Specifications

6 YORK INTERNATIONAL
Section 2
MICROCOMPUTER CONTROL CENTER
NOTE: This instruction covers operation of chillers equipped with Electro-Mechanical or Solid State Starters. If
chiller is equipped with Variable Speed Drive, Form 160.00-O1 is to be used in conjunction with this
manual.
INTRODUCTION
FIG. 4 - MICROCOMPUTER CONTROL CENTER AND KEYPAD
• CHILLED LIQUID TEMPERATURES - LEAVING AND
RETURN
• REFRIGERANT PRESSURES - EVAPORATOR AND
CONDENSER
• DIFFERENTIAL OIL PRESSURE
• CONDENSER LIQUID TEMPERATURES - OPTIONAL
FIELD INSTALLED - LEAVING AND RETURN
• OPTIONS
• PRINT
• HISTORY PRINT
• MOTOR CURRENT IN % OF FULL LOAD AMPS
• SATURATION TEMPERATURES - EVAPORATOR
AND CONDENSER
• DISCHARGE TEMPERATURE
• OIL TEMPERATURE
• PURGE PRESSURE
• SOLID STATE STARTER MOTOR CURRENT/ VOLTS
The YORK MicroComputer Control Center is a micro-
processor based control system for centrifugal chill-
ers. It controls the leaving chilled water temperature
via prerotation vane control and has the ability to
limit motor current via control of the prerotation
vanes. Further, it is compatible with YORK Solid
State Starter, Electro-Mechanical Starter and Vari-
able Speed Drive applications.
A keypad mounted on the front of the Control Center
(see Fig. 4) allows the operator to display system operat-
ing parameters on a 40 character alphanumeric display
that is part of the keypad. These readings are displayed
via “Display” keypad as follows: In the English mode;
temperatures in °F, pressures in (PSIA); in the metric
mode, temperatures in °C, pressures in (KPa).
28050A
LD00457