Det-Tronics R8471J Single Channel Gas Controller, OPECL - Manual (Page 11)

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SETPOINT ADJUSTMENT
The R8471J Controller has independent Low, High, and
Auxiliary alarm setpoints, with corresponding outputs.
The calibration gas concentration in % full scale (0-5
LFL-m) is also displayed with the alarm setpoints.
The adjustment range for the alarm setpoints is as
follows:
Low alarm 5 to 50% full scale (0.25-2.5 LFL-m)
High alarm 10 to 60% full scale (0.5-3.0 LFL-m)
Auxiliary alarm 3 to 90% full scale (0.15-4.5 LFL-m)
Calibration gas 50% full scale
(2.5 LFL-m)
WARNING
Calibration gas concentration is set to 50% full
scale (2.5 LFL-m) at the factory and must
not
be changed. Other calibration gas settings can
cause unreliable readings, which could result in a
fire or explosion.
The factory settings are:
Low alarm: 20% full scale (1.0 LFL-m)
High alarm: 50% full scale (2.5 LFL-m)
Auxiliary alarm: 50% full scale (2.5 LFL-m)
Calibration gas: 50% full scale (2.5 LFL-m)
To check the present levels, use the “Setpoint Display
Mode”. To change the values, use the “Setpoint
Adjustment Procedure”.
SetPoInt DISPlaY MoDe
1. To enter the Setpoint Display mode, press and hold
the Reset button until the Low LED begins to blink
(approximately one second). Release the Reset
button. The low alarm setpoint will be shown for two
seconds on the digital display.
NOTE
The Reset button should be released as soon as
the controller has entered the Setpoint Display
mode (after one second). If the button is still
depressed at the end of the Setpoint Display
mode (9 seconds), the controller will automatically
enter the Calibrate mode. If the operator is not
prepared to perform a calibration, a calibration
fault will occur. Recycle power to the controller
to exit the calibrate mode without affecting the
calibration settings.
2. At the end of the two second interval, the Low LED
goes out, the High LED begins to blink, 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 programmed auxiliary alarm setpoint.
4. Two seconds later the Auxiliary LED goes out and
the CAL LED blinks. The digital display now shows
the calibration gas concentration. This value must
always read 50% full scale when an OPECL detector
is used with the R8471J.
5. After displaying the calibration gas concentration 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 and perform the
Calibration procedure.