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8.1 - Unit start/stop control
The unit state is determined based on a number of factors,
including its operating type, active overrides, open
contacts, master/slave configuration, or alarms triggered
due to operating conditions.
The table given below summarizes the unit control type
[ctrl_typ] and its running status with regard to the
following parameters:
•
Operating type:
This operating type is selected using
the
Start/Stop
button on the user interface.
LOFF
Local off
L-C
Local on
L-SC
Local schedule
Rem
Remote
Net
Network
Mast
Master unit
•
Start/stop force command [CHIL_S_S]:
Chiller start/
stop force command can be used to control the chiller
state in the Network mode.
-
Command set to stop:
The unit is halted.
-
Command set to start:
The unit runs in
accordance with schedule 1.
•
Remote start/stop contact status [Onoff_sw]:
Start/
stop contact status can be used to control the chiller
state in the Remote operating type.
•
Master control type [ms_ctrl]:
When the unit is the
master unit in a two-chiller master/slave arrangement,
the master unit may be set to be controlled locally,
remotely or via network.
•
Start/stop schedule [chil_occ]:
Occupied or
unoccupied status of the unit.
•
Network emergency stop command [EMSTOP]:
If
activated, the unit shuts down regardless of the active
operating type.
•
General alarm:
The unit shuts down due to failure.
Active operating type
Parameter status
Result
LOFF
L-C
L-SC
Rem
Net
Mast
Start/stop
force
command
Remote
start/stop
contact
Master
control
type
Start/stop
time
schedule
Network
emergency
shutdown
General
alarm
Control
type
Unit
state
-
-
-
-
-
-
-
-
-
-
enable
-
-
off
-
-
-
-
-
-
-
-
-
-
-
yes
-
off
active
-
-
-
-
-
-
local
off
active
-
-
-
unoccupied
-
-
local
off
active
-
off
-
-
-
-
remote
off
active
-
-
-
unoccupied
-
-
remote
off
active
disable
-
-
-
-
-
network
off
active
-
-
-
unoccupied
-
-
network
off
active
-
-
local
unoccupied
-
-
local
off
active
-
off
remote
-
-
-
remote
off
active
-
-
remote
unoccupied
-
-
remote
off
active
disable
-
network
-
-
-
network
off
active
-
-
network
unoccupied
-
-
network
off
active
-
-
-
-
disable
no
local
on
active
-
-
-
occupied
disable
no
local
on
active
-
on_cool
-
occupied
disable
no
remote
on
active
-
on_heat
-
occupied
disable
no
remote
on
active
-
on_auto
-
occupied
disable
no
remote
on
active
enable
-
-
occupied
disable
no
network
on
active
-
-
local
occupied
disable
no
local
on
active
-
on_cool
remote
occupied
disable
no
remote
on
active
-
on_heat
remote
occupied
disable
no
remote
on
active
-
on_auto
remote
occupied
disable
no
remote
on
active
enable
-
network
occupied
disable
no
network
on
IMPORTANT: When the unit is stopping or there is a
demand to stop the unit, compressors are stopped
consecutively.
8 - STANDARD CONTROL OPERATIONS AND OPTIONS
In case of emergency stop, all compressors are stopped at
the same time.