the shelf meter socket to get the same thing it doesn't make sense to design, support and stock 2 parts.
 
curt swartz said:
If all of the PV and batteries are connected to the load of the switch, nothing connected to the generator inputs, then yes it would technically drop off the utility. It would not interact/communicate with the PV and battery controls and provide information such as consumption data.

It would definitely not be a listed combination so no warranty on system from manufactures or passing AHJ inspections.
Click to expand...
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.
 
hillbilly1 said:
Yes it will work. It is doing the exact same thing a transferswitch does, the only difference is it has a built in control to make the inverter go island mode. Without control modifications, no a standard transferswitch would not work, but with modifications, it would work exactly the same.
Click to expand...
A standard transfer switch could only control an inverter as part of listed combination of equipment that provides UL1741 anti-islanding. I'm unaware of any systems that support using an off-the-shelf ATS this way. For residential work this is not a very feasible idea. You could design a system this way with some inverters, I've seen listed and factory assembled combinations even; it's an inefficient, rube-goldberg kind of setup, with more conductors and moving parts than necessary. What Enphase is doing is much easier to install, less expensive, and more easily serviced.
Deltaforce said:
Separate meter make MID arrangement more costly. If utility approve, integration with utility meter, cost effective
Click to expand...
Deltaforce said:
If no cost advantage, any other advantage?
Click to expand...

A separate meter socket makes the arrangement somewhat more costly than installing at the utility meter, yes, but not more costly than other separate MID arrangements (such as the Enphase System Controller or the original Tesla Gateways, etc.). Separate MIDs (i.e. not bundled with inverters) provide a lot more flexibility for certain installation situations. For example if the energy storage system needs to be installed at a remote location from where you'd like to have the MID for a 100-200A feeder or service. Instead of running the 100-200A feeder to the ESS location and back, you just run the ~40-80A ESS circuit; saves a lot of cost if it has to go some distance. Also decouples the MID SKU from the inverter SKU, which is helpful from a logistics and inventory management point of view.
curt swartz said:
Enphase used to supply a stand alone MID device, size wise similar to a transfer switch. ...
Click to expand...
This will still be available for a while.
 
The meter collars are very utility specific.
Check first! In my area 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.

Collars come in all sorts of types: utility and load side taps, breakers, transfer, etc, etc etc.
 
You must log in or register to reply here.
Top