Basic Documentation

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Siemens VAV compact controller G..B181.1E/3 | VAV modular controller ASV181.1E/3 CE1P3544en
Smart Infrastructure 2021-10-26
9.2 Parameters and function description
9.2.1 Vnom (nominal volume flow) [m
3
/h or l/s]
VAV boxes are ordered through an OEM according to this nominal volume flow and
min. / max. volume flow settings. The maximum volume flow for ventilating a room /
zone can’t be higher than the nominal volume flow.
9.2.2 Vmin / Vmax (minimum / maximum volume flow) [%]
These values limit the nominal volume flow and are relative to Vnom. Their effect is
described in chapter 5.
9.2.3 Elevation above sea level [m]
This value enhances the accuracy of the differential pressure sensor to
compensate for the air density decreasing with increasing altitude. It can be set in
500m steps, so for a given building the setting closest to the actual altitude is to be
used.
Example: Altitude of building: 420m a.s.l. → use setting “500m”
9.2.4 Override control
The actuator can be operated in override control for checking / maintenance
purposes or system-wide functions (e.g. night-cooling).
9.2.4.1 Local override:
The actuator enters this state when a service tool is connected at the service
interface (PPS2).
• Open / Close (depends on opening direction)
• Stop
• If the actuator is in backup mode, it will be controllable in local override but
resume the backup mode
- when the service tool is disconnected,
- when the local override timeout is exceeded, or
- when the override control is set to “off”.
• Timeout is 60s after the last read or write access resp. after disconnecting the
service tool.
9.2.4.2 Remote override:
When the setpoint signal range (YC) is set to DC 2…10 V, the actuator can be
driven to "fully closed" by setting YC = 0 V. The hysteresis behavior is shown in the
diagram below.