Basic Documentation

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Siemens VAV compact controller KNX/PL-Link G..B181.1E/KN CE1P3547en
Smart Infrastructure 2021-10-25
9.4 Alarms in LTE mode (ACS790)
The following alarms are available in ACS790.
Alarm ID
Alarm text
Description
What to do
0
No alarm
5020
Communication error
Backup mode entered
• Check connection to room
controller / thermostat
• Resolved when new setpoint is
received
90
Diff. pressure sensor
error
Internal sensor error
• Check pressure tubes and
nozzles for dirt
• Restart device
• Problem persists: Contact
customer support
91
Diff. pressure sensor
tubes interchanged
Tubes interchanged at
P+ and P-
• Change tubes connection
1921
Expected operating
hours
Appears after a
cumulated motor running
time of 365 days
• Check device status and control
loop sensitivity
• Problem persists: Contact
customer support