Battery charging during grid outage

True Hybrid Energy System
Post Reply
User avatar
Mike Curran
Forum Emperor
Posts: 2477
Joined: Sat Aug 28, 2004 6:28 pm
My RE system: Outback - Garage roof:
- 8 (2x4) Evergreen 180's into one FM80 (2007/2020 - replaced MX60)
- 6 (2×3) ALEO S79-300's into one FM80 (2017)
- 2 grid-tied VFXR3524A-01's series stacked, replaced GVFX's (2020)
- 12 Surrette/Rolls 2V x 1766Ah (2007)
- Hub10.3, Mate3s, FNDC, RTS. Tigo ES maximizers on each PV module.

Westinghouse Solar - Barn roof: (2012)
- 30 (2x15) 235W panels with Enphase M215 microinverters, grid-tied

Outback Skybox - Barn roof: (2019)
- 14 Talesun 275W in series (DC array input to SB inverter/charger)
- 3 SimpliPhi 3.8 batteries, 48V, 225Ah total
- AC coupled input from 14 Talesun 275W, Enphase M215 microinverters

Battery systems operate in grid-tied, battery backup mode
All self-designed and self-installed
Location: Chagrin Falls, Ohio

Battery charging during grid outage

Post by Mike Curran »

This past Saturday I had a grid outage from 12:30 to 4:30pm. There was plenty of sun during the outage but my Skybox was only allowing a minimum of charging current from my DC array, not even enough to maintain SOC at 100% despite my load being extremely small (max 70W or so). And my AC-coupled array was not contributing anything at all.
Screenshot_20210720-121030_Samsung Internet.jpg
Note in the screenshot, during the outage, dark red bars are energy from battery, light red are load, and light green is solar (DC PV).

I'm thinking that Skybox is maybe waiting for SOC to reach the programmed minimum before initiating a charge, but I'm puzzled as to why, in a system set up as grid-tied with battery backup, my Skybox didn't use the available solar to maintain my battery. It just seems that in an outage you would want to utilize all the solar that's available, at least until nightfall...

Anybody have a clearer understanding of Skybox operation during grid outages?
https://smart.tigoenergy.com/p/pZXn7SZQyO45?date=2021-04-19
https://enlighten.enphaseenergy.com/public/systems/Hctc107221
raysun
Forum Emperor
Posts: 5617
Joined: Tue Jul 26, 2016 5:57 am
My RE system: Flexpower Two: (2) FXR3048A-01, (2) FM80, MATE3s, FlexNetDC
SimpliPhi 48-3.8 (6 @ 48v)
Outback IBR3 battery enclosure
REC Alpha 440W panels - 2 arrays: each of 4 strings of 2 in series
Honda EU7000is gas fuel generator

Re: Battery charging during grid outage

Post by raysun »

Hey Mike,

Of course, I have nothing to offer to the Skybox conversation, but it sure sounds like Outback needs to put a couple of engineers in front of a Skybox webinar so all you early adopters can get functional answers to real-world questions.

There seems to be an awful lot of: "Skybox works great, I just can't quite figure out what its doing".
Photon Kapture
Forum Member
Posts: 19
Joined: Tue Jan 14, 2020 4:54 pm
My RE system: 3.9 Kilowatt (13) Solar World sw300 Array.
Outback Skybox
(3) Simpliphi Lithium Iron Phosphate Batteries (2) 3.5 and (1) 3.8KWH
Location: Schroeder, Minnesota

Re: Battery charging during grid outage

Post by Photon Kapture »

Mike,

Was your skybox still in bulk charging when the grid went down?

I use Skybox off grid. It initiates charge as soon as there is enough solar first thing in the morning, every day, regardless of battery voltage. While it’s charging, any loads reduce the charging power. Once it completes the charge it only sends PV through to cover loads through the rest of the day. Battery power supplements the load if it is more than the available PV power. And then battery takes over when the solar isn’t available. I don’t think this answers your question… :grin:

Maybe the behavior is different if you are in another grid mode when the grid goes down.

I agree with Raysun- we really could use more education on the Skybox behaviors in different situations.
raysun
Forum Emperor
Posts: 5617
Joined: Tue Jul 26, 2016 5:57 am
My RE system: Flexpower Two: (2) FXR3048A-01, (2) FM80, MATE3s, FlexNetDC
SimpliPhi 48-3.8 (6 @ 48v)
Outback IBR3 battery enclosure
REC Alpha 440W panels - 2 arrays: each of 4 strings of 2 in series
Honda EU7000is gas fuel generator

Re: Battery charging during grid outage

Post by raysun »

we really could use more education on the Skybox behaviors in different situations.
I don’t/won't own a skybox but want to attend that webinar.

Maybe we need a "communications campaign". I suggest we find the PiC (person in charge) of such things within the Organization and send a request, via email perhaps.

Or torches and pitchforks.
😉
User avatar
Mike Curran
Forum Emperor
Posts: 2477
Joined: Sat Aug 28, 2004 6:28 pm
My RE system: Outback - Garage roof:
- 8 (2x4) Evergreen 180's into one FM80 (2007/2020 - replaced MX60)
- 6 (2×3) ALEO S79-300's into one FM80 (2017)
- 2 grid-tied VFXR3524A-01's series stacked, replaced GVFX's (2020)
- 12 Surrette/Rolls 2V x 1766Ah (2007)
- Hub10.3, Mate3s, FNDC, RTS. Tigo ES maximizers on each PV module.

Westinghouse Solar - Barn roof: (2012)
- 30 (2x15) 235W panels with Enphase M215 microinverters, grid-tied

Outback Skybox - Barn roof: (2019)
- 14 Talesun 275W in series (DC array input to SB inverter/charger)
- 3 SimpliPhi 3.8 batteries, 48V, 225Ah total
- AC coupled input from 14 Talesun 275W, Enphase M215 microinverters

Battery systems operate in grid-tied, battery backup mode
All self-designed and self-installed
Location: Chagrin Falls, Ohio

Re: Battery charging during grid outage

Post by Mike Curran »

Photon Kapture wrote: Tue Jul 20, 2021 3:45 pm Was your skybox still in bulk charging when the grid went down.
No - made absorb parameters (55.0V for my system) around 6:00am.
Screenshot_20210720-193113.jpg
https://smart.tigoenergy.com/p/pZXn7SZQyO45?date=2021-04-19
https://enlighten.enphaseenergy.com/public/systems/Hctc107221
Post Reply