York 00497VIP manual System Architecture, Service, Refer To Fig

Service

SYSTEM ARCHITECTURE

(REFER TO FIG. 28)

The OptiView Remote Control Center (RCC) performs the following functions:

•Displays chiller operating conditions, alarms, shutdown messages and history data.

•Accepts operator-programmed setpoints.

•Provides chiller operating data and status to remote devices via serial communications.

•Allows real-time data and history data to be printed on an optional printer.

The RCC is a microprocessor based control system that receives analog and serial data inputs and controls serial data outputs per instructions in the operating program. A panel mounted display and touch-sensitive keypad permit remote operation.

In some applications, overall system temperatures are sensed by thermistors connected to the Remote Control Center. The output of each thermistor is a DC voltage that is analogous to the temperature it is sensing. Typical output voltage range of both is 0.5 to 4.5VDC. These are analog inputs to the Remote Control Center.

Serial Data is transmitted to and received from devices in RS-232, RS-485 and TX/RX (opto-couple) form.

All OptiView Remote Control Centers contain the following standard components:

•Microboard

•Keypad

•Display

•Power Supply

Figure 33 is a Remote Control Center block diagram of the standard components.

The microprocessor and all supporting logic circuits, along with the memory devices containing the operating program, reside on the Microboard. All remote control decisions are made here. In some applications it receives analog inputs from devices. The analog inputs are connected directly to the Microboard.

A front panel-mounted Keypad allows Operator and Service Technician user interface. Membrane keys are used to display chiller and system parameters, enter setpoints and perform chiller and Remote Control Center diagnostics.

A front panel mounted liquid crystal Display allows graphic animated display of the connected chiller units, chiller unit subsystems and system parameters. The chiller and working components of the chiller are displayed, along with chiller operating pressures and temperatures. The Keypad is used to select displays showing increasing levels of detail of chiller working components.

A self-contained Power Supply supplies the necessary DC voltages for all the components within the Remote Control Center.

Serial data interface to the YORK ISN Building Automation System is through the J12 connector.

66 YORK INTERNATIONAL