Partlow MIC 1400 - Current Proportioning Control

MIC 1400 ManualEdition 1 37
Current Proportioning Control 4.6
Current Proportioning control can be implemented on units provided with
mADC current output(s). Current Proportioning control provides a 4 to
20mADC or 0-20mADC output in response to process value and setpoint.
As with Time proportioning, the calculated output % for Current proportion-
ing is affected by the Tune mode parameter adjustments.
See Figure 4-1 (below) for proportional bandwidth effect on the output.
FIGURE 4-1
Output 1
Output 2
Output 2
Output 1
Proportional
Band 1
Pb1
Proportional
Band 2
Pb2
Deadband
(negative value)
SPrd
Process Variable
Output Power (%)
Output 1
Output 2
Output 2
Output 1
Proportional Band 1
Pb1
Proportional Band 2
Pb2
Overlap
(Positive value)
SPrd
Process Variable
Output Power (%)
Output 1
Output 2
Output 2
Output 1
Proportional
Band 1
Pb1
Proportional Band 2
Pb2 = 0
Overlap/Deadband
Sprd
Process Variable
Output Power (%)
ON/OFF
Differential
HyS2
Output 2 OFF
Output 2 ON
Positive values Negative values
Setpoint
Setpoint
Setpoint