power distribution - Siemens

13SWITCHGEARMedium Voltage Equipment38 kV GM38 Metal-Clad Switchgear General/SpecificationsDrawout Indoor Switchgear▪ Horizontal drawout type 38-3AHvacuum circuit breaker▪ Uses the latest developments invacuum interrupter technologyRatingsTable 8Measured ParameterGeneral Nominal Voltage ClassRatedValuesTable 9Type 38-3AH Circuit Breaker Ratings▪ Highly reliable vacuum interrupters –MTTF over 42,500 years▪ Up to 50 full-fault interruptions▪ Meets or exceeds the latest ANSI,IEEE and NEMA standards▪ Universal spare circuit breaker▪ Interlock permits insertion of higherrating vacuum circuit breaker intolower rated cell but not vice-versa▪ Front accessible circuit breakeroperating mechanism for ease ofmaintenance▪ Closed door racking▪ Floor rollout circuit breaker in lowercell without a dollyCircuit Breaker Type38-3AH- 38-3AH-1500 31 RelatedRequiredCapabilities38-3AH-40 kV 38.0 38.0 38.0Nominal 3-PhaseRatedVoltageInsulationLevelsMVA Class MaxVoltage Range FactorRated WithstandTest VoltageLow FrequencyImpulseMVAE kV RMSKkV RMSkV Crest150038.01.65801501200—38.01.0801501200—38.01.0801501200Continuous Amperes 2000 2000 20003000FC 3000FC 3000FCRatedCurrent Short circuit (at rated max. kV) I kA RMS 21 31.5 40Interrupting TimeCycles 5 5 5Permissible Tripping Delay YSec.2 2 2Rated Max. Voltage Divided by KE/K kV RMS 23 38 38CurrentMax. Sym. Interrupting K Times Rated kA RMS 35 31.5 403-Sec. Short Time Short CircuitCurrent Carrying Current KI kA RMS 35 31.5 40Closing andkA RMS 56 50 62Latching(Momentary) kA Crest 95 85 104 Type 38-3AH-1500 ratings are in accord with ANSI C37.06-1987. Type 38-3AH-31 and 38-3AH-40 ratings conform toC37.06-2000 ratings. Maximum voltage for which the circuit breaker is designed and the upper limit for operation. K is the ratio of rated maximum voltage to the lower limit of the range of operating voltage in which the requiredsymmetrical and asymmetrical interrupting capabilities vary in inverse proportion to the operating voltage. 3000 ampere ratings are achieved using forced air cooling in the switchgear cubicle. To obtain the required symmetrical interrupting capability of a circuit breaker at an operating voltage between 1/K timesrated maximum voltage and rated maximum voltage, the following formula shall be used.Rated Maximum VoltageRequired Symmetrical Interrupting Capacity = Rated Short Circuit Current ×Operating VoltageFor operating voltages below 1/K times rated maximum voltage, the required symmetrical interrupting capability of thecircuit breaker shall be equal to K times rated short circuit current. With the limitations stated in 5.10 of ANSI Standard C37.04-1979, all values apply for polyphase and line-to-line faults.For single phase-to-ground faults, the specific conditions stated in 5.10.2.3 of ANSI Standard C37.04-1979 apply. Current values in this row are not to be exceeded even for voltages below 1/K times rated maximum voltage.For voltages between rated maximum voltage and 1/K times rated maximum voltage, follow 5 above. Current values in this row are independent of operating voltage up to and including rated maximum voltage. Included for reference only—not listed in ANSI C37.06.Type 38-3AH Circuit Breaker Control DataControl Voltages, ANSI C37.06 Table 10 Coil Amperes Spring Charging MotorRangeAmperesNominal Close Trip Close Trip Run (Avg.) Inrush (Peak)ChargingSeconds48 VDC 38–56 28–56 2.1 20 8 2510125 VDC 100–140 70–140 1.0 5.4 4 1810250 VDC 200–280 140–280 0.5 2.1 2 1010120 VAC 104–127 — 0.9 — 6 —10240 VAC 208–254 — 0.4 — 3 —10 Current at nominal voltage.▪ Visible secondary disconnect▪ One high construction▪ Pair with Siemens relays to match anyapplicationTable 10 Interrupting CapacityAuxiliary Switch ContactsTypeSwitchCont.CurrentAmperesNon-inductiveBreaker 10TOC15MOC 20InductiveBreakerTOCMOCTable 11Table 12Volt.Class38kV1 Bushing38kV2 Bushing101520RatioCircuit InterruptingCapacity in AmperesControl Circuit Voltage120AC 240AC 48DC 125DC 250DC10 5 10 9.6 4.815 10 0.5 0.5 0.215 10 10 10 56 3 10 6 315 10 0.5 0.5 0.215 10 10 10 5Current Transformers 60 Hz Metering Accuracyat BurdenRatio B0.1 B0.5 B1.0 B2.0Type MD38 Torroidal Standard Accuracy100:5150:5200:5250:5300:5400:5500:5 600:5800:51000:5 1200:51500:5 2000:52500:5 3000:52.40.60.60.60.60.30.30.30.30.30.30.30.30.30.3—2.41.21.21.20.60.30.30.30.30.30.30.30.30.3Type MDD38 High Accuracy 2.475:.5100:5150:5200:5250:5300:5400:5500:5600:5800:51000:5 1200:51500:52000:52500:53000:52.41.20.60.60.30.30.30.30.30.30.30.30.30.30.34.84.82.41.21.20.60.60.30.30.30.30.30.30.30.30.3Voltage TransformersAccuracyClassat 120VW,X,Y,Z ZZVAThermalRating(55°CAmb)20125:115 0.3 1.2 100024000:12027600:11534500:115———2.41.21.20.60.60.60.30.30.30.30.30.3——4.82.41.21.20.60.60.60.30.30.30.30.30.30.3————2.41.21.21.20.60.30.30.30.30.30.3——4.84.82.42.41.20.60.60.30.30.30.30.30.30.3RelayClassC 10C 20C 25C 35C 40C 60C 75C100C130C170C200C180C210C300C300C 15C 20C 35C 50C 70C 90C120C150C200C250C300C400C440C450C550C700 1-second through-current and momentary current areequal to the ratings of the associated circuit breakers. Exceeds ANSI C37.20.2 Accuracy Limit. Multi-ratio current transformers available. The accuracyratings shown apply only to the full secondary winding.0.3 1.2 100013-12Siemens Power Distribution & Control, SPEEDFAX 2007-2008 Product Catalog