AC Coupling with GridBoss

[Skalawaggg]

I have recently purchased a house with grid tied solar already installed. I do not know the KWH output of the arrays yet, but I am curious as to why I have 4 separate 20A breakers for the solar. I’m assuming this means I have 4 total arrays?
My question is what would need to be done in order to AC couple the whole system? Is each array on seperate microinverter chains? Is there a way to tie them all together without having to get new micro inverters?
I want to be able to use all the solar, im thinking smart port on something like a GridBoss and then one or two flexboss and one to two wall mount battery arrays.

Does anyone know why I would have the 4 seperate breakers for the solar and how I can tie them all together so they act as a single source?

 

[BentleyJ]

First thing that comes to mind with 4 breakers is safety and possible code violations. Was this a permitted system with permission to operate from the utility?
When connecting a second source of power to a breaker panel the 120% rule applies. For example a standard 200A main panel can support up to a 40A breaker with grid-tie solar and a 200A panel with 225A bus bars can support up to a 70A solar breaker.

If your present system has a total of 80A of solar breakers the panel would have to have greater than 225A bus bars or perhaps a derated main breaker. Its also possible that 20A solar breakers were used but each of the 4 strings is not utilizing all of the breaker capacity. Based on the above further investigation is absolutely necessary to identify the PV panel brand and model number as well as the inverters and the system STC output rating.

As to your question, The 4 x 20A breakers could most likely be condensed by using a combiner box. This is a common practice with Enphase microinverters where 2+ strings of microinverters are fed into a combiner box so each string has its own breaker then the breakers are tied together on a common bus bar then out to the main panel that has only 1 larger solar breaker.

 

[Quattrohead]

We need more details, is it an enphase or solaredge system or some random DIY. Some pictures will be mighty helpful.

 

[Skalawaggg]

I will have more info in a couple days, have the name of the install company. I do know it was permitted and we had to sign paperwork to switch power into my name that it was a net meter system so it is all legit, I’m just confused as to how I arrange all the solar to feed into one smart port of GridBoss so that I can ac couple a hybrid inverter and use my solar to charge batteries when grid is down.
I also have a smart box that is supposed to show me all the info about solar like how many KWH they are generating etc. I need to get internet switched over so that I can plug the smart box in.
We are in the process of moving but I should have the needed info soon

 

[Quattrohead]

Sounds like it is an Enphase system and probably quite big if it's using four circuit breakers for the strings. You will then have a single output that you will be able to AC couple into a hybrid inverter that you can add batteries etc to.

 

[Lawrence_SoCal]

Just an FYI... for a 8kW enphase based AC-coupled grid tie solar system with 425W panels, each approx 10 panels is it own 20A breaker, and then common to have mgmt gateway/envoy (or PVS if SPWR) on its own breaker, sometimes in sub-panel if main load center full (or simply to make overall operations/isolation easier. If using sub-panel, then another dual-pole 240V breaker for connection to main load center

So you'd want to know number of panels, and ideally version (model) panel (primarily the wattage rating)

if all those solar circuits are micro-inverter based panels (ie AC-coupled) and all of those in main load center... then typical solution would be to re-locate the solar circuits (and management/monitoring device) into a sub-panel, and route that sub-panel to the GridBOSS.

As GridBOSS and hybrid inverters are not known have having lifespans = old circuit breakers (ie many decades)... but instead more like hot wat4er heaters... it is prudent to wire these (even gridBOSS) with a bypass/transfer switch, so if/when it fails in X years, you can bypass while awaiting repairs/replacement... In this case, I'd consider a switch to route solar sub-panel to GridBOSS or direct to main load center, just as I'd have for meter feed to GridBOSS (or any similar device).
My thinking... consider scenario where hybrid inverter/gateway device (GridBOSS) fails while you are away on a trip (significant other, kids, whomever still at house). What then? I'm thinking paying a little more upfront to be able to have simple instructions of turn these breakers off, flip these switches, in this order, and house is back and operating, solar still producing, etc.. = highly desirable [laminate instructions, or put in plastic sleeve, with pictures, etc ... as 'dummy proof' as practical]. Also consider similar scenario and no one home. I'd want to avoid a setup where batteries could get ruined (drained and left drained), freezer (well pump? heaters?) not working, etc. just things to think thru

 

[Usernameinuse]

Gridboss has a manual bypass that has no circuitry, just copper. Even if all other components fail, it will still work.