MSA PrimaX IR, Руководство по эксплуатации

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PrimaX® IR
16
Start-up and Calibration
GB
4 Start-up and Calibration
4.1 Initial Startup
The device is factory-calibrated and ready for use. The device provides a 4 - 20 mA output signal that
can be used in conjunction with data acquisition controllers. The digital HART signal that is superim-
posed on the 4 - 20 mA output can be read by control systems that are in compliance with
HART Revision 7.0 format.
During device operation, the 4 - 20 mA output signal is updated once/second and provides the infor-
mation shown below:
*Output levels are customer configurable between 2.0 – 3.5 mA via the HART interface.
See the Hart Specification on the product CD for more information.
Transient Fault conditions will be automatically cleared when the unit recovers from the fault condition.
MSA recommends verifying proper response to changes in mA outputs by using the "Enter Fixed
Current Mode" command described in the PrimaX IR Link Help Guide to check the four fault conditions
noted with a
* above. These checks should be done at every calibration phase.
Calibrations
General
The calibration must be done at regular intervals in accordance with applicable national and regional
regulations.
The device is calibrated at the factory. Nevertheless, it is recommended to recalibrate the device after
installation. New sensors should be calibrated more often until the calibration records prove sensor
stability. The calibration frequency can then be reduced to the schedule set by the safety officer or plant
manager.
Signal
The 4 - 20 analogue signal is available within 1 minute of power-on but the device should be powered
for at least 60 minutes before attempting calibration to allow for temperature stabilization.
CAUTION!
Carry out the calibration during commissioning as well as at regular intervals. This ensures optimum
operation of the sensor.
4-20 mA Output Levels [Default Values]
OPERATION 4 - 20 mA Definition
SAFETY CRITICAL FAULT 0.0 mA
Sensor failure.
Communications not available to sensor
*FAULT 2.0 mA
Problem detected.
Status available via HART interface
*OBSCURATION OR DIRTY
OPTICS
2.5 mA Light path is blocked
*POWER UP OR SENSOR
CALIBRATION
3.0 mA
Unit power was recently applied or calibra-
tion in process with Cal Signal Enabled
*CLEANING MODE 3.5 mA Defined in chapter 5
NORMAL
Gas value scaled
from 4 - 20 mA
for 0 - 100 % LEL
OVERRANGE 20.0 - 20.5 mA > 100 % LEL gas is detected by the device