liquid temperature cutout, low suction pressure cutout, high discharge pressure cutout,
6.Display Data: Return and leaving liquid tem- peratures, low leaving liquid temperature cut- out setting, low ambient temperature cutout set- ting, outdoor air temperature, English or metric data, suction pressure cutout setting, each system suction pressure,discharge pres- sure (standard on
7.System Safeties: Shall cause individual com pressor systems to perform auto shut down; manual reset required after the third trip in 90 minutes. Includes: high discharge pressure, low suction pressure, high pressure switch, and motor protector. Compressor motor protector shall protect against damage due to high input current or thermal overload of windings.
8.Unit Safeties: Shall be automatic reset and cause compressors to shut down if low ambi- ent, low leaving chilled liquid temperature, un- der voltage, and flow switch operation. Contrac- tor shall provide flow switch and wiring per chiller manufacturer requirements.
9.Alarm Contacts: Low ambient, low leaving chilled liquid temperature, low voltage, low battery, and (per compressor circuit): high dis- charge pressure, and low suction pressure.
D.Manufacturer shall provide any controls not listed above, necessary for automatic chiller operation. Mechanical Contractor shall provide field control wiring necessary to interface sensors to the chiller control system.
2.06POWER CONNECTION AND DISTRI- BUTION
A.Power Panels:
1.NEMA 3R/12 (IP55) rain/dust tight, powder painted steel cabinets with hinged, latched, and gasket sealed outer doors. Provide main power connection(s), control power connections, com- pressor and fan motor start contactors, current overloads, and factory wiring.
2.Power supply shall enter unit at a single loca- tion, be 3 phase of scheduled voltage, and connect to individual terminal blocks per com- pressor. Separate disconnecting means and/ or external branch circuit protection (by Con- tractor) required per applicable local or national codes.
B.Exposed compressor, control and fan motor power wiring shall be routed through liquid tight conduit.
2.07ACCESSORIES AND OPTIONS
Some accessories and options supercede standard product features. Your YORK representative will be pleased to provide assistance.
A.Microprocessor controlled, Factory installed Across-
B.Outdoor Ambient Temperature Control
1.Low Ambient Control: Permits unit operation to 0°F ambient. .
2.High Ambient Control: Permits unit operation above 115°F ambient.
C.Power Supply Connections:
1.Single Point Power Supply: Single point Termi- nal Block for field connection and interconnect- ing wiring to the compressors. Separate exter- nal protection must be supplied, by others, in the incoming power wiring, which must comply with the National Electric Code and/or local codes. Standard unit controls to 25°F ambient. Low Ambient Control standard on
2.Single Point Power Supply with individual Sys- tem Breakers: Single or Terminal Block(s) for field connection and factory interconnecting wiring to factory supplied system breakers . Available on
3.Single Point or Disconnect: Single or Dual point
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