Detcon 12B - Manual (Page 13)

Model 12B
12B Control Module Instruction Manual Rev. 1.4 Page 9 of 12
9.2 Display/Alarm Test
To perform the display/alarm test, press and hold the alarm reset button for about five seconds until the fault
LED illuminates. Next, press and release the alarm reset button twice. The alarm 2 LED will illuminate
indicating that this test has been selected. The test will begin automatically within five seconds. Normal
operation resumes when the test is complete.
The test will begin by displaying an incremental count up from the bottom of the range (0) to the top of the
range with the count changing approximately three times each second. The exception to this is oxygen
monitoring which will begin its count at the top of the range and go down. As the count reaches an alarm set
point, that alarm will activate both LED and relay. When the count reaches the top of the range it will hold
there briefly to allow verification of the flashing over-range feature before it begins the count back down to
zero. As the test counts down below an alarm set point, that alarm will de-activate. If the alarm is programmed
for latching operation it will remain active. After the test is complete and the control module returns to normal
operation, the alarm reset button can be pressed to de-activate latching alarms. If the actuating of alarm relays
during this test is problematic, alarm relays can be disabled by toggling the alarm disable switch into the
disable (down) position.
9.3 RS-485 Address Setting Test
To perform the RS-485 address setting test, press and hold the alarm reset button for about five seconds until
the fault LED illuminates. Next, press and release the alarm reset button three times. The alarm 3 LED will
illuminate indicating that this test has been selected. The test will begin automatically within five seconds and
will terminate automatically when completed.
The test will simply display the RS-485 address setting for approximately four seconds and then return the
control module to normal operating mode.
10.0 OTHER FEATURES
Model 12B control modules include other features which are discussed below.
10.1 Flashing Over-range
The flashing over-range feature will cause the display to flash on and off, at approximately one second
intervals once the top of the range has been exceeded. After the signal drops back into the normal range, the
display will cease flashing and operate normally.