Omega CN1001-TC, Руководство пользователя

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SECTION 16. PROPORTIONAL BAND (P.BND)
16.1 SELECTING PROPORTIONAL BAND (P.BND)
Proportional Band ( P.BND ) is not active unless your meter has analog output and relay capabilities.
The menu will display whether analog output is present or not.
• A proportional controller's output is linearly proportional to the change of the error signal,
whenever the signal is within 2 prescribed values (Proportional Band).
• There are three (3) points of interest on the proportional controller transfer curve.
• The first is the magnitude of the error signal that drives the controller to “full on” (e.g. 20 mA out
for 4-20 mA).
Figure 16-1. Controller Output
• The second point of interest is the magnitude of the error signal that drives the controller
output to “full off” (e.g. 4 mA out on 4-20 mA). These two (2) points need not be equally
spaced on either side of the zero error point.
• The third is the factor "Offset" and it is the output value of the controller which causes
zero error.
The above example illustrates the parameters for the 4-20mA analog out, likewise, analog
voltage output will have these (3) points of interest.
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