York R-407C manual Electrical Data, Electrical Service Sizing, Load Definitions, Compressors

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Electrical Data

ELECTRICAL SERVICE SIZING

In order to use the electrical service required for the cooling only Eco2 rooftop, use the appropriate calcula- tions listed below from U.L. 1995. Based on the operat- ing mode and configuration of the rooftop, the calcula- tions will yield different MCA (minimum circuit ampac- ity), and MOP (maximum overcurrent protection).

Using the following load definitions and calculations, determine the correct electrical sizing for your unit. All concurrent load conditions must be considered in the calculations, and you must use the highest value for any combination of loads.

Load Definitions:

•LOAD1 is the current of the largest motor – com- pressor or fan motor.

•LOAD2 is the sum of the remaining motor currents that may run concurrently with LOAD1 (i.e., exhaust fan motor).

TABLE 9 – COMPRESSORS

•LOAD3 is the current of the electric heaters – zero for cooling only units.

•LOAD4 is the sum of any remaining currents greater than or equal to 1.0 amp

Use the following calculations to determine MCA and MOP for units supplied with a single-point power connection:

MCA = (1.25 x LOAD1) + LOAD2 + LOAD4

MOP = (2.25 x LOAD1) + LOAD2 + LOAD4

If the MOP does not equal a standard current rating of an overcurrent protective device, then the marked maxi- mum rating is to be the next lower standard rating. How- ever, if the device selected for MOP is less than the MCA, then select the lowest standard maximum fuse size greater than or equal to the MCA.

	COMPRESSOR						NOMINAL VOLTAGE
	QUANTITY		208V			230V			460V				575V
	PER	MODEL	208V			230V			460V				575V
MODEL	PER	MODEL
MODEL	UNIT		RLA*		LRA*	RLA*		LRA*	RLA*		LRA*	RLA*		LRA*
	UNIT		RLA*		LRA*	RLA*		LRA*	RLA*		LRA*	RLA*		LRA*

50	4	SZ160	54.0		265.0	48.8		265.0	24.2		135.0	19.4		120.0

55	4	SZ160	54.0		265.0	48.8		265.0	24.2		135.0	19.4		120.0

60	4	SZ185	62.3		380.0	56.3		380.0	27.9		175.0	22.3		140.0

65	4	SZ185	62.3		380.0	56.3		380.0	27.9		175.0	22.3		140.0

* Values shown are per compressor

24	YORK INTERNATIONAL

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Contents Packaged Rooftop Air Conditioning Units 407C Optimized Through 65 TonsTable of Contents Nomenclature Basic Model NumberFEATURES/BENEFITS IntroductionEcological and Economical Design Serviceability Install with Ease and SafetyReliable Scroll Compressor Technology Introduction Physical Data Physical DataPhysical Data Cont’d Application Data LocationRigging EconomizerHarsh Environments Condenser and Evaporator Coil Protection Building Exhaust SystemsRoof Curb Selection Procedure Acoustical ConsiderationsGiven Select UnitCooling Performance Data 50 Ton Model Cooling Performance Data 50 TON ModelCooling Performance Data 50 TON Model CONT’D Cooling Performance Data 55 Ton Model Cooling Performance Data 55 TON ModelCooling Performance Data 55 TON Model CONT’D Cooling Performance Data 60 Ton Model Cooling Performance Data 60 TON ModelCooling Performance Data 60 TON Model CONT’D Cooling Performance Data 65 Ton Model Cooling Performance Data 65 TON ModelCooling Performance Data 65 TON Model CONT’D Fan Performance 50 Through 65 TON Supply FAN Data50 Through 65 TON Supply FAN Data CONT’D 50 Through 65 TON Exhaust FAN Data Component Static Pressure Drops Inches of Water Column Filters Economizer Economizer Dampers Rigid Filter Manual or Electrical Service Sizing Electrical DataLoad Definitions CompressorsSupply and Exhaust FAN Motor ODP or Tefc High EfficiencyPremium Efficiency Condenser FAN Motors / EachUnoccupied / Occupied Switching ControlsControl Sequences for ALL Units GeneralVentilation Control Sequences Exhaust Control SequencesLOW Ambient Operation Smoke Purge SequencesVAV Specific Sequences Cooling OperationStand Alone Control CV Specific SequencesCooling Operation Thermostat Control Stage 1 Y1 CallPower Wiring SINGLE-POINT Power Supply WiringSINGLE-POINT Power Supply Wiring With NON-FUSED Disconnect SINGLE-POINT Power Supply Wiring with NON-FUSED DisconnectDUAL-POINT Power Supply Wiring DUAL-POINT Power Supply WiringField Control Wiring Field Control WiringGeneral Arrangement DrawingBottom Supply Bottom Return Left or Right Rear Return Supply General Arrangement DrawingCurb Layout Drawing Curb Layout DrawingGuide Specifications ConstructionSupply AIR System Bearings and DrivesPower Supply AIR Filtering SystemAIR Inlet System Refrigeration SystemAccessories and Options ControlsEconomizers Relief System Evaporator Coil ProtectionCondenser Coil Protection Suction and Discharge Pressure Transducers moniYork International York International Proud Sponsor Olympic Team