Full Gauge Controls RCK-602 Plus Manual Download Page 16

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14.SUCTION CONTROLS

14. 1

Suction control:

The suction control parameters are set in the following Menu:

Main Menu

1.Function Settings

2.Suction

c c

Parameterization of compressors:

Compressor control is associated with a suction pressostat

RCK-602

plus

allows controlling up to three suction pressostat with different

compressor configurations. Each suction pressostat can have up to six associated compressors.
The digital outputs indicated as O1, O2..., O6 are responsible for the ON | OFF control of compressors or unloader valves, while the analog outputs (0-
10 V), indicated as A1 and A2, send a signal for proportional control of frequency inverters.

RCK-602

plus

controls up to three unloader valves per compressor.

Note

Alarms on discharge pressostat may also affect suction compressors.

14.2 Compressor modulation:

Each compressor manufacturer has its own way to control the capacity of the compressors. The most common compressors have two
stages of operation: on or off. The ON | OFF modulation is used in this case. When compressors have their capacity regulated by means of
unloader valves or frequency inverters, the type is selected according to the options below:

ON | OFF (0 | 100) - ON-OFF modulation.
0 | 50 | 100 - One main output and one auxiliary output are associated for three-stage compressor control.
0 | 33 | 66 | 100 - One main output and two auxiliary outputs are associated for four-stage compressor control.
0 I 50 I 75 I 100 - One main output and two auxiliary outputs are associated for four-stage compressor control.
0 I 25 I 50 I 75 I 100 - One main output and three auxiliary outputs are associated for five-stage compressor control.
Inverter - Proportional modulation associated with an analog output.

For variable capacity compressors, which use unloader valves for their modulation, an activation mode (

1.2.1.30

- (

)) is assigned to the

sequence of control outputs according to the construction of the compressor. One digital output to drive the compressor motor (main output) and
auxiliary outputs to drive unloader valves. The main control output is the first to be on and the last to be switched off. On the other hand, the auxiliary
output is generally used to activate or deactivate an unloader valve to regulate the capacity of the compressor.

RCK-602

plus

has three activation

modes as shown in the table below:

Example:

For a compressor with two unloader valves where each valve removes 33.3% of compressor capacity, the modulation 0 | 33 | 66 | 100 can be

selected (parameter

1.2.x.22

- (

)). One output is defined for the compressor motor and associated with the main output (

1.2.x.35

), and

two auxiliary outputs for unloader valves (

1.2.x.36

and

1.2.x.37

). The behavior of the auxiliary outputs is defined by the parameter

“Compressor activation mode” (

1.2.x.28

- (

)).

In “incremental mode” when only the main compressor output is activated, the controller assumes that the compressor operates at 33.3% of its capacity.
Activating output 1 will increase the capacity to 66.6% and activating the auxiliary output 2 will increase the capacity to 100% of the variable compressor
capacity.

In “unloader mode” when the compressor output is activated, the controller assumes that the compressor operates at 100% of its capacity. When
auxiliary output 1 is activated, the capacity will be 66.6% and when the second auxiliary output is activated, the capacity will be 33.3%.

Incremental mode

Modulation 0 I 33 I 66 I 100

Modulation 0 I 50 I 75 I 100

Modulation 0 I 25 I 50 I 75 I 100

Modulation 0 I 33 I 66 I 100

Modulation 0 I 50 I 75 I 100

Modulation 0 I 33 I 66 I 100

Modulation 0 I 50 I 75 I 100

Modulation 0 I 50 I 100

Capacity