13
12.4
95-8616
CALIBRATION PROCEDURE
NOTE
When attaching or removing the calibration cup,
push or pull the cup with a slight
clockwise
twist.
Turning counterclockwise can cause the filter
assembly on the GT3000 to loosen. If the filter
assembly is inadvertently loosened, tighten it by
hand (no tools required).
Toxic and Hydrogen Sensors
1. Clean air must be present at the GT3000 sensor
module prior to initiating calibration. The use of
bottled air is recommended.
2. Initiate calibration by momentarily holding the
calibration magnet against the designated location
on the sensor module (see Figure 13) until the
green LED turns off and the yellow LED turns on
steady (approximately one second). Remove
the magnet when the green LED turns off. The
detector immediately begins taking zero readings.
Calibration can also be initiated via HART interface
(see Appendix F) or the UD10 (see manual number
95-8618).
3. When the zero calibration is complete, the yellow
LED changes from steady to blinking. Apply the
calibration gas to the sensor.
4. When the yellow LED turns off, remove the calibration
gas. The gas level at the sensor gradually returns to
zero. The green LED turns on steady to indicate that
the device has returned to normal operation, using
the new calibration data.
NOTE
The calibration procedure must be completed
within a ten minute period. If the calibration is not
completed, a calibration fault will be generated
and the transmitter will continue to use the
previous calibration data.
NOTE
To ensure reliable detection performance,
calibration should be performed at regularly
scheduled intervals. Various factors affect the
time interval between periodic calibrations
(typically 30, 60, or 90 day intervals, depending
on the ambient conditions).
NOTE
Calibration of ammonia sensor is recommended
any time the sensor has been exposed to 90 ppm
ammonia.
Oxygen Sensor
1. Using the magnet, activate the magnetic calibration
switch on the GT3000. The green LED turns off and
the yellow LED turns on steady.
2. The device automatically performs the zero
calibration.
3. When the yellow LED on the GT3000 flashes, the
device automatically performs the span calculation.
If using bottled 20.9% oxygen, apply immediately.
4. After successful calibration, the yellow LED turns off
and the green LED turns on steady to indicate that
the device has returned to normal operation, using
the new calibration data. Remove calibration gas (if
used).
LED
PLACE MAGNET HERE
TO ACTIVATE INTERNAL
MAGNETIC SWITCH
B2452
Figure 13—Location of Magnetic Switch on GT3000 Detector
