RKI Instruments GD-K11D - Manual (Page 23)

Model GD-K11D Operator’s Manual Maintenance • 19
4. Pull the metal restraining bracket that secures the sensor in the housing away from
the sensor, then rotate the bracket to the right.
5. Slide the sensor to the left (toward the pump), then remove the sensor from the flow
chamber.
6. Disconnect the connector from the sensor, then remove the sensor from the housing.
Installing the replacement sensor
1. Connect the connector to the replacement sensor, then install the sensor in the same
position as the original sensor.
2. Place the metal restraining bracket in its original position to secure the sensor within
the housing.
3. Place the power switch in the ON position.
4. Allow the sensor to warm up for 30 minutes (2 hours for ammonia sensors) before
you continue with this procedure.
Entering the new K number
Each sensor is shipped with a K number written on the label. The K number is established
at the factory at the time of calibration. The K number allows the Model GD-K11D to
automatically set the span setting without introducing calibrating gas.
CAUTION: The K number is only valid for 3 months after shipment from the factory. If you
suspect the replacement sensor is beyond this 3-month limit, calibrate the
replacement sensor (see page 21) after you enter the K number.
1. Press the MODE button until the SKIP light begins flashing and 1. appears on the
display screen.
2. Press the ∆ button three times to display 4. on the screen.
3. Press the SET button to display the K number of the previous sensor.
4. Use the ∆ and ∇ buttons to adjust the value on the display screen to the K number of
the replacement sensor.
5. Press the SET button to enter the new K number.
The SPAN light is on steady (instead of flashing) to indicate the new K number is
entered.
6. Press the MODE button to display 4.
Setting the zero reading
CAUTION: If you suspect the presence of toxic gas in the monitoring environment, use the
calibration kit and the zero air calibration cylinder to introduce “fresh air” to the
sensor and verify an accurate zero setting.
1. Verify that the Model GD-K11D is in a fresh air environment (environment known to
be free of toxic gas.)
2. Press the ∇ button to display 3.
3. Press the SET button.
The ZERO light flashes, and the gas reading appears on the display screen. The Model
GD-K11D is prepared to adjust the zero reading.