889-2106-03
Model U-1400 Operations Manual Rev Apr 2020 Page
9
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channel reset or until the Loop Check function is turned off. During a check loop failure the LCD will flash
Lcl
.
NOTE: If the Loop Check Timer is set to 0 minutes, the Loop Check function is off.
S
YNCH
M
ODE
: The Synch feature provides a means of linking up to four U-1400 detectors together. There are two
modes in which the detectors can be configured to operate, Series Synch or Parallel Synch.
Series Synch mode can be used to eliminate the possibility of crosstalk between adjacent loops. Series Synch will
activate one loop at a time, cycling through all loops configured to detect in the Series Synch mode. When the
detector system is configured to operate in Series Synch mode, it is necessary for one detector to be identified as
the master unit, i.e. the detector that starts the Synch pulse. This master unit must be assigned a Detector ID value
of 000. The scanning sequence of detector loop input channels is Detector ID 000 channel 1, Detector ID 000
channel 2, Detector ID 000 channel 3, Detector ID 000 channel 4, second detector channel 1, second detector
channel 2, second detector channel 3, second detector channel 4, and so on until the synch pulse returns to the first
detector. The Synch-out of the first (master) unit is connected to the Synch-in of the second detector; the Synch-
out of the second detector is connected to the Synch-in of the third detector. This connection scheme is continued
until the Synch-out of the last detector is connected to the Synch in of the first (master) detector.
When set to operate in Parallel Synch mode, all detectors configured to operate in Parallel Synch mode start
scanning their respective channel 1 loop inputs at the same time and then proceed to sequentially scan their
respective channel 2, 3, and 4 loop inputs. When the detector system is configured to operate in Parallel Synch
mode, it is necessary for one detector to be identified as the master unit. This master unit must be assigned a
Detector ID value of 000. Connections between detectors differ from those in Series Synch mode in that the
Synch-out of first detector is connected to the Synch-in of the other detectors and the Synch-in of the first detector
is connected to the Synch-out of the other detectors.
(ID 000)
Synch
Out
Synch
In
Detector
2
Detector
Detector
4
Synch
In
Synch
Out
Synch
In
Synch
Out
Synch
In
Synch
Out
Reset
Reset
Reset
Reset
+
-
+
-
+
-
+
-
Series Synch Connections
Detector
(ID 000)
Synch
Out
Synch
In
Detector
2
Detector
3
Detector
4
Synch
In
Synch
Out
Synch
In
Synch
Out
Synch
In
Reset
Reset
Reset
Reset
+
-
+
-
+
-
+
-
Synch
Out
Parallel Synch
