
FORM
1. INTRODUCTION & PHYSICAL DESCRIPTION
8
29023A
1.1 GENERAL
The YORK Screw Chiller Control Panel is a micropro- cessor based control system fitted to YCAS liquid chill- ers. It is capable of
User interface is via a touch keypad and a liquid crystal display allowing access to operating and programmed data. Information can be displayed in English (Imperial) units or SI (Metric) units (Section 8.1). Conversion tables are provided at the back of this manual.
A master ON/OFF rocker switch is provided on the chiller control panel to activate or deactivate the com- plete chiller, while switches to activate or deactivate individual refrigerant systems are provided on the Mi- croprocessor Board.
External interface is available for control of the chiller via a YORK ISN System or YORK Remote Control Center. In addition, EMS/BAS System connections are
provided for remote cycling, current limiting, remote temperature setpoint reset and alarm annunciation.
YCAS chillers each have a single split circuit evapo- rator serving 2 independent refrigerant systems. YCAS 2 system chillers are configured as a single self contained section with a single control panel controlling the two refrigerant systems.
1.2 KEYPAD & DISPLAY
An operator keypad allows complete control of the chiller from a central location. The keypad offers a multitude of commands available to access displays, program setpoints, and initiate system commands. Keys are grouped and color coded for clarity and ease of use.
A 40 Character Liquid Crystal Display (2 lines of 20 characters) is used for displaying system parameters and operator messages. The display has a lighted back- ground for night viewing as well as a special feature which intensifies the display for viewing in direct sunlight.
Displays will be updated every two seconds by the microprocessor.
YORK INTERNATIONAL | 123 |