MKS 1253D, Инструкция по эксплуатации

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Chapter Four: Operation General Information
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Chapter Four: Operation
General Information
The Type 153/1253 controller accepts pressure or position set points from an external computer
(via RS-232) or an external analog voltage source, and use an internal digital “PID” algorithm to
determine valve position. When the unit is configured for pressure set points, the feedback is an
analog pressure signal. This signal is normally 0 to +10 Volts, but the zero and full scale
voltages can be adapted to individual applications. (Refer to Calibration, page 44, for more
information).
The GAIN and LEAD constants used in the control algorithm are set at the factory but you can
change these parameters in the field via the RS-232 port, using either a portable terminal or a PC
computer.
When the set point is a position control command (Refer to Internal Controls on the 153/1253
Controller, page 34, for details on how to set this command), the valve is moved as a result of
the position control command, and no feedback signal is generated.