UTC Fire and Security Det-Tronics R8471B Instructions Manual page 10

— Low and/or Auxiliary LED flashes.
— Low and/or Auxiliary alarm output changes state.
— DC current output signal level corresponds to sen-
sor input.
— Fault output energized and LED off.
When the signal decreases below the low or auxiliary
setpoint:
— Digital display, bar graph display, and 4 to 20 ma
output continue to track the sensor input.
— With latching operation programmed: No change
to alarm outputs.
— With non-latching operation programmed: Alarm
outputs return to their normal state.
— Low and Auxiliary LEDs are on steady until reset.
In the Normal operating mode and a high alarm con-
dition occurring:
— Same as a low or auxiliary alarm condition, but
High LED and high alarm output are affected.
When the signal decreases below the high alarm set-
point:
— The high alarm is always latching and unaffected
by the latching/non-latching programming for the
low and auxiliary alarms. High LED is on steady
until reset.
In the event of a system fault:
— The normally energized Fault output is de-ener-
gized and the FAULT LED is illuminated.
RESET
The Reset mode is entered by pressing the
RESET button located on the front panel of the
controller. (See Figure 5.) When the RESET button
is momentarily depressed, all LEDs turn off and all
outputs return to their normal condition if no alarms or
faults are occurring (basic reset). When the RESET
button is held for 0.5 second, the LEDs turn off and
the outputs return to their normal condition even if
an alarm or fault condition still exists (forced reset).
Remote reset capability is also provided. (Remote
reset performs a forced reset.)
2.1
The remote reset performs a reset function only.
It cannot be used for entering other controller
operating modes.
SETPOINT DISPLAY MODE
If the RESET button is held for approximately
one second, the controller enters the Setpoint
Display mode. In this mode, the digital display
sequentially shows the programmed alarm setpoints
and calibration gas concentration. Each value
is displayed for approximately 2 seconds. After
completing the sequence, the controller automatically
returns to the Normal operating mode if the RESET
button is no longer being depressed.
This mode is used only for displaying the setpoints.
Use the "Setpoint Adjust" mode for changing setpoint
and calibration gas values.
CALIBRATE
The R8471B Controller uses a fully automatic
calibration procedure that requires no adjustments
by the operator. The Calibrate mode is entered
by pressing and holding the RESET button until
completion of the "Setpoint Display" sequence
described above (approximately 9 seconds). The
controller performs the Zero adjustments, then signals
the operator when to apply and also when to remove
the calibration gas. Upon completion of a successful
calibration, the controller automatically returns to the
Normal operating mode.
If the operator fails to complete the calibration
procedure, if an error in calibrating occurs, or if a
successful calibration cannot be completed, the
microprocessor will automatically return to the Normal
mode (after 10 minutes or when the gas level drops
below the lowest setpoint) and continue to use the
previous calibration data. A fault indication ("F2X"
status) will be displayed until a reset occurs. If the
microprocessor determines that the sensing element
is approaching the end of its useful life, "F10" will
be indicated on the digital display. Refer to the
"Calibration" section of this manual for complete
information regarding calibration.
While in the Calibrate mode, all controller outputs
are inhibited, the CAL LED is illuminated, and the dc
current output goes to a preset level (adjustable from
0 to 20 ma).
8
NOTE
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