Active operating type
Parameters' status
Control
type
Unit
state
LOFF
L-C
L-Sc Rem
Net
Mast
Start/
Stop force
command
Remote start/
stop contact
Master
control
type
Start/Stop
schedule
Network
Emergency
Shutdown
Alarm
shutdown
enable
off
yes
off
active
local
off
active
unoccupied
local
off
active
open
remote
off
active
unoccupied
remote
off
active
disable
network
off
active
unoccupied
network
off
active
local
unoccupied
local
off
active
open
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
closed
occupied
disable
no
remote
on
active
enable
occupied
disable
no
network
on
active
local
occupied
disable
no
local
on
active
closed
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. In case
of emergency stop, all compressors are stopped at the same time.
8 - STANDARD CONTROL OPERATIONS AND OPTIONS
8.1 - 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.
The table given below summarizes the unit control type [ctrl_typ]
and its running status with regard to the following parameters:
■
Operating type:
This operation 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]:
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 according to 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.
8.2 - Cooling / Heating
The table below summarises the unit operation based on the
following parameters:
■
Unit On/Off status: This parameter indicates whether the unit
is shut down (not authorised to start) or in operation (authorised
to start).
■
Control type: Indicates whether the unit operates in Local,
Remote or Network mode.
■
Heating/Cooling selection in Local mode: The operating mode
is selected via the user interface (GENUNIT menu).
■
Heat/Cool switch status in Remote mode: This contact is active
only when the unit is under remote control.
■
Heat/Cool selection in Network mode: The network command
[HC_SEL] permits heating/cooling control if the unit is in
Network operating mode.
Status Control
type
Heat/Cool
in Local
Heat/Cool
in Remote
Heat/Cool
in Network
Current unit
operating
mode
Off
-
-
-
-
-
On
local
cool
-
-
cooling
On
local
heat
-
-
heating
On
remote
-
on_cool
-
cooling
On
remote
-
on_heat
-
heating
On
network
-
-
cool
cooling
On
network
-
-
heat
heating
8.3 - Control interlock contact
This contact checks the status of a loop (customer safety loop).
It prevents the unit from starting if it is open when the delay at
start-up has expired. This open contact leads to an alarm shut-
down, if the unit is running (alarm 10014).
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