Model YCAV Air-Cooled Screw Compressor Liquid Chillers Style A

FORM 201.21-EG1 (711)B. Air-cooled Condenser:1. Coils: Internally enhanced, seamless coppertubes, mechanically expanded into aluminumalloy fins with full height collars. Subcooling coilan integral part of condenser. Design workingpressure shall be 450 psig (31 barg).2. Low Sound Fans: Shall be dynamically and staticallybalanced, direct drive, corrosion resistantglass fiber reinforced composite blades moldedinto low noise, full airfoil cross section, providingvertical air discharge from extended orifices.Guards of heavy gauge, PVC (polyvinyl chloride)coated or galvanized steel.3. Fan Motors: High efficiency, direct drive, 3-phase,insulation class “F”, current protected, TotallyEnclosed Air Over (TEAO), with double sealed,permanently lubricated ball bearings.2.05 POWER AND ELECTRICAL REQUIREMENTSA. Power/Control Panel:1. NEMA 3R (IP55), powder painted steel cabinetswith hinged, latched, and gasket sealedouter doors equipped with wind struts for saferservicing. Provide main power connection(s),compressor starters and fan motor contactors,current overloads, and factory wiring.2. Panel shall include control display accessdoor.B. Single Point Power (As standard for 2 and 3 compressor,available option for 4 compressor)1. Provide single point power connection to chiller,shall be 3 phase of scheduled voltage.2. Circuit breaker shall be provided at point ofincoming single point connection to providedisconnecting means AND be sized to providethe motor branch circuit protection, short circuitprotection and ground fault protection for themotor branch-circuit conductors, the motor controlapparatus and the motors. Circuit breakershall be equipped with lockable operating handlethat shall extend through power panel door sothat power may be disconnected without openingany panel doors.JOHNSON CONTROLSAnd/ORB. Multi Point Power (Standard for 4-compressor Units)1. Provide multi point power connections to chiller,shall be 3 phase of scheduled voltage (for 4-compressor units).2. Circuit breakers shall be provided at each pointof field power connection. Circuit breakers shallbe equipped with lockable handles. The circuitbreakers shall be sized to provide the motorbranch circuit protection, short circuit protectionand ground fault protection for the motor branchcircuitconductors, the motor control apparatusand the motors. The circuit breaker rating shallbe in accordance with UL508C. Factory wiringshall be provided from multiple circuit breakersto the system components. Refer to schedulefor size and number of power connections. Allpower connections shall be located in one areaof the chiller. If equipment supplied requirespower connections in more than one area of thechiller; mechanical contractor is responsible forcost and coordination of any changes to electricalor structural designs.C. Control Transformer: Power panel shall be suppliedwith a factory mounted and wired control transformerthat will supply all unit control voltage from the mainunit power supply. Transformer shall utilize scheduledline voltage on the primary side and provide 115V/1Øon secondary.D. Short Circuit Withstand Rating of the chiller electricalenclosure shall be (200V & 230V: 100,000 Amps, 380& 460V: 65,000 Amps, 575V: 42,000 Amps). Ratingshall be in accordance with UL508.E. Motor Starters: Motors starters shall be reduced inrushtype (Wye-Delta or Solid State) for minimum electricalinrush. Across the line type starters will not be acceptable.F. Power Factor:1. Provide equipment with power factor correctioncapacitors as required to maintain a displacementpower factor of 95% at all load conditions.2. The installing contractor is responsible for additionalcost to furnish and install power factorcorrection capacitors if they are not factorymounted and wired.G. Exposed compressor and fan motor power wiring shallbe routed through liquid tight conduit.2.06 CONTROLSA. General:1. Provide automatic control of chiller operation includingcompressor start/stop and load/unload,anti-recycle timers, condenser fans, evaporatorpump, evaporator heater, unit alarm contactsand run signal contacts.171