A. Provide a complete system of overcurrent protective devises as indicated on the drawings, and as specified herein.

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1 16475 OVERCURRENT PROTECTIVE DEVICES ************************************************************************************************************* SPECIFIER: CSI MasterFormat 2004 number: An optional keynote to the Drawings follows major product titles, for A/Es using National CAD Standard. ************************************************************************************************************* PART 1 GENERAL 1.1 SUMMARY A. Provide a complete system of overcurrent protective devises as indicated on the drawings, and as specified herein. 1.2 Related Sections: Switchboards Disconnect Switches Panelboards Motor Starters Motor Control Centers. 1.3 SYSTEM DESCRIPTION A. Performance Requirements: Materials shall be listed by an OSHA approved Nationally Recognized Testing Laboratory (NRTL). 1.4 SUBMITTALS A. Submit properly identified manufacturer's literature, product data, and technical data before starting work. 1.5 QUALITY ASSURANCE A. NEMA AB (National Electrical Manufacturers Association) Molded Case Circuit Breakers and Molded Case Switches. B. UL 489 (Underwriters Laboratories Inc.) Molded Case Circuit Breaker Enclosures. C. UL943 Standard for Ground Fault Circuit Interrupters. D. CSA C22.2 No. 5.1 M91 (Canadian Standard Association) Molded Case Circuit Breakers. E. Federal Specification W- C 375b/GEN Circuit Breakers, Molded Case; Branch Circuit and Services. F. National Fire Protection Association NFPA 70 (National Electric Code). G. Fuses shall comply with NEMA FUI and ANSI C Project Name M-DCPS MASTER Jan 04 Project No. SPECIFICATION GUIDELINES

2 PART 2 PRODUCTS 2.1 MANUFACTURERS A. Circuit Breakers: 1. GE. 2. Siemens. 3. Square D. B. Fuses: 1. Bussman Manufacturing. 2. Gould-Shawmut Company. 3. CEFCO. 4. Littelfuse, Inc. 2.2 EQUIPMENT A. Circuit Breakers: 1. Conform to Federal Specification W-C-375a and NEMA Standard AB-1, unless indicated otherwise. 2. Lugs and terminals: UL approved for copper-aluminum. 3. Accessories: 120 volt. 4. Each circuit breaker shall be provided with a trip unit for each pole with elements providing inverse time delay under overload conditions and instantaneous magnetic trip for short circuit protection, unless indicated as non-automatic. Trip elements shall operate a common trip bar to open all elements. 5. All circuit breakers shall be bolt-on type, consisting of the number of poles and ampere ratings as noted on the drawings. 6. Two and three pole breakers shall be of the common trip type. 7. Circuit breakers shall be a circuit interrupting device operating both manually for normal switching functions and automatically under overload and short circuit conditions, while providing circuit and self-protection when applied in its ratings. Provide at voltage, phase, and amps indicated, with symmetrical amperes interrupting rating to be equal or larger than that shown on drawings. Control and signaling function may be incorporated by use of accessories. 8. Operating mechanism shall be entirely trip-free so contacts cannot be held close against an abnormal over-current or short circuit condition. 9. Operating handle of circuit breaker shall open and close all poles of a multi-pole breaker simultaneously. Circuit breakers shall meet applicable NEMA AB-1 and have UL label. 10. Ampere rating shall be clearly visible. Contacts shall be of non-welding silver alloy. Circuit breakers to be used in switchboards, lighting and power panelboards, distribution panelboards and individually enclosed shall be 1, 2, or 3 poles as indicated on drawings. B. Molded Case Circuit Breakers Characteristics - General: Project Name M-DCPS MASTER Jan 04 Project No. SPECIFICATION GUIDELINES

3 1. Circuit Breakers shall be constructed using glass reinforced insulating material. Current carrying components shall be completely isolated from the handle and the accessory mounting area. 2. Circuit breakers shall have an over center, trip free, toggle operating mechanism which will provide quick make, quick break contact action. 3. The circuit breaker handle shall reside in a tripped position between on and off to provide local trip indication. Circuit breaker escutcheon shall be clearly marked on and off in addition to providing International I/O markings. 4. The maximum ampere as established by a NRTL, or other certification standards, with applicable voltage systems and corresponding interrupting ratings, shall be clearly marked on face of circuit breaker. 5. Circuit breakers shall be factory sealed with a hologram quality mark and shall have date code on face of circuit breaker. 6. Circuit breaker combinations for series connected interrupting ratings shall be listed by a NRTL as a recognized component combinations. Any series rated combination used shall be marked on the end use equipment along with the statement Caution Series Rated System A Available. Identical Replacement Component Required. 7. Circuit breakers shall be equipped with NRTL listed electrical accessories as noted on the electrical drawings. Circuit breaker handle accessories shall provide provisions for locking handle in the On and Off position. 8. Circuit breakers shall be NRTL listed for reverse connection without restrictive line and load markings and be suitable for mounting in any position. 9. Molded case circuit breakers shall be bolt-on type, mounted in lighting and power panelboards and individually enclosed units. 10. Molded case circuit breakers shall be quick-make, quick-break action. 11. Molded case circuit breakers for panelboards shall have a short circuit current rating based on the coordination and short circuit study or the following minimum symmetrical ampere interrupting capacities (RMS): a. 120 volts: 10,000 SAIC power panelboards (miminum). b. 277 volts: 14,000 SAIC lighting panelboards (minimum). c. 277/480 volts: Up to 50,000 SAIC distribution panelboards, or as shown on drawings. 12. Each molded case circuit breaker shall have a thermal magnetic trip device, with common tripping for all poles, and with trip ratings as shown on drawings. C. Electronic Trip Circuit Breakers With Standard Function Trip System 2000 amp maximum 1. Circuit breaker trip system shall be a micro compressor based true rms sensing design with sensing accuracy through the thirteenth (13 th ) harmonic. Sensor ampere ratings shall be as indicated on the associated electrical drawings. 2. The integral trip system shall be independent of any external power source and shall contain no less than industrial grade electronic components. 3. The ampere rating of the circuit breaker shall be determined by the combination of an interchangeable rating plug, the sensor size and the long time pickup adjustment on the circuit breaker. The sensor size, rating plug and the adjustment positions shall be clearly marked on the face of the circuit breaker. Circuit breakers shall be listed by a NRTL to carry 80% or 100% (if working as a service entrance main breaker) of their Project No. SPECIFICATION GUIDELINES

4 ampere rating continuously as specified or designed on the associated electrical drawings. 4. The following time/ current response adjustments shall be provided. Each adjustment shall have discrete settings and shall be independent of all other adjustments. a. Long Time Pickup Instantaneous Pickup b. Long Time Delay (Ground Fault Pickup) c. Short Time Pickup (Ground Fault Delay (I2t OUT only)) d. Short Time Delay e. Ground Fault Pickup {Service Entrance Main if required or designed.} f. Ground Fault Pickup {Service Entrance Main if required or designed.} 5. A means to seal the trip unit adjustments in accordance with NEC Section 240-6(b) shall be provided. 6. Local visual trip indication for overload, short circuit and ground fault trip occurrences shall be provided. 7. Long Time Pickup indication to signal when loading approaches or exceeds the adjusted ampere rating of the circuit breaker shall be provided. 8. Circuit breaker trip system shall be equipped with an externally accessible test port for use with a Universal Test Set. Disassembly of the circuit breaker shall not be required for testing. Test set shall be capable of verifying the operation of all trip functions with or without tripping the circuit breaker. D. Fuses: 1. Provide rejection fuses for fusible equipment regardless of which trade has furnished such equipment. 2. The time-current characteristic and ratings shall assure positive selective coordination. 3. All fuses: current limiting and have an interrupting capacity of at least 200,000 amperes RMS symmetrical. 4. The time-current characteristics and ratings shall be set in such a way that positive selective coordination is assured. 5. Coordination and current limitation for the protection of each part of the electrical system must be designed around the type and class and manufacturer selected for that type and class. 6. Fuses, 601 amperes and larger, shall comply with UL Class L standard and be Shawmut Form 480 "Amp-Trap" or Bussman "Hi Cap". 7. Fuses, 600 amperes and lower, where applied to general feeder and branch circuit protection, shall comply with UL Class RKl standards and be Shawmut dual element "Amp- Trap" or Bussman "Low Peak" Limitron. 8. Dual element fuses shall have low resistance and relatively low operating temperatures. Fuses shall be provided with thermal protection against damage from poor contact. Fuse shall open when temperature at thermal cutout reaches 280 degrees F., preventing damage to clips and switches before fuse opens. They shall combine high interrupting capacity (200,000 ampere RMS symmetrical) with time delay, holding 500 percent load for a minimum of 10 seconds. 9. Individual motor circuit fuses shall be sized at approximately 150 percent of motor full load current. Fuses, below 600 amperes shall comply with UL Class RK1, time delay, dual element standardsand be Gould-Shawmut "Amp-Trap" or Bussman Type LPN- Project No. SPECIFICATION GUIDELINES

5 RK. Fuses 601 amperes and larger, shall comply with UL Class L standards and be Gould-Shawmut Form 480 "Amp-Trap" or Bussman Type KRP-C. 10. Provide 10 percent spares (minimum of three) of each size and type of fuses furnished. Spare fuses shall be placed in a wall-mounted cabinet located in the main electric room. PART 3 EXECUTION 3.1 INSPECTION A. Do not proceed with the work of this section until conditions detrimental to the proper and timely completion of the work have been corrected in an acceptable manner. 3.2 INSTALLATION A. Install all circuit breakers and fuses where indicated on drawings, where required by NEC or other applicable codes and regulations, and in accordance to manufacturer's recommendations and accepted submittals. Special attention shall be given to air conditioning equipment. B. Two and three pole breakers must be true two and three pole breakers. 1. Do not combine single pole breakers with common handle connection to meet multiple pole breaker requirements. C. Label circuit breaker enclosures with 1 inch high stenciled letters showing equipment served. D. Circuit breaker pick-up level and time delay settings shall be adjusted to values indicated on the coordination study. END OF SECTION Project No. SPECIFICATION GUIDELINES