2. OPERATION
2.1Calibration
2.1.1All units are shipped from the factory calibrated, direct acting.
2.1.2If the user requires a different mode of operation (i.e. reverse acting, split range) it is necessary to reposition inter- nal electrical switches as indicated below. Though the units are factory calibrated for direct acting it is suggested that the user check the calibration.
2.1.3It is not necessary to remove the cover of the unit for calibration if the direct acting mode is desired.
2.2Direct Acting Calibration
2.2.1In direct acting operation the unit is calibrated so that minimum input signal corresponds to minimum output pressure and increasing input signal results in increasing output pressure.
2.2.2Apply the minimum input signal of the range being used (e.g. 4mA for a
2.2.3Observe the output pressure. If necessary, adjust the zero screw until reaching minimum output pressure setting. Turn zero screw clockwise to decrease and counter clockwise to increase.
2.2.4Apply the maximum input signal of the range being used (e.g. 20mA for a
2.2.5Observe the output pressure. If necessary, adjust the span screw until reaching maximum output pressure setting. Turn span screw clockwise to decrease and counter clockwise to increase.
2.2.6After setting the span it will be necessary to recheck the zero. Repeat steps
Figure 6 - Zero Adjustment and Span Adjustment
Zero Adjustment |
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Figure 7 - Direct Acting - Position of switches for forward acting operation (all output ranges).
Standard setting as supplied by factory.
Signal |
Page 6