Det-Tronics R8471NH34001,2,3 Single Channel Gas Controller, NH3 - Manual (Page 19)

17 95-8529 1.1
2. At the end of the two second interval, the Low
LED goes out, the High LED blinks, and the digital
display shows the high alarm setpoint.
3. Two seconds later the High LED goes out and the
Auxiliary LED blinks. The digital display now shows
the auxiliary alarm setpoint.
4. Two seconds later the Auxiliary LED goes out and
the CAL LED blinks. The digital display now shows
the programmed calibration gas time.
5. After displaying the calibration gas time for two
seconds, the controller automatically leaves the
Setpoint Display mode and returns to the Normal
operating mode.
6. If adjustments to the setpoints are required,
perform the Setpoint Adjustment procedure. When
the setpoint levels are acceptable, record this
information for future reference.
SETPOINT ADJUSTMENT PROCEDURE
1. Determine the required alarm setpoint levels and
calibration gas time.
2. Press and hold the Set button for one second, then
release. The digital display indicates the present
low alarm setpoint and the Low LED blinks. Press
the Reset button to increase the reading or the Set
button to decrease the reading. (Holding the button
will cause the reading to change rapidly.)
3. When no changes to the setpoint level have been
made for 5 seconds, the Low LED goes out, the
High LED blinks, and the digital display shows the
high alarm setpoint. Press the appropriate button
(detailed in step 2 above) to obtain the desired
reading on the digital display.
4. When no changes to the setpoint level have been
made for 5 seconds, the High LED goes out, the
Auxiliary LED blinks, and the digital display shows
the auxiliary alarm setpoint. Press the appropriate
button to obtain the desired reading on the digital
display.
5. When no changes have been made for 5 seconds,
the Auxiliary LED goes out, the CAL LED blinks, and
the digital display indicates the calibration gas time.
Press the appropriate button to obtain the desired
reading on the digital display.
6. When no changes have been made for 5 seconds,
the controller automatically returns to the Normal
operating mode.
7. Record the new values for future reference.
NOTE
The alarm setpoints, calibration gas time, and
calibration data are stored in non-volatile memory
and are retained in the event of a power loss.
However, if power is interrupted while performing
the Setpoint Adjustment or Calibration procedure,
the entire procedure must be repeated when
power is restored.
CALIBRATION
SENSOR RESPONSE CHARACTERISTICS
In order to ensure that the gas detector will provide
maximum protection, it is important to understand the
operating characteristics of the sensor being used.
This is particularly true in the case of electrochemical
Cl
2
, SO
2
or NO
2
sensors, since their response is
different than that of other gas sensors.
Figure 15 shows the response curve of a typical
sensor that has not been exposed to gas for 30 days
or longer.
TIME
OUTPUT
Figure 15—Response Curve of a Typical Sensor