York R134A manual Power and Electrical Requirements, Controls

FORM 201.23-EG1 (1007)

with full height collars. Subcooling coil an integral part of condenser. Design working pressure shall be 450 PSIG (31 bar).

2.Low Sound Fans: Shall be dynamically and statically balanced, direct drive, corrosion re- sistant glass fiber reinforced composite blades molded into low noise, full airfoil cross section, providing vertical air discharge from extended orifices. Guards of heavy gauge, PVC (polyvi- nyl chloride) coated or galvanized steel.

3.Fan Motors: High efficiency, direct drive, 3- phase, insulation class “F”, current protected, Totally Enclosed Air Over (TEAO), with double sealed, permanently lubricated ball bear- ings.

2.05POWER AND ELECTRICAL REQUIREMENTS

A. Power/Control Panel:

1.NEMA 3R (IP55), powder painted steel cabi- nets with hinged, latched, and gasket sealed outer doors equipped with wind struts for safer servicing. Provide main power connection(s), compressor starters and fan motor contactors, current overloads, and factory wiring.

2.Panel shall include control display access door.

B. Single Point Power (As standard for 2 and 3 com- pressor chillers)

1.Provide single point power connection to chill- er, shall be 3 phase of scheduled voltage.

2.Terminal Block connections shall be provided at the point of incoming single point connec- tion.

C.Control Transformer: Power panel shall be supplied with a factory mounted and wired control transformer that will supply all unit control voltage from the main unit power supply. Transformer shall utilize sched- uled line voltage on the primary side and provide 115V/1Ø on secondary.

D.Short Circuit Withstand Rating of the chiller electrical enclosure shall be (380, 400, & 460V: 65,000 Amps).

Rating shall be IAW UL508.

E.Motor Starters: Motors starters shall be reduced inrush type (Wye-Delta or Solid State) for minimum electrical inrush. Across the line type starters will not be acceptable.

F.Power Factor:

1.Provide equipment with power factor correc-

JOHNSON CONTROLS

tion capacitors as required to maintain a power factor of 95% at all load conditions.

2.The installing contractor is responsible for ad- ditional cost to furnish and install power factor correction capacitors if they are not factory mounted and wired.

G.Exposed compressor and fan motor power wiring shall be routed through liquid tight conduit.

2.06CONTROLS

A. General:

1.Provide automatic control of chiller operation including compressor start/stop and load/un- load, anti-recycle timers, condenser fans, evaporator pump, evaporator heater, unit alarm contacts and run signal contacts.

2.Chiller shall automatically reset to normal chiller operation after power failure.

3.Unit operating software shall be stored in non-volatile memory. Field programmed set points shall be retained in lithium battery backed regulated time clock (RTC) memory for minimum 5 years.

4.Alarm contacts shall be provided to remote alert for any unit or system safety fault.

B.Display and Keypad:

1.Provide minimum 80 character liquid crystal display that is both viewable in direct sunlight and has LED backlighting for nighttime view- ing. Provide one keypad and display panel per chiller.

2.Display and keypad shall be accessible through display access door without opening main control/electrical cabinet doors.

3.Display shall provide a minimum of unit setpoints, status, electrical data, temperature data, pressures, safety lockouts and diagnos- tics without the use of a coded display.

4.Descriptions in English (or available language options), numeric data in English (or Metric) units.

5.Sealed keypad shall include unit On/Off switch.

C.Programmable Setpoints (within Manufacturer limits): display language; leaving chilled liquid temperature: setpoint, control range; local or remote control; units of measure; compressor lead/lag; and maximum chilled water setpoint reset temperature range.

D.Display Data: Chiller liquid return and leaving temper-

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