what sud u do if u dont get feedback from control valve?
Answer Posted / carl_ellis
There's two kinds of feedback from a control valve:
a) the change of the process variable because the valve
position changes
b) position feedback directly from the positioner to the
controller/control system.
We'll assume that the question is directed at the loss of
position feedback signal from the loop's positioner.
1) Position feedback cards are options on smart
transmitters and need to be initialized after installation.
Has it been initialized?
2) DC power is typically loop power for position feedback.
Is the loop power supply still functioning?
3) Has the position feedback card or its wiring been
disabled or removed?
4) If the position feedback loop is intrinsically safe, is
the loop's I/S barrier open circuited?
5) Has the loop wiring been changed in some manner so as to
affect the position feedback signal integrity?
Carl Ellis
Measure First
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Yokogawa CENTUMVP R6.09 unable to download to Engineering Station with ExaOPC R3.75
The issue is when I try to download the common project section to the Engineering Station (STN) from the HIS in System View, it is unable to connect. The error displayed is:
WARNING: Could not connect to equalize destination. (7001)
Retrying. Number of retries = 0/1
ERROR: LdXopsLoadMain: connect error 10060
ERROR: Processing terminated due to connection error. (7002)
Equalization end with errors. STN0149
---- ERROR = 2 WARNING = 1 ----
Background:
>Updated the ExaOPC software on the STN from 3.60 to 3.75
>STN operating system is Windows Server 2008 R2
>HIS operating system is Windows Server 2016 Stanard
Solutions attempted include:
>Ensuring all IP addresses are correct and all networked devices can be pinged.
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