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 2-digit primary display block and a secondary 4-digit display block with 10 LEDs and 5 buttons.

•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 three-wire RS485 communication bus (SIO bus). These three wires link all the boards in parallel.

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 NRCP-BASE board, terminal J4 of the PD4-EXV board respectively, except for terminal J3 of the 4xDO and 4xAI-2xAO boards where terminals 2 and 3 are reversed.

Incorrect connection will render the system inoperative.

3.2.5 - Slave board addresses

Every slave board (except the NRCP-BASE board) has a unique address controlled by 8 DIP switches. The switch is disabled when it is in the open position (OPEN or OFF). On RCPM boards SIO address switch is labelled 'ADDR'.

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

 

 

 

 

 

 

 

 

 

PD4-EXV

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

4xAI-2xAO board # 1

0

0

1

0

1

1

1

1

4xAI-2xAO board # 2

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 bi-phase mixture (liquid and gas).

To adjust the refrigerant flow to changes in operating conditions, a piston moves constantly up or down to vary the cross-section of the refrigerant path. This piston is driven by an electronically controlled linear stepper motor. The high degree of accuracy with which the piston is positioned ensures that the flow of refrigerant is precisely controlled.

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 air-cooled units, for each circuit, fan stages together with, if necessary, a variable speed fan (controlled by an optional 4xAI-2xAO board)

•in the case of water-cooled units, a water valve. This valve is controlled by an optional 4xAI-2xAO board which can deliver a 0-10 V d.c. or 4-20 mA signal, depending on the configuration.

7

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Carrier 30GK manual Board addresses, Red LED, Green LED, Orange LED CCN/clock board, Controls
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30GK specifications

The Carrier 30GK is a prominent chiller model known for its efficiency and reliability in various commercial and industrial applications. Offering a blend of advanced technology and robust design, the 30GK series caters to diverse cooling needs while maintaining energy efficiency and low operational costs.

One of the standout features of the 30GK is its use of the latest scroll compressor technology. This contributes to its efficient performance, enabling the chiller to operate at optimal levels while minimizing energy consumption. The scroll compressor is known for its quiet operation, which reduces noise pollution, making it an ideal choice for buildings located in noise-sensitive environments.

The 30GK chiller series is equipped with microchannel coil technology, which allows for improved heat exchange efficiency. The microchannel design uses a compact coil structure that enhances refrigerant flow and reduces refrigerant volume, leading to a smaller footprint compared to traditional coil designs. This innovative design not only saves space but also improves the chiller's overall performance.

Another notable characteristic of the Carrier 30GK is its environmental consciousness. The chiller operates using environmentally friendly refrigerants, aligning with modern regulations and sustainability goals. Its design incorporates energy-efficient components that contribute to significant reductions in greenhouse gas emissions, making it suitable for environmentally responsible projects.

Moreover, the 30GK is designed for easy serviceability, with accessible components that simplify maintenance. This feature is particularly important for facility managers seeking to minimize downtime and keep maintenance costs low. The chiller also includes advanced monitoring and control systems, which enable real-time performance tracking and diagnostics, enhancing operational efficiency.

In terms of performance, the 30GK chiller is known for its wide capacity range, making it versatile for various applications. Whether for commercial spaces, industrial processes, or large buildings, the 30GK can meet the cooling demands reliably.

Overall, the Carrier 30GK chiller represents a perfect balance of cutting-edge technology, energy efficiency, and sustainability. Its features make it a leading choice in the market, suited for those looking to invest in high-quality and dependable cooling solutions.
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