Process instrumentation requires periodic calibration and maintenance to ensure that it is operating correctly.
Field checking a loop-powered isolator Fluke loop calibrators have a unique current simulation feature that, when connected to an external power source, allows you to precisely control current between 0 mA and 24 mA. When field checking a loop-powered isolator, the two-wire loop transmitter supplying signal current to the isolator for the loop may be removed and the calibrator connected in simulate mode to control loop current.
Testing valve positioners Electronic valve positioners should receive periodic in-field calibrations as part of preventive maintenance programs. Fluke loop calibrators are the ideal test tools for these checks. Valve positioners vary in design and valve type and should be calibrated using specific instructions from the individual manufacturer. Quick operational checks can be performed using a field calibrator as a signal source while observing the valve stem position, mechanical position indicators or flow indicators as input changes are made. Fluke loop calibrators provide a convenient source for simulating the controller output to a valve positioner.
Using Fluke Loop Calibrators as a voltage source A precision shunt resistor may be used to derive voltages for calibration using the calibrator’s current source mode. Using this system, Fluke loop calibrators are capable of generating voltages for devices with input spans as low as 10 mV to as high as 24 V.
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