New Isolated PV- on FLEXpowers for FM100 AFCI

Discussion about the FM100 AFCI Charge Controller
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IanMcCluskey
OutBack Product Management
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Joined: Tue Aug 28, 2018 1:16 pm

New Isolated PV- on FLEXpowers for FM100 AFCI

Post by IanMcCluskey » Fri May 15, 2020 11:33 am

Happy Friday, forum community!

Sharing this post to spread knowledge about a key update to the PV negative wiring on new FLEXpower Radians with FM100 AFCI charge controllers. We have shipped hundreds of these since they were released earlier this year and installers have contacted us with questions about this change on two occasions so far.

The new FLEXmax 100 AFCI has built in arc fault detection, which works best when both positive and negative PV conductors are isolated. This prevents common mode noise from causing false arc fault trip events. Many OutBack users and installers are accustomed to the PV negative conductors landing on the common negative buss in Radian load centers. However, the new FLEXpower Radians land the PV conductors on separate bussbars within the load center to improve performance and prevent false trips.

We achieved this by using the box lugs on the PV breakers to land the PV positive input. This frees up the aforementioned PV input bussbars to be a separated negative connection for the negative PV input.

Please see the new quickstart guide for reference here: http://www.outbackpower.com/downloads/d ... 0_qsg.pdf
And in Spanish: http://www.outbackpower.com/downloads/d ... qsg_es.pdf

Thank you!
Ian McCluskey
Product Manager


Alpha Technologies Inc. / OutBack Power Technologies
3767 Alpha Way Bellingham WA 98226 USA
http://www.alpha.com

Mike Curran
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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 GVFX3524's classic stacked for 120/240VAC (2007)
- 12 Surrette/Rolls 2V x 1766Ah (2007)
- Hub10.3, Mate3s, FNDC, RTS, OpticsRE. Tigo Energy 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 (manual switch during grid outage only) from 14 Talesun 275W,
Enphase M215 microinverters, normally direct grid tied

All self-designed and self-installed
Location: Chagrin Falls, Ohio

Re: New Isolated PV- on FLEXpowers for FM100 AFCI

Post by Mike Curran » Sat May 16, 2020 8:38 am

Hey Ian - I'm curious, does the FM100's new built-in AFCI play nice with MLPE's? I only ask because the AFCI circuitry in my Skybox will not, and I'm wondering if Outback has found a way around that... - Mike
http://www.tigoenergy.com/site.php?95b2dca2-ca6c
https://enlighten.enphaseenergy.com/public/systems/Hctc107221

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IanMcCluskey
OutBack Product Management
Posts: 154
Joined: Tue Aug 28, 2018 1:16 pm

Re: New Isolated PV- on FLEXpowers for FM100 AFCI

Post by IanMcCluskey » Mon May 18, 2020 8:24 am

Hey Mike! Yes, the FM100 AFCI has an updated arc fault detection system. It is PVRSE listed with IMO FireRaptors, which OutBack sells, and with Tigo's TS4-S and TS4-F devices. We have ongoing tests with Tigo on their other devices, as well.
Ian McCluskey
Product Manager


Alpha Technologies Inc. / OutBack Power Technologies
3767 Alpha Way Bellingham WA 98226 USA
http://www.alpha.com

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