60 Hz Distribution ESWS PDF

60 Hz Distribution ESWS FUNCTION OF THE DISTRIBUTION SYSTEM: The function of the 60 Hertz Power Distribution System is to reliably and continuously distribute 450 Volts AC and 60 Hz power, produced by the ship’s three SSGTGs or provided from the pier through ten shore power cables (12 receptacles a...

60 Hz Distribution ESWS FUNCTION OF THE DISTRIBUTION SYSTEM: The function of the 60 Hertz Power Distribution System is to reliably and continuously distribute 450 Volts AC and 60 Hz power, produced by the ship’s three SSGTGs or provided from the pier through ten shore power cables (12 receptacles are available), to all locations on the ship where required. Load Shedding: Another protective feature of the distribution system is the Load Shed function. The MFM will sense an overload condition (100% at 1 second) will then shunt trip all pre-determined non- vital loads first, followed by vital loads, if the over-current condition still exists. There are 2 stages of Load Shed: Stage 1– 100% of rated load for 100 milliseconds BREAKERS TRIPPED FOR STAGE ONE LOAD SHED Ventilation Preheaters Galley Equipment General Work Shop Laundry Non-Vital Engineering Equipment Stage 2– 100% of rated load for additional 5 seconds, after Stage 1 BREAKERS TRIPPED FOR STAGE TWO LOADSHED Air Condition Units VLS Anti-Icing heaters SPY-1D Anti-Icing heaters Load Shed can be initiated automatically by the COTS MFM or manually by watchstanders at the UCC or SWBDs. SHIPS SERVICE GAS TURBINE GENERATOR: The 3 GTGs consist of Rolls Royce 9140RF Generator sets, with 501-K34 Gas Turbine Engines used as the prime mover, Redundant Independent Mechanical Start System (RIMSS) and 3 Generators rated at 3,000 KW, 4,800 AMPS, 3 PHASE, 450 VOLTS, and 60Hz. NR 1 GTG is Located in AUX 1, NR 2 is located in MER 2, and NR 3 is in NR 3 GTG Room. SWITCHBOARDS The three Ship Service Switchboards (1S, 2S, AND 3S) have been designated to allow for zonal distribution of 60Hz, 450vac, 3 phase power. Each switchboard is further divided into three sections, SG (Generator control), SA (starboard distribution bus), and SB (port distribution bus) with Number 2 Switchboard (2S) having an additional section called 2SP (Shore Power). The SA and SG sections are located in the main spaces with their associated GTG. The SA sections house only their associated Cross Tie Breakers (XTBs). The 1SA section is integrated with LC 21 and is located in 4-126-0-E (AUX 1). The 2SA section is integrated with LC 41 and is located in 4-254-0-E (MER 2). The 3SA section is integrated with LC 51 and is located in 3-370-0-E (3 GTG Room). The SB sections are located outside the main spaces and house only their associated BTBs. a. The 1SB section is integrated with LC 22 and is located in 1-158-4-Q (NR 1 SWBD Room). b. The 2SB section is a stand-alone unit located in 1-254-2-Q (NR 2 SWBD Room). c. The 3SB section is integrated with LC 52 and is located in 01-338-2-Q (NR 3 SWBD Room). d. The SG sections contain all associated generator and generator breaker controls, the generator breakers and ground detectors used to detect phase to phase ground faults. SHORE POWER Shore power is supplied via twelve 400-amp receptacles located on the 01 level amidships. These receptacles feed the 2SP switchboard to provide power via 12 shore power circuit breakers (400 amp). When hooking up shore power, the ship will normally use 10 receptacles; this will provide the ship with 4000 amps. The remaining 2 receptacles are used for spares in case of failure of one of the 10. Shore power breakers can be opened and closed at the UCC and locally at the 2SP-switchboard located in MER 2. LOAD CENTERS Load Centers are extensions of the switchboards into other electrical zones throughout the ship. Each Load Center is installed to provide “Centralized Zonal Distribution” of selected zones. Load Centers have only one power source. If the SWBD that feed the load center is lost, then all the loads on the load center are lost as well. Power distribution zone and location identify load centers, with odd-numbered units on the starboard side and even-numbered units on the port side. a. There are six power distribution zones located on USS RALPH JOHNSON.  (1) Zone 1 (Frames 1-126) includes LC11, LC12, LC13 and LC14. (2) Zone 2 (Frames 126-220) includes 1SA/LC21, 1SB/LC22, LC23, LC24, LC25, LC26, LC27, LC28A and LC29. (3) Zone 3 (Frames 220-254) includes LC31 and LC32. (4) Zone 4 (Frames 254-300) includes 2SA/LC41, and LC42. (5) Zone 5 (Frames 300-and Aft) includes 3SA/1C51, 3SB/LC52, LC53 and LC54. (6) Zone 6 (All 01 Level and Above) includes LC61 and LC62. CASUALTY POWER Casualty Power Distribution System supplies temporary 60 Hz power to vital equipment and systems. The Casualty Distribution System consists of casualty power terminals and cable racks strategically located to allow temporary power cables to span damaged areas.  Table 1: Load Center Locations ZONE LOAD CENTER FRAME NUMBER NOMENCLATURE 1 LC 11, 13 2-53-1-C CSER 1 1 LC 12, 14 1-78-4-Q SHIPS OFFICE 2 1 SA/LC 21 4-126-0-E AUX 1 2 1 SB/LC 22, 28A 1-158-4-O SWBD RM No.1 2 LC 23, 25, 27, 29 4-126-0-E AUX 1 2 LC 24, 26, 1-174-01-L PASSAGE 3 LC 31 2-228-01-L STRS HANDLING 3 LC 32 1-220-2-L PASSAGE 4 2 SA/LC 41 4-254-0-E MER 2 4 LC 42 1-254-6-L PASSAGE 5 3 SA/LC 51 3-370-0-E 3 GEN 5 3 SB/LC 52 01-338-2-Q SWBD RM No.3 5 LC 53 3-370-0-E 3 GEN 5 LC 54 01-309-2-L PASSAGE 6 LC 61 01-158-1-L PASSAGE 6 LC 62 03-142-2-Q LD CTR RM NO.1 Figure 1: ZEDS Schematic Diagram