Fridgewatch 2100 Controller Mk4
Section 3
Publication 3-58
Issue 1.1 : 01/08
Page 87 of 152
11. Settings
Settings, configurable by the Supervisor Key holder or commissioning
engineer, enable the Fridgewatch 2100 Controller to provide suitable
control, regardless of the type of refrigeration plant to which it is applied.
There are two types of setting:
•
Operator settings:
can be modified by the operator while
the compressor is running and come into effect immediately.
•
Configuration settings:
affect the way Fridgewatch 2100
interfaces with the refrigeration plant and must be entered
before starting the plant for the first time.
Initially, the commissioning engineer will input suitable values. After the
commissioning period, these settings can only be modified by the
Supervisor Key holder. This person should be someone directly involved
with the operation and maintenance of the plant; refer to the notes on
using the Supervisor Key under 8.9. Supervisor Keyswitch.
11.1.
Operator Settings S1/S39
These settings will initially be determined by the commissioning engineer,
but as certain values may need to be altered later, they can be changed
from the Fridgewatch 2100 panel using the Supervisor Key and Settings
mode. Operator settings can be changed at any time, even while the
compressor is running. Care must be exercised though, as changing too
many parameters at the same time, or choosing unsuitable values, could
easily give rise to control instability.
Any changes to Operator Settings should be recorded in 16. Appendix 3 -
Settings Record.
Before making alterations to S5 Proportional Band, S6 Integral Action
Time or S7 Derivative Action Time, it is essential to have read and
understood the notes under 5. Principles of Control.
S1
Set point (units: pressure in bar g or temperature in °C)
This is the temperature or pressure value, depending on the chosen
control parameter, which Fridgewatch 2100 will attempt to control to
when ‘auto capacity control’ mode is selected.
The set point can be sensed from the same point on the plant as that
used for the start and stop measured variables, or from another point;
refer to the
NOTE
at the top of the next page.
S2
Start value (units: pressure in bar g or temperature in °C)
When operating in ‘auto start/stop’ mode, this is the value of temperature
or pressure which Fridgewatch 2100 uses to start the compressor. If
Fridgewatch 2100 controls two or three compressors, Fridgewatch
provides the start signal to the lead compressor according to the running
order selected using S4 Lead Compressor Number (Running Order).
The start measured variable can be sensed from the same point on the
plant as that used for the set point and stop measured variable, or from
another point; refer to the
NOTE
at the top of the next page.
S3
Stop value (units: pressure in bar g or temperature in °C)
When operating in ‘auto start/stop’ mode, this is the value of temperature
or pressure which Fridgewatch 2100 will use to stop the compressor.
The stop measured variable can be sensed from the same point on the
plant as that used for the set point and start measured variable, or from
another point; refer to the
NOTE
at the top of the next page.
