28
The table below summarises the unit control type and stop
or go status with regard to the following parameters.
• Operating type: this is selected using the start/stop
button on the front of the user interface.
• Remote start/stop contacts: these contacts are used
when the unit is in remote operating type (rEM). See
sections 3.6.2 and 3.6.3.
• CHIL_S_S: this network command relates to the chiller
start/stop when the unit is in CCN control (CCn).
Variable forced to disable: the unit is halted. Variable
forced to Enable: the unit runs in accordance with
schedule 1.
• Start/Stop schedule: occupied or unoccupied status of
the unit as determined by the chiller start/stop program
(Schedule #1).
• Master control type. This parameter is used when the
unit is the master unit in a two chiller lead/lag arrange-
ment. The master control type determines whether the
unit is to be controlled locally, remotely or through
CCN (this parameter is a Service configuration).
• CCN emergency shutdown: if this CCN command is
activated, it shuts the unit down whatever the active
operating type.
• General alarm: the unit is totally stopped due to failure.
5.2.1 - General
The heating/cooling/standby selection applies to all units.
But only 30RB (liquid chillers) units, controlling a boiler
can change over to heating mode. Heating/cooling control
can be automatic or manual.
In automatic mode the outdoor temperature determines
the heating/cooling/standby changeover based on the two
threshold values configured by the user (see Setpoint menu
for cooling and heating mode changeover thresholds). If the
unit is in standby it does not cool or heat, and no compressor
can be activated. The diagram below summarises the
operating principle in automatic mode.
Outdoor
temperature
Heating
threshold*
Cooling
threshold
* This threshold does not apply to cooling only units that do not control a boiler.
- - - - - - - - - - Enable - - O
- - - - - - - - - - - Yes - O
Active - - - - - - - - - - - Local O
- - Active - - - - - - Unoccupied - - Local O
- - - Active - - - O - - - - Remote O
- - - Active - - - - - Unoccupied - - Remote O
- - - - Active - Disable - - - - - CCN O
- - - - Active - - - - Unoccupied - - CCN O
- - - - - Active - - Local Unoccupied - - Local O
- - - - - Active - O Remote - - - Remote O
- - - - - Active - - Remote Unoccupied - - Remote O
- - - - - Active Disable - CCN - - - CCN O
- - - - - Active - - CCN Unoccupied - - CCN O
- Active - - - - - - - - Disable No Local On
- - Active - - - - - - Occupied Disable No Local On
- - - Active - - - On cooling - Occupied Disable No Remote On
- - - Active - - - On heating - Occupied Disable No Remote On
- - - Active - - - On auto - Occupied Disable No Remote On
- - - - Active - Enable - - Occupied Disable No CCN On
- - - - - Active - - Local Occupied Disable No Local On
- - - - - Active - On cooling Remote Occupied Disable No Remote On
- - - - - Active - On heating Remote Occupied Disable No Remote On
- - - - - Active - On auto Remote Occupied Disable No Remote On
- - - - - Active Enable - CCN Occupied Disable No CCN On
To Next Page
Loading...
Need help?
General
