MKS Mass-Flo 1179A, Инструкция по эксплуатации

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Chapter Four: Operation How To Use the Optional Input (MFC only)
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How To Use the Optional Input (MFC only)
The 1179 and 2179 units provide an optional input feature which allows them to control flow
based on 0 to 5 V signals from external sensing devices. A common application of this feature is
pressure control using inputs from a pressure transducer.
Implement the optional feature by simply routing the output from the desired external device to
the appropriate “optional input” position for the particular connector. Refer to Table 8, page 34,
and Table 7, page 33, for the pinout assignments. Voltage to the optional input overrides the
signal generated by the unit’s own internal flow sensor. The control electronics drives the valve
so that the optional input signal matches the set point. Provide the 0 to 5 V set point to the same
input pin as in standard flow control.
Metered flow output is still available on the standard output pin identified in the applicable pin
assignments. Refer to Table 8, page 34, and Table 7, page 33, for the pinout assignments.