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![Feeder – 10 Ft. Tap
705.12(D)(2)(2)
PV – 160A
Continuous
Minimum Feeder Tap
[200A + (160A x 1.25)] x .10 = 40A, but
in no case less than the rating of the
100A OCPD
225A
100A
200A
200A
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.
. .. .
. .
. .. .
100A
200A
225A
3 AWG rated
100A33 75ºC
at
LOAD
LOAD
30A
20A
200A
1000A Bus
200A
20A
20A
15A
LOAD
LOAD
LOAD
200A
400A
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..
..
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. .
. .. .
. .. .
30A
50A
50A
50A
50A
LOAD
LOAD
LOADS
100A Bus
400A Bus
Feeder tap between the feeder overcurrent protection device and the
inverter AC output protection device, must have an ampacity not less than
the feeder overcurrent protection device, plus 125% of th e inverter output
AC circuit current rating in accordance with 240.21(B).](https://image.slidesharecdn.com/121913moocslidesforrichardfinal-131221113112-phpapp02/85/Changes-to-2014-NEC-Interconnection-Rule-705-12-11-320.jpg)
More Related Content
Changes to 2014 NEC Interconnection Rule 705.12
- 1. 705.12(D) Point ofConnection Utility Interactive Inverters By Richard Stovall, CEO SolPowerPeople #SolarMOOC Webinar 12/19/13 12PM CST
- 2. 705.12(D)(1) This change ismeant to accommodate microinverters and AC module systems where there may be more than one inverter feeding one OCPD.
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- 5. 2014: Utility InteractiveInverters Feeder Conductor Ampere Rating 705.12(D)(2)(1)(a) 225A 100A 200A 400A . .. . .. .. PV – 160A Continuous . . 200A MLO 200A 200A 200A 200A + (160A x 1.25) = 400A 600kcmil 225A 30A 50A 200A 1000A Bus 200A, 3/0 AWG rated at 200A at 75ºC, Table 310.15(B)(16) 50A . . .. .. 50A 50A 400A Bus The feeder conductor on the load side of the inverter AC output connection must have an ampacity not less than the feeder overcurrent protective device, plus 125% of the inverter output AC circuit rating.
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- 8. PV – 160A Continuous 100A 225A 200A 1000ABus 200A 200A 200A 225A 200A 200A 200A 400A . .. . .. .. . . .. . 2014: Utility Interactive Inverters Feeder Conductor Ampere Rating 705.12(D)(2)(1)(b) 200A, 3/0 AWG rated at 200A at 75ºC, Table 310.15(B)(16) 200A Bus The feeder conductor on the load side of the inverter AC output connection must have overcurrent protection on the load side of the inverter output AC connection sized not greater than the ampacity of the feeder.
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- 11. Feeder – 10Ft. Tap 705.12(D)(2)(2) PV – 160A Continuous Minimum Feeder Tap [200A + (160A x 1.25)] x .10 = 40A, but in no case less than the rating of the 100A OCPD 225A 100A 200A 200A . . . .. . . . . .. . 100A 200A 225A 3 AWG rated 100A33 75ºC at LOAD LOAD 30A 20A 200A 1000A Bus 200A 20A 20A 15A LOAD LOAD LOAD 200A 400A . .. . .. .. . . . . . . .. . . .. . 30A 50A 50A 50A 50A LOAD LOAD LOADS 100A Bus 400A Bus Feeder tap between the feeder overcurrent protection device and the inverter AC output protection device, must have an ampacity not less than the feeder overcurrent protection device, plus 125% of th e inverter output AC circuit current rating in accordance with 240.21(B).
- 12.
- 13. Taps not over10ft long • 240.21(B)(1)
- 14. Feeder – 25Ft. Tap 705.12(D)(2)(2) PV – 160A Continuous Minimum Feeder Tap Size [200A + (160A x 1.25) x .33 = 133A . . 200A 225A 100A . . . .. . . . . .. . 100A 200A 225A 1/0 AWG rated 33 150A at 75ºC LOAD LOAD 30A 20A 200A 1000A Bus 200A 20A 20A 15A LOAD LOAD LOAD 200A 400A . .. . .. .. 200A . . . . .. . . .. . 30A 50A 50A 50A 50A LOAD LOAD LOADS 100A Bus 400A Bus Feeder tap between the feeder overcurrent protection device and the inverter AC output protection device, must have an ampacity not less than the feeder overcurrent protection device, plus 125% of the inverter output AC circuit current rating in accordance with 240.21(B).
- 15.
- 16. Taps not over25ft long • 240.21(B)(2)
- 17. EC&M Article onFeeder Taps • Written by Mike Holt • http://ecmweb.com/code-basics/feeder-taps
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- 20. 2011 Code isbased on the OCPD of the inverter. Therefore the MAX OCPD fed to this panel in this location is 25A: 225A(busbar rating) minus 200A (main breaker rating) = 25A 200A MAIN PV 25A OCPD 225A BUS
- 21. 2014 Code isbased on the 125% of the inverter continuous output current. Is there a difference? Yes. There may be more design flexibility with the new rule. 200A MAIN PV SUPPLY OCPD PV SUPPLY OCPD 225A BUS
- 22. Example: 2 branchmicroinverter circuits. With 25A max (inverter continuous output x 125%) Assuming M215 (215Wac) that’s 22 inverters: (25A/(215/240*1.25)=22.32 200A MAIN PV SUPPLY OCPD PV SUPPLY OCPD 225A BUS
- 23. Example: 22 microinverterswith allowable 20A OCPD per circuit (11 each). In 2011 Code this is not allowable because it violates the 25A max OCPD requirement. 200A MAIN PV 20A OCPD PV 20A OCPD 225A BUS
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- 26. 2011 Code isbased on the OCPD of the inverter. Therefore the MAX OCPD fed to this panel in this location is 70A: 1.2 X 225A(busbar rating) minus 200A (main breaker rating) = 70A 200A MAIN PV 70A OCPD 225A BUS
- 27. 2014 Code isbased on the 125% of the inverter continuous output current. Is there a difference? Yes. There may be more design flexibility with the new rule. 200A MAIN PV SUPPLY OCPD 225A BUS
- 28. Example: 4 branchmicroinverter circuits. With 70A max (inverter continuous output x 125%) Assuming M215 (215Wac) that’s 62 inverters: (70A/(215/240*1.25)=62.51 200A MAIN PV 20A OCPD PV 20A OCPD PV 20A OCPD PV 20A OCPD 225A BUS TOTAL: 80A PV OCPD, OKAY IN 2014 CODE
- 29. Example: 62 microinverterswith 20A OCPD per circuit (15 X 2 and 16 x 2). In 2011 Code this is not allowable because it violates the 70A max OCPD requirement. 200A MAIN PV 20A OCPD PV 20A OCPD PV 20A OCPD PV 20A OCPD 225A BUS
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- 31. 200A MAIN 20A 2-POLE PVOCPD 25A 2-POLE EMPTY 20A 2-POLE PV OCPD 15A 1-POLE 60A 2-POLE 30A 1-POLE 20A 2-POLE PV OCPD 50A 2-POLE 225A BUS
- 32. LINE A LINE B 25 25 20 20 20 20 20 20 50 50 60 60 30 15 225 210 200AMAIN 20A 2-POLE PV OCPD 25A 2-POLE EMPTY 20A 2-POLE PV OCPD 15A 1-POLE 60A 2-POLE 30A 1-POLE 20A 2-POLE PV OCPD 50A 2-POLE 225A BUS
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- 38. NOT SUITABLE FORBACKFEED LOAD LINE
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- 41. THANK YOU!! • • • • • Richard Stovall CEOSolPowerPeople rstovall@solpowerpeople.com 512-825-3051 www.solpowerpeople.com