Fig 8 Possible Compressor Start/Stop And Capacity Control Modes - J&E Hall Fridgewatch 2100 Installation, Operating And Maintenance Manual

Fridgewatch 2100 Controller Mk4
List of Modes
1 Start/Stop
Mode
Selection
C M :
ONTROL ODE
S – S / C
TOP TART OMPRESSOR
C C
APACITY ONTROL
Off No control action.
Supervisor Key turned to the
Unlocked position,
Manual/Manual
pressed.
If a run enable signal has been
implemented (refer to Table 7),
Manual/Auto the run enable signal must be
available to permit starting.
Start measured variable
(pressure or temperature)
exceeds the start value, or early
start value S15 is implemented,
Fridgewatch 2100 detects the
measured variable's rate of
Auto/Auto
change exceeds that chosen.
If a run enable signal has been
implemented (refer to Table 7),
the run enable signal must be
available to permit starting.
Remote/Auto
Remote controller provides the
start signal (refrigeration
Remote/Remote
required).
1
Refer to 9.7. Changing the Operating Mode.
2
If S14 Run Enable Signal Required = 4, 5, 6 or 7 it is possible to use the remote load and unload digital inputs on
terminals 138/139 of the 3MIO1 input/output card to override the internal auto control algorithm; refer to the description of
S14 in 11.1. Operator Settings.

Fig 8 Possible Compressor Start/Stop and Capacity Control Modes

Section 3
Issue 1.1 : 01/08
Manual
Manual
S B C
TARTED Y OMPRESSOR
STOP COMPRESSORS
button
(ALL MODES) button pressed.
If a run enable signal has been
implemented (refer to Table 7),
removing the run enable signal
will stop the compressor.
STOP COMPRESSORS
(ALL MODES) button pressed.
or
Stop measured variable
(pressure or temperature) falls
below the stop value.
If a run enable signal has been
implemented (refer to Table 7),
removing the run enable signal
will stop the compressor.
STOP COMPRESSORS
(ALL MODES) button pressed.
or
Remote controller removes the
start signal (refrigeration no
longer required).
As it is important to equalise the number of hours each compressor runs,
the role of lead compressor should be changed from time to time.
Instead of having to remember to manually change the running order, the
operator can request Fridgewatch 2100 to do this automatically by setting
S4 = 0. When the plant has shutdown, all compressors stopped,
Fridgewatch 2100 assess how many hours each compressor has run and
assigns the role of lead to the compressor with the least number of hours
run; refer to the S4 description under 11.1. Operator Settings S1/S39.
Mode: (current mode)
Capacity Control
Manual
Auto
2
S B C
TOPPED Y
Supervisor Key turned to the
Unlocked position. Press the
button to load,
unload.
Fridgewatch 2100
Proportional, Integral and
Derivative (PID) algorithm.
Remote controller supplies
load and unload pulses.
C
APACITY ONTROL
button to
Publication 3-58
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