York MILLENNIUM 28971AR - Manual (Page 6)

YORK INTERNATIONAL 6
˜ Pulse width modulated (PWM) input for up to
40°F (22°C) total reset as standard.
˜
Optional Building Automation System interface
input card for up to 40°F (22°C) reset using a:
4 to 20 milliamp, 0 to 10 VDC input, or discrete
reset input. [NOTE: The Standard MicroPanel
can be directly connected to a YORK ISN Build-
ing Automation System via the standard on-
board RS485 communication port. This Option
also provides open system compatibility with
other communications networks (BACNET™ &
LONMARK™) via interface through standard
onboard 485 or 232 port and an external
YorkTalk Translator.]
♦
Additional functions (password protected) for pro-
gramming by a qualified service technician:
˜
Cut-outs for low and high ambient, low suction
pressure, high discharge pressure, high oil tem-
perature.
˜
Refrigerant type.
˜ High discharge pressure unload setpoint.
˜
Fan control discharge pressure set point.
˜
Fan ON/OFF pressure differential.
˜ Compressor motor current percent limit.
♦
The Standard unit controls permit operation down
to 0°F (-18°C) outdoor ambient temperature.
POWER PANEL
• Power panel housed in NEMA 3R/12 (IP55) rain/
dust tight, powder painted steel cabinets with hinged,
latched, and gasket sealed outer doors equipped
with wind struts for safer servicing. Two motor con-
trol center cabinets are provided, with independent
doors and separated by a steel barrier panel.
• Current transformers sense each phase, as an in-
put to the microprocessor, to protect compressor mo-
tors from damage due to: low input current, high in-
put current, unbalanced current, single phasing,
phase reversal, and compressor locked rotor.
• Control circuit transformer provides 115V / 1Ø power
to the unit control system. Includes factory primary
wiring from lockable disconnect on panel door sepa-
rate from the motor control centers, and secondary
wiring supply to the 24V, fused Microprocessor panel
transformer.
• Individual fan motor contactors & external overloads
per condenser fan motor.
• Exposed compressor and fan motor power wiring
routed through liquid tight conduit.
Specifications
(Continued )