Weidmuller Portacal 275 - Signal source and loop calibrator - Manual (Page 12)

1
• Calibration
General
All instruments are fully calibrated before leaving the factory and should
not need adjustment until the next scheduled calibration.
Remove the case for access to the calibration adjustments.
Tap the potentiometer after each adjustment to make sure that the
reading remains stable.
Equipment requirements
• An accurate digital multimeter (accurate to 0.05 mV and ±0.1 μA)
• Flat bladed screwdriver (blade width less than .5 mm/0.1 inch)
Digital multimeters are frequently better at measuring voltages than
currents, so you may wish to measure the voltage across an accurate
standard resistor (say 10 Ω ±0.05 %) when monitoring current signals.
0-20 mA range adjustment
1. Set the ‘current range select’ switch to 0-0 mA.
. Set the ‘output level select’ switch to 100 %.
3. Set the ‘voltage/millivolt select’ switch to 00 mV.
. Set the ‘source/sink mode’ switch to Source.
5. Adjust potentiometer C until the output is 0 ±0.001 mA.
6. Set the ‘output level select’ switch to 0 % and check that the output
is below 0.0 mA.