3.2.3 - The user interface
The user interface is in two parts:
•The main interface: This gives access to all of the control parameters for the unit. It consists of a
•The summary interface: This gives quick access to just the main control parameters for the unit. It comprises 12 buttons and 16 LEDs, and includes a schematic diagram of the unit.
3.2.4 - Connections between boards
The basic board and slave boards communicate with each other over an internal
Terminals 1, 2 and 3 on connector J9 (A, B, C are connected internally) of the basic board are connected to terminals 1, 2 and 3 of terminal J9 of the
Incorrect connection will render the system inoperative.
3.2.5 - Slave board addresses
Every slave board (except the
NOTE: Any incorrect address will prevent the unit from starting. Turn off the power before amending the address of any auxiliary board.
Board addresses
Board | Address switch |
|
|
|
| |||
| 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 |
|
|
|
|
|
|
|
|
|
0 | 0 | 0 | 1 | 1 | 1 | 0 | 1 | |
4xDO Fan board # 1 | 0 | 0 | 1 | 0 | 0 | 1 | 1 | 1 |
4xDO Fan board # 2 | 0 | 0 | 1 | 0 | 1 | 0 | 1 | 1 |
0 | 0 | 1 | 0 | 1 | 1 | 1 | 1 | |
0 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | |
RCPM # 1 (compressor A1) | 1 | 1 | 0 | 1 | 0 | 1 | 0 | 0 |
RCPM # 2 (compressor A2) | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 |
RCPM # 2 (compressor A3) | 1 | 1 | 0 | 1 | 1 | 0 | 0 | 1 |
RCPM # 2 (compressor A4) | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 |
RCPM # 3 (compressor B1) | 1 | 1 | 1 | 0 | 1 | 0 | 1 | 0 |
RCPM # 4 (compressor B2) | 1 | 1 | 1 | 1 | 0 | 1 | 0 | 1 |
RCPM # 4 (compressor B3) | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 |
RCPM # 4 (compressor B4) | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 |
3.2.6 - Power supply to the boards
All boards are supplied by a 24 V source, referred to earth. In the event of a power supply interrupt, the unit restarts automatically without the need for an external command. However, any faults active when the supply is interrupted are saved and may in certain cases prevent a circuit or unit from restarting.
NOTE: When connecting the power supply for the boards, maintain polarity.
3.2.7 - Light emitting diodes on boards
All boards continuously check and indicate the proper operation of their electronic circuits. A light emitting diode (LED) lights on each board when it is operating properly.
Red LED
•The MAIN red LED flashes at about 2 second intervals to show that the module is working properly.
•Irregular flashing or no flashing is a sign of a defective board.
Green LED
(item SIO on the board)
•This LED flashes continuously to show that the board is communicating correctly over its internal bus.
•If this LED is not flashing, check the wiring of the SIO bus and the address of the board (slave board only). If the basic board is not linked to any slave boards, this LED should not flash.
•If all slave boards indicate a communication fault, check the SIO bus connection on the basic board. If this connection is correct and the fault persists, replace the basic board.
Orange LED - CCN/clock board
•This LED flashes to show that the basic board is commu- nicating via the CCN bus.
3.3 - The controls
3.3.1 - Electronic expansion valve (EXV)
The EXV is used to adjust the refrigerant flow to changes in the operating conditions of the machine. For this purpose, a series of calibrated orifices are machined into the wall of the refrigerant inlet port. As the refrigerant passes through these orifices, it expands and becomes a
To adjust the refrigerant flow to changes in operating conditions, a piston moves constantly up or down to vary the
NOTE: The external connector of the EXV must be cleaned and coated with silicone grease (Part No. 397 EE) to keep out condensation and prevent corrosion.
3.3.2 - The head pressure controls
The controller can deal with the following:
•in the case of
•in the case of
7
