Title:
POSITIONER
Document Type and Number:
Japanese Patent JP2017134563
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To prevent a malfunction caused by lightning surge, to eliminate the need for maintenance, and to allow automatic return to a normal mode from an emergency cutoff mode.SOLUTION: A positioner comprises a normal range stability determination unit 7 to monitor a comparison result within a comparator 5A (a comparison result held in a comparison result holding unit 52); when the comparison result changes from a comparison result indicating that the value of a control signal Is falls outside a normal range to a comparison result indicating that the value has returned to the normal range, measure a time for which the comparison result indicating that the value has returned to the normal range is maintained as a normal range maintenance time T; to determine whether or not the normal range maintenance time T exceeds a normal range stability determination time TS; to send the determination result to a comparison result output state adjustment unit 53; and to prohibit outputting to a control unit 1 the comparison result indicating that the value has returned to the normal range until the normal range maintenance time T exceeds the normal range stability determination time TS.SELECTED DRAWING: Figure 1
Inventors:
NARUMI KEISUKE
Application Number:
JP2016013020A
Publication Date:
August 03, 2017
Filing Date:
January 27, 2016
Export Citation:
Assignee:
AZBIL CORP
International Classes:
G05B9/02; F15B9/09
Attorney, Agent or Firm:
Shigeki Yamakawa
Masaki Yamakawa
Masaki Yamakawa