Emerson Rosemount 928, Reference Manual

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Note
If you need a long length of calibration tubing to reach the device, make allowances
for a delay in response time from the sensor while the target gas travels the length
of the calibration tubing.
A gas concentration begin to register on the device display and gradually increases
to the target gas concentration level.
4. Shut off the target gas flow at the regulator.
5. Detach the calibration tubing from the regulator on the target gas source to the IP
filter inlet on the bottom of the transmitter.
5.9 Calibration
Calibrate at least every 90 days throughout the detector's service life.
Refer to Calibrating the sensor .
5.10 Sensor storage
Follow these recommendations when storing the sensor.
• Store the sensor in its original sealed packaging with the IP filter side facing downward.
• To avoid damaging sensor electrodes, do not stack sensors on top of each other.
• Do not store or install the sensor in areas where it may be subject to solvent vapors.
Doing so may result in any or all of the following:
— Blocked sensor electrodes
— Damaged sensor electrodes
— Damaged sensor body
— False baselines
5.11 Replace the gas sensor
The sensor is connected to the transmitter assembly by means of two tabs, which fit into
the bottom portion of the housing. The seal between the transmitter housing and the
sensor assembly is designed so that the fit is airtight between the two assemblies when
the sensor is properly installed. Replace sensor if the tabs do not latch as intended.
Sensor life varies based on the sensing technology, the installation environment, and the
ambient conditions in that environment. Typically, electrochemical sensors last from one
and a half years to two years. You must replace a sensor when it cannot accept a new
calibration due to having reached the end of its service life.
Procedure
1. Remove the old sensor assembly by firmly grasping both tabs and squeezing them
together while simultaneously pulling downwards on the sensor assembly. If
necessary, apply a slight rocking or twisting motion to remove the sensor.
2. Install the new sensor assembly.
Reference Manual Operation and maintenance
00809-0100-4928 September 2019
Rosemount 928 161