AFCI Compliance

NEC 2014 edition and 2017 edition National Electrical Code requires PV systems to have arc fault circuit interruption (AFCI) protection. AFCI protection is achieved by detection of an arc and immediate DC shutdown, at the string, combiner, or inverter level.

Some inverter manufacturers and other third-party devices have implemented solutions into their products, however some solutions experience false detection known as 'Nuisance Tripping'.

Being module-level (MLPE) devices, Tigo MLPE can not detect arc-fault, but some models can help mitigate damage.

There are 2 possible triggers  of AFCI, each results in DC disconnect:

1. Actual arc fault detected.
2. False detection, sometimes due to noise (rapid changes of voltage) on the string.  This 'noise' is sometimes interpreted as an arc fault, because the noise has similar characteristics as a real series arc generates, on voltage.

Tigo's TS4 models can be divided to 2 types, electrically:

• Electrically Passive:
  • TS4-D, TS4-M, TS4-R-M: are 100% electrically passive. This because only diodes or power measurement circuitry is involved.
  • Electrically, they behave just like PV modules without any MLPE device. Therefore, they can not produce voltage changes including 'noise' interpreted by AFCI detector. They can not cause false arc-fault detection.
• Electrically Active:
  • TS4-S, TS4-R-S, TS4-O, TS4-R-O, TS4-L, TS4-F and TS4-R-F
  • They perform disconnect, and O and L models optimize. Therefore, they can effect string voltage.
  • Both Tigo and independent third-parties testing is  performed to verify there are no false AFCI issues.
  • They are compatible with the vast majority of inverters with AFCI detection.

Research by Sandia National Laboratories investigated, and found multiple reasons for nuisance (false) arc-fault detection. Most causes were unrelated to optimization. Sandia Nation Labs Report is here.

Additional information:

https://support.tigoenergy.com/hc/en-us/articles/202368968-Inverter-Compliance

https://www.tigoenergy.com/downloads/inverter-compliance-letters/

https://www.sma-america.com/partners/knowledgebase/pv-arc-fault-circuit-interrupter.html

https://support.tigoenergy.com/hc/en-us/articles/225227067-SMA-Tigo-Compatibility-Guidelines

 

Support

f you have a specific question regarding an inverter equipped with AFCI that is not listed above, please email complete specific inverter model, and specific questions to: support@tigoenergy.com

Retired Products

*ES50, ES75, ES110 and ES170 are retired product since early 2013. The ES series was fully compatible with all the inverter technologies, which did not have Arc-fault detection at the time. As of the article creation date, they are not known to be compatible with modern inverters that have AFCI detection.

**2ES50, 2ES75 are retired products since mid 2016. The 2ES series was fully compatible with all inverter technologies and AFCI devices which were available on the market at the time of manufacturing.

Other Inverters with AFCI detection

Over time, more inverter models are being tested for AFCI compatibility.

As of February 4th 2019, Tigo has tested these inverter/optimizer combinations:

ABB Inverters with Tigo TS4-D/M/S/O/L

• ABB UNO-3.3-TL-OUTD-S-US
• ABB UNO-3.8-TL-OUTD-S-US
• ABB UNO-4.6-TL-OUTD-S-US
• ABB UNO-5.0-TL-OUTD-S-US
• ABB UNO-6.0-TL-OUTD-S-US
• ABB UNO-7.6-TL-OUTD-S-US
• ABB UNO-8.6-TL-OUTD-S-US

ABB Inverters with Tigo TS4-O/L

• Power-One PVI-4.2-OUTD-S-US-A

 

Canadian Solar (CSI) Inverters with Tigo TS4-O/L/F

• CSI-25KTL-GS-FLB
• CSI-30KTL-GS-FLB
• CSI-36KTL-GS-FLB
• CSI-40KTL-GS-FLB
• CSI-50KTL-GS-FLB
• CSI-50KTL-GS-B
• CSI-60KTL-GS-B
• CSI-66KTL-GS-B

 

Chint (CPS) Inverters with Tigo D/M/S/O/L

• CPS SCA23KTL
• CPS SCA28KTL
• CPS SCA36KTL
• CPS SCA50KTL
• CPS SCA60KTL

 

Delta Inverters with Tigo TS4-O/L

• M4-TL-US
• M5-TL-US
• M6-TL-US
• M8-TL-US

Delta Inverters with Tigo TS4-F

• M36U
• M42U
• M60U
• M80U

 

Fronius Inverters with Tigo TS4-O/L

• Fronius Galvo 2.5-1

Fronius Inverters with Tigo TS4-S/O/L

• Fronius Primo 8.2-1

 

Ginlong Solis Inverters with Tigo TS4-D/M/S/O

• Ginlong Solis Three Phase US
• Ginlong Solis Single Phase US
• Ginlong Solis Mini WW
• Ginlong Solis Three Phase WW
• Ginlong Solis Single Phase WW

Ginlong Solis Inverters with Tigo TS4-S/O/L

• Ginlong Solis Inverters Solis-5K-2G-US

 Ginlong Solis Inverters with Tigo TS4-O/L/F

• Solis-25K-US-SW
• Solis-30K-US-SW
• Solis-36K-US-SW
• Solis-40K-US-SW
• Solis-50K-US-SW
• Solis-50K-US-F-SW
• Solis-60K-US-F-SW
• Solis-66K-US-F-SW

 

Goodwe Inverters with Tigo TS4-D/M/S/O/L

• GW3000D-NS
• GW3600D-NS
• GW4200D-NS
• GW5000D-NS
• GW15K-DT
• GW17K-DT
• GW20K-DT
• GW25K-DT

 

Growatt Inverters with Tigo TS4-D/M/S/O/L

• Growatt 1000/1500/2000/2500/3000-S
• Growatt 2500/3000/3600/4200/5000/5500/6000 MTL-S
• Growatt SPH 3000/3600/4000/5000/6000
• Growatt 4000/5000/6000 UE
• Growatt SPH 4000/5000/6000/8000/10000/11000TL3-HV
• Growatt 7000/8000/9000/10000/11000TL3-S
• Growatt 12000/13000/15000TL3-S
• Growatt 12000/15000/18000/20000/25000 UE
• Growatt 30000/33000TL3-S
• Growatt 40000TL3-NS
• Growatt 50000TL3-S
• Growatt 1500/2000/3000-US
• Growatt 10000/12000/18000/20000TL3-US

Growatt Inverters with Tigo TS4-D/M/S/O/L/F

• Growatt 4000/5000/6000/7000/7600MTLP-US
• Growatt 8000/9000/10000MTLP-US
• Growatt 30000/33000/40000TL3-US

 

HiQ Inverters with Tigo TS4-D/M/S/O/L

• TrueString

 

Huawei Inverters with Tigo TS4-O/L

• SUN2000-30KTL

 

Ingeteam Inverters with Tigo TS4-O/L

• INGECON SUN 40TL U M480

 

Kaco Inverters with Tigo TS4-O/L

• KACO blueplanet 3.0TL1 M2 WMODUS39

 

Midnight Solar Inverters with Tigo TS4-D/M/S/O/L

• Classic Legacy P&O
• Classic Regular (Solar)

 

Outback Power with Tigo TS4-S

• FLEXmax 60
• FLEXmax 80
• FLEXware ICS Plus

 

SAJ Inverters with Tigo TS4-D/M/S/O/L

• Suntrio Plus
• Sununo Plus

 

SMA Inverters with Tigo TS4-D/M/S/O/L

• 5-1VL-40
• 5-1VL-40
• 0-1AV40
• 6-1AV40
• 0-1AV40
• 0-1AV40
• SB 3000TL-21
• SB 3600TL-21
• SB 4000TL-21
• SB 5000TL-21
• SB 6000TL-21
• 0-1SP-US-40
• 8-1SP-US-40
• 0-1SP-US-40
• 0-1SP-US-40
• 0-1SP-US-40
• 7-1SP-US-40
• SB 3000TL-US-22
• SB 3800TL-US-22
• SB 4000TL-US-22
• SB 5000TL-US-22
• SB 6000TL-US-22
• SB 7000TL-US-22
• SB 7700TL-US-22
• SB 3500TL-JP-22/MP
• SB 4500TL-JP-22/MP
• SB 5400TL-JP-22/MP
• STP 5000TL-20
• STP 6000TL-20
• STP 7000TL-20
• STP 8000TL-20
• STP 9000TL-20
• STP 10000TL-20
• STP 12000TL-20
• STP 15000TL-30
• STP 20000TL-30
• STP 25000TL-30
• STP 25000TL-JP-30
• STP 12000TL-US-10
• STP 15000TL-US-10
• STP 20000TL-US-10
• STP 24000TL-US-10
• STP 30000TL-US-10
• STP 10000TLEE-JP-10
• STP 10000TLEE-JP-11
• STP 50-40
• STP 50-US-40
• STP 50-JP-40
• STP 60-10
• STP 60-US-10
• STP 60-JP-10

SMA Inverters with Tigo TS4-D/M/S

• STP 10000TLEE-JP-10
• STP 10000TLEE-JP-11

SMA Inverters with Tigo TS4-O/L/F

• STP33 US-41 (w/ Tigo or native transmitter)
• STP50 US-41 (w/ Tigo or native transmitter)
• STP62 US-41 (w/ Tigo or native transmitter)

 

Solax Power Inverters with Tigo TS4-O/L/F

• A1-Hybrid-6.0-US
• A1-Hybrid-7.0-US
• A1-Hybrid-7.6-US
• A1-Hybrid-8.6-US
• A1-Fit-6.0-US
• A1-Fit-7.0-US
• A1-Fit-7.6-US
• A1-Fit-8.6-US

 

Sungrow Inverters with Tigo TS4-D/M/S/O/L

• SG2K5-S
• SG2K5-S
• SG2KTL-S
• SG2K-S
• SG3K-S
• SG3K-D
• SG3KTL-S
• SG3KTL-D
• SG3K6-D
• SG4K-D
• SG4K6-D
• SG5K-D
• SG5KTL-D
• SG6K-D
• SG10KTL-M
• SG12KTL-M
• SG36KTL-M
• SG60KTL
• SG80KTL
• SG125HV
• SG60KU-M

 

Yaskawa - Solectria Solar Inverters with Tigo TS4-D/M/S/O/L

• PVI 23TL with Arc firmware 5.0 or later
• PVI 28TL with Arc firmware 5.0 or later
• PVI 36TL with Arc firmware 5.0 or later
• PVI 3800TL
• PVI 5200TL
• PVI 6600TL
• PVI 7600TL
• PVI 50TL
• PVI 60TL