TAC AB, 1999-08-18
0-004-7516-1 (GB), 5:15 (16)
TAC Xenta 102 Handbook
Functional description
5.3.7 Alarm
When TAC Xenta 102 reports alarms to a monitoring system,
this is done with the network variable nvoAlarmStatus. The
variable has 16 bits, which correspond to different alarm
situations.
Alarm conditions for nvoAlarmStatus
Bit no.
Alarm
Cuts out when...
Is reset when...
0
Deviating zone temperature
The deviation in zone temp. is
The deviation in zone temp. is
larger than
nciSpaceTempDev
smaller than the value in
for more than 60 min.
nciSpaceTempDev (hysteresis
(comfort mode).
0,5 °C).
1
Low zone temperature
The zone temp. is lower than the
The zone temp. is more than
value in
nciSpaceTempLow for
2°C above the value in
more than 60 min. (Economy and
nciSpaceTempLow.
off mode).
2
Window contact alarm
Energy hold off (window contact) The controller no longer
is enabled for more than 60 s.
detects the state.
(Economy and off mode).
3
High CO
2
level
The CO
2
level is 200 ppm higher
The controller no longer
than
nciSpaceCO2High for more
detects the state.
than 60 minutes (comfort mode).
4
Deviation in flow in VAV box
The deviation is larger than 10%
The controller no longer
of
nciMaxFlow for more than
detects the state.
30 min.
10
Not bound
nvi’s have not been
Power on
When the first not bound net-
received
work variable has been
received.
11
Adaptation of thermistor value Internal writing error in the
The controller must be
does not work
controller memory.
replaced.
12
Bound network variables not
Bound network variables have
When network variables have
received
not been received within set time. been received.
nciRcvHrtBt
13
Not valid value on input
A network variable for input goes The variable gets an accepted
outside its accepted value.
value.
14
No application program
No valid application program.
The application program is
loaded. Contact your nearest
TAC service point.
15
Cannot write to
The controller is faulty.
The controller must be
EEPROM
replaced.
Index Variable name
Description
3
nvoAlarmStatus
Alarm status output
26
nciSpaceTempDev Maximum deviation of zone temperature
27
nciSpaceTempLow Low limit of zone temperature
47
nciRcvHrtBt
Receive heartbeat
