Student Resource Building University of California Santa Barbara Clement Fung Lighting Electrical Option APPENDIX E Electrical System Single Line Diagram Overcurrent Protection Study Overcurrent Protection Device Specifications
Overcurrent Protection and Coordination Main Switchboard (MS) Panel HAa Panel HA Panel HA Feeder to HA Breaker (A) 60 % of Rated Current Actual Current (A) Time(s) Actual Current (A) Time(s) Actual Current (A) Time(s) Actual Current (A) Time(s) Actual Current (A) Time(s) 00 00 60 00 00 00 7 70 4 40 4 80 7 4 8 6 40 4 6 0 0 4 7 7 60 0.8 9 4 0.9 480 0.7 0 Breaker (A) Transformer TA (primary) Transformer TA (secondary) Feeder to Panel LAa % of Rated Current Actual Current (A) Time(s) Actual Current (A) Time(s) Actual Current (A) Time(s) 00 4 00 00 690 70 40 4 40 8 80 7 0 7 7 9 7 70 6. 0 760 0.04 0.04
00 0 0 0 Time-Current Curves For Branch Circuit Protection "Path B-C-D-E" 0 00 Current (A) A A A 60A A Time (Seconds)
00 0 0 0 Time-Current Curves For Branch Circuit Protection "Path B--" 0 00 Current (A) A A A A Time (Seconds)
9-67N Page Types ND, CND, HND, CHND, NDC, CNDC Equipped With Type NES Digitrip RMS Trip Units With Adjustable Short Time Delay (Phase Protection) CURRENT IN MULTIPLES OF RATING PLUG AMPERES (I n ).6.7.8.9 4 6 7 8 9,000 MINUTE HOUR HOURS,000,000 Long Delay➀ Minimum Total Clearing Time Standard Plug X Long Delay➀ Maximum Total Clearing Time 4X 6X 7X 8X Short Delay Pick Up Settings (Tolerance ±%) Circuit Breaker Time/Current Curves (Phase Current) Series C N-Frame Circuit Breakers Equipped With Type NES Digitrip RMS Trip Units The NES Digitrip RMS Trip Units are AC only devices that employ microprocessor based technology that provides true RMS current sensing means for proper correlation with thermal characteristics of conductors and equipment. They are used with Circuit Breaker Types ND, CND, HND, CHND, NDC, and CNDC. Adjustable Short Time Delay Frame Amperes (Max.) Available Plugs Ampere Type (In) 6 4,,,,, 6, 0 6,, 0, Interrupting s /60 Hz RMS Sym. Amperes (ka) Breaker Type ND, CND HND, CHND NDC, CNDC Digitrip RMS Plug Push Cat. to /n Trip Y Engaged Remove Adj. Adj. Adj. UL/CSA 40V 480V V Catalog Number 8NEST 8NEST 8NES6T➃ 8NEST 8NEST 8NEST 8NES4T 8NEST A8NEST A8NEST➃ NEST NES0T NEST➃ NEST NEST NES6T➃ NEST ANEST Short Delay Pickup Range Amperes -6-60-40-4 -4 0-0 - - -6-6 -9 0-0 -7-6 - 60-40 -4-9 Notes Curve accuracy applies from - C to + C ambient. For possible ampere derating for ambient above 40 C, refer to Cutler-Hammer. Digitrip RMS trip units are suitable for functional field testing with test kit Cat. No. STK. For field testing using primary injection methods, follow NEMA publication AB-4-99. For ground fault time-current curves see SC-77-9A. ➀ There is a memory effect that can act to shorten the long delay. The memory effect comes into play if a current above the long delay pick up value exists for a time and then is cleared by the tripping of a downstream device or the circuit breaker itself. A subsequent overload will cause the circuit breaker to trip in shorter time than normal. The amount of time delay reduction is inverse to the amount of time that has elapsed since the previous overload. Approximately five minutes is required between overloads to completely reset the memory. ➁ For high fault current levels a fixed instantaneous override is provided at 0A (Tolerance ±%). ➂ The end of the curve is determined by the interrupting rating of the circuit breaker. See above tabulation. ➃ Not UL/CSA Listed. Typical Trip Unit Nameplate Short Delay Pickup x In 4 6 TEST Digitrip RMS 7 Trip Unit 8 40 C Ambient IEC 947- -40V 80-4V ICS = ICU ICW = ka @ S Uimp = 8kV X X MS. MS MS I Instantaneous Overide➁ SECONDS Interrupting Determines End of Curve➂.00.6.7.8.9 4 6 7 8 9 CURRENT IN MULTIPLES OF RATING PLUG AMPERES (I n ).00,000,000,000 40,000,000 CURRENT IN AMPS 60,000 70,000 80,000 90,000,000,000 Curve No. SC-76-9A October 997
9-67N Page Types ND, CND, HND, CHND, NDC, CNDC Equipped With Type NES Digitrip RMS Trip Units With I t Ramp Short Time Delay (Phase Protection) CURRENT IN MULTIPLES OF RATING PLUG AMPERES (I n ).6.7.8.9 4 6 7 8 9,000 MINUTE HOUR HOURS,000,000 Long Delay➀ Minimum Total Clearing Time Standard Plug X Long Delay➀ Maximum Total Clearing Time X 4X Short Delay Pick Up Settings (Tolerance ± %) Circuit Breaker Time/Current Curves (Phase Current) Series C N-Frame Circuit Breakers Equipped With Type NES Digitrip RMS Trip Units The NES Digitrip RMS Trip Units are AC only devices that employ microprocessor based technology that provides true RMS current sensing means for proper correlation with thermal characteristics of conductors and equipment. They are used with Circuit Breaker Types ND, CND, HND, CHND, NDC, and CNDC. I t Ramp Short Time Delay Frame Amperes (Max.) Available Plugs Ampere (In) 6 4,,,,, 6, 0 6,, 0, Interrupting s /60 Hz RMS Sym. Amperes (ka) Breaker Type ND, CND HND, CHND NDC, CNDC Digitrip RMS Plug Push Cat. to /n Trip Y Engaged Remove Type Adj. Adj. Adj. Typical Trip Unit Nameplate Short Delay Pickup x I n 4 6 TEST Digitrip RMS 7 Trip Unit 8 40 C Ambient UL/CSA 40V 480V V Catalog Number 8NEST 8NEST 8NES6T➃ 8NEST 8NEST 8NEST 8NES4T 8NEST A8NEST A8NEST➃ NEST NES0T NEST➃ NEST NEST NES6T➃ NEST ANEST Short Delay Pickup Range Amperes -6-60-40-4 -4 0-0 - - -6-6 -9 0-0 -7-6 - 60-40 -4-9 IEC 947- -40V 80-4V ICS = ICU ICW = ka @ S Uimp = 8kV Notes Curve accuracy applies from - C to + C ambient. For possible ampere derating for ambient above 40 C, refer to Cutler-Hammer. Digitrip RMS trip units are suitable for functional field testing with test kit Cat. No. STK. For field testing using primary injection methods, follow NEMA publication AB-4-99. X 6X 8X For ground fault time-current curves see SC-77-9A. ➀ There is a memory effect that can act to shorten the long delay. The memory effect comes into play if a current above the long delay pick up value exists for a time and then is cleared by the tripping of a downstream device or the circuit breaker itself. A subsequent overload will cause the circuit breaker to trip in shorter time than normal. The amount of time delay reduction is inverse to the amount of time that has elapsed since the previous overload. Approximately five minutes is required between overloads to completely reset the memory. ➁ For high fault current levels a fixed instantaneous override is provided at 0A (Tolerance ±%). ➂ The end of the curve is determined by the interrupting rating of the circuit breaker. See above tabulation. ➃ Not UL/CSA Listed. 7X. Instantaneous Overide➁ SECONDS Interrupting Determines End of Curve➂.00.6.7.8.9 4 6 7 8 9 CURRENT IN MULTIPLES OF RATING PLUG AMPERES (I n ).00,000,000,000 40,000,000 CURRENT IN AMPS 60,000 70,000 80,000 90,000,000,000 Curve No. SC-7-9A October 997
9-67L Page Types LDB, LD, HLD Equipped With Type LT Thermal-Magnetic Trip Unit CURRENT IN PERCENT OF BREAKER TRIP UNIT RATING (I n ) MINUTE HOUR HOURS,000,000,000 60 70 80 90 Minimum 0 Maximum Single Pole Trip Times at C Maximum 0 0 0 0 0 0 0 0,000 Circuit Breaker Time/Current Curves Series C L-Frame Circuit Breakers Equipped With Type LT Thermal-Magnetic Trip Unit Catalog Types LDB, LD, HLD Circuit Breakers,, and 4 Poles For application and coordination purposes only. Thermal calibration based on 40 C ambient, cold start. Connected with four (4) feet of rated wire (7 C) per terminal. Tested in open air with current in all poles. Instantaneous calibration based on single-pole tests. Maximum Voltage V., Ac (/60 Hz.) V., Dc Breaker Rated Amperes (I n ) Instantaneous Trip Amperes (See Figure Below),,,, Interrupting Breaker UL/CSA Type RMS Sym. ka, /60 Hz. LDB LD HLD LDB LD HLD,000,000 40,000,000 60,000 40 V. 480 V. V. V. IEC 947- RMS Sym. ka, /60 Hz. ka, Dc 40 V., (U e ) 80 V., (U e ) 4 V., (U e ) V., (U e ) Utilization Category A U IMP = 8 kv 70,000 80,000 90,000,000 to 0% of trip unit rating (Dc values are approximately 40% higher) ka, Dc I cu I cs I cu I cs I cu I cs I cu I cs 7 40 40 7 40 40 7 7,000,000,000 HOURS HOUR MINUTE Note: For additional information on the trip unit, see IL 9C606. ➀ Single pole data at C based on NEMA Procedures (AB 4-99) for verifying performance of molded case circuit breakers. Typical Trip Unit Nameplate 7 Magnetic Multiples Of I n C Thermal Magnetic Trip Unit 7 Amps (In) Push to Trip Cat. 40 C No. 7 Individual Pole Adjustments ±% ±% X X Adjustable Magnetic Trip.. Maximum Interrupting Time Interrupting Determines End of Curve.00.00 60 70 80 90 0 0 0 0 0 0 0 0 0,000,000,000 40,000,000 CURRENT IN PERCENT OF BREAKER TRIP UNIT RATING (I n ) 60,000 70,000 80,000 90,000,000 Curve No. SC-447-89B October 997
Cutler-Hammer Types FD and HFD Amperes Technical Data Effective: May 999 Page Page 6a MINUTE HOUR HOURS,000,000,000 7-A ➀ Maximum Single Pole Trip Times at C ➁ CURRENT IN MULTIPLES OF I n 4 6 7 8 9 40 60 708090 Circuit Breaker Time/Current Curves Molded-Case Circuit Breakers Catalog Types FD/HFD Circuit Breakers, Two, Three and Four Poles For application and coordination purposes only. Based on 40 C ambient, cold start. Connected with four (4) feet of rated wire (7 C) per terminal. Tested in open air with current in all poles. Maximum AC Volts: 690 at /60 Hz Maximum DC Volts: Breaker In Amperes Instantaneous Pick-up, Amperes RMS 7 Breaker Type FD HFD Interrupting s Symmetrical RMS Amperes (ka), Icu 40 Vac 480 Vac Vac 0 8 Vac Notes: ➀ Inverse Time Overcurrent Release. ➁ Single Pole Test Data at C based on NEMA Procedures (AB 4-99) for verifying performances of Molded Case Circuit Breakers. ➂ Total Operation Time. ➃ Interrupting Determines End of Curve. In this interruption region: The curve is drawn for I n = A. For I n A, the end points in this region are displaced along the current-axis by a factor (A/I n ),000,000 HOURS HOUR MINUTE Maximum Trip Time Minimum Trip Time 7 A A. A. ➂ ➃.00 4 6 7 8 9 40 60 708090 CURRENT IN MULTIPLES OF I n 0.00 Curve No. SC-6970-98A AD 9-67F
9-67F Page 6 Types FDB, FD and HFD Amperes 6 7 8 9,000 MINUTE HOUR HOURS,000,000 40 60 70 8090 A 0 Maximum Single Pole Trip Times at C 0 0 0 0 0 0 0 0 00 Circuit Breaker Time/Current Curves Series C F-Frame Circuit Breakers Catalog Types EHD, FDB, FD and HFD Circuit Breakers, Two, Three and Four Poles For application and coordination purposes only. Based on 40 C ambient, cold start. Connected with four (4) feet of rated wire (60 C up to amps, 7 C above amps) per terminal. Tested in open air with current in all poles. Maximum AC Volts: at 60 Hz Maximum DC Volts: Breaker Continuous Amperes Instantaneous Trip Amperes Amps See Curve Interrupting (UL/CSA Listed) Breaker Symmetrical RMS Amperes (KA) Amps (KA) Type @ 40 V., Ac @ 480 V., Ac @ V., Ac V., Dc FDB FD HFD 8 4 4 8 Single pole test data at C based on NEMA Procedures (AB 4-99) for verifying performance of molded case circuit breakers.,000,000 HOURS HOUR MINUTE Minimum Maximum.. Maximum Interrupting Time Interrupting Determines End of Curve (See Above).00 6 7 8 9 40 60 70 8090 0 0 0 0 0 0 0 0 0 00.00 Curve No. SC-449-87B October 997
9-67F Page Types EHD, FDB, FD and HFD Amperes 6 7 8 9,000 MINUTE HOUR HOURS,000,000 A 40 60 70 8090 0 Maximum Single Pole Trip Times at C 0 0 0 0 0 0 0 0 00 Circuit Breaker Time/Current Curves Series C F-Frame Circuit Breakers Catalog Types EHD, FDB, FD and HFD Circuit Breakers, Two, Three and Four Poles For application and coordination purposes only. Based on 40 C ambient, cold start. Connected with four (4) feet of rated wire (60 C up to amps, 7 C above amps) per terminal. Tested in open air with current in all poles. Maximum AC Volts: at 60 Hz Maximum DC Volts: Breaker Continuous Amperes Instantaneous Trip Amperes Amps See Curve Interrupting (UL/CSA Listed) Breaker Symmetrical RMS Amperes (KA) Amps (KA) Type @ 40 V., Ac @ 480 V., Ac @ V., Ac V., Dc EHD FDB FD HFD 8 8 4 4 -- 4 8 Single pole test data at C based on NEMA Procedures (AB 4-99) for verifying performance of molded case circuit breakers.,000,000 HOURS HOUR MINUTE Minimum Maximum.. Maximum Interrupting Time Interrupting Determines End of Curve (See Above).00 6 7 8 9 40 60 70 8090 0 0 0 0 0 0 0 0 0 00.00 Curve No. SC-446-87B October 997
9-67F Page 8 Types EHD, FDB, FD and HFD 60 Amperes 6 7 8 9,000 MINUTE HOUR HOURS,000,000 60A 40 60 70 8090 0 Maximum Single Pole Trip Times at C 0 Interrupting (UL/CSA Listed) Breaker Symmetrical RMS Amperes (KA) Amps (KA) Type @ 40 V., Ac @ 480 V., Ac @ V., Ac V., Dc EHD FDB FD HFD 0 0 8 8 0 0 0 0 0 00 Circuit Breaker Time/Current Curves Series C F-Frame Circuit Breakers Catalog Types EHD, FDB, FD and HFD Circuit Breakers, Two, Three and Four Poles For application and coordination purposes only. Based on 40 C ambient, cold start. Connected with four (4) feet of rated wire (60 C up to amps, 7 C above amps) per terminal. Tested in open air with current in all poles. Maximum AC Volts: at 60 Hz Maximum DC Volts: Breaker Continuous Amperes Instantaneous Trip Amperes 60 Amps See Curve 4 4 -- 4 8 Single pole test data at C based on NEMA Procedures (AB 4-99) for verifying performance of molded case circuit breakers.,000,000 HOURS HOUR MINUTE Minimum Maximum.. Maximum Interrupting Time Interrupting Determines End of Curve (See Above).00 6 7 8 9 40 60 70 8090 0 0 0 0 0 0 0 0 0 00.00 Curve No. SC-44-87B October 997
9-67F Page 7 Types EHD, FDB, FD and HFD Amperes 6 7 8 9,000 MINUTE HOUR HOURS,000,000 A 40 60 70 8090 0 Maximum Single Pole Trip Times at C 0 Interrupting (UL/CSA Listed) Breaker Symmetrical RMS Amperes (KA) Amps (KA) Type @ 40 V., Ac @ 480 V., Ac @ V., Ac V., Dc EHD FDB FD HFD 0 0 8 8 0 0 0 0 0 00 Circuit Breaker Time/Current Curves Series C F-Frame Circuit Breakers Catalog Types EHD, FDB, FD and HFD Circuit Breakers, Two, Three and Four Poles For application and coordination purposes only. Based on 40 C ambient, cold start. Connected with four (4) feet of rated wire (60 C up to amps, 7 C above amps) per terminal. Tested in open air with current in all poles. Maximum AC Volts: at 60 Hz Maximum DC Volts: Breaker Continuous Amperes Instantaneous Trip Amperes Amps See Curve 4 4 -- 4 8 Single pole test data at C based on NEMA Procedures (AB 4-99) for verifying performance of molded case circuit breakers.,000,000 HOURS HOUR MINUTE Minimum Maximum.. Maximum Interrupting Time Interrupting Determines End of Curve (See Above).00 6 7 8 9 40 60 70 8090 0 0 0 0 0 0 0 0 0 00.00 Curve No. SC-44-87B October 997