Troubleshooting, 1 what to do first, 2 troubleshooting communications – Yokogawa YVP110 User Manual
Page 109: 3 troubleshooting function block parameters, Troubleshooting -1, What to do first -1, Troubleshooting communications -1, Troubleshooting function block parameters -1

<20. Troubleshooting>
20-1
IM 21B04C01-01E
20. Troubleshooting
20.1 What to Do First
When a problem occurs, check the following first.
Mounting of YVP110 Positioner
• Is the linkage to the valve actuator correctly set
up?
• Is the feedback lever correctly attached?
• Is the span of rotation angle of the position
sensor against the valve stroke more than the
minimum requirement?
• Has auto tuning been performed after
installation?
Air Piping
• Are the air pipes correctly connected? Is there
no leak of air?
• Is the air supply pressure high enough to drive
the valve?
• Is the A/M selector on the positioner set to A
(automatic)?
Wiring
• Is the YVP110 positioner correctly connected to
the fieldbus?
• Are the conductors incorrectly connected,
in other words, is the plus side connected to
minus, and vice-versa?
• Has the power to the fieldbus been turned on?
Is the terminal-to-terminal voltage equal to or
greater than 9 V?
• Is the terminator correctly installed?
• Is a host system connected to the fieldbus?
20.2 Troubleshooting Communications
Problem
Presumed Cause
Remedy
Ref. Section
Communication with
the YVP110 cannot be
performed.
Wiring is incorrect.
Correct wiring.
4.3, 8.4
The power is off or the power
supply voltage is less than 9 V.
Supply proper voltage.
4.3, Chapter 7
The address detection range is
not correctly set.
Correct address detection range.
9.4
Communication with the
YVP110 is frequently cut off.
The fieldbus is experiencing a
large amount of noise.
Using an oscilloscope or the
like, check the waveform on the
fieldbus.
—
The YVP110 can be
detected, but neither function
blocks nor transducer block
can be seen.
The node address of the YVP110
is left as the default (0xF8-0xFB).
Change it to an operable address.
See the descriptions for address
settings.
9.4
20.3 Troubleshooting Function Block Parameters
Problem
Presumed Cause
Remedy
Ref. Section
A value cannot be written to a
parameter in the YVP110.
You have attempted to write a
value outside the valid range.
Check the setting range of
parameters.
Appendix 1
The target mode does not allow
write access.
Change the target mode. See the
parameter lists.
Appendix 1
The actual mode of a
function block cannot be
equalized to the target mode.
O/S is set for the target mode of
the resource block.
Change the target mode of the
resource block to Auto.
Appendix 1, 10.1
The I/O of the function block
in question is not connected to
another function block.
Using a configuration tool, set the
virtual communication relationship
(VCR) and link object.
Chapter 9
Schedules that define when
function blocks execute are not
set correctly.
Set the schedules using a
configuration tool.
Chapter 9
The transducer block is in O/S
mode.
Change the target mode of the
transducer block to Auto.
Appendix 1, 10.1
A block’s dynamic
parameters do not update.
The block in question is in O/S
mode.
Change the target mode as
necessary.
Appendix 1, 10.1
O/S is set for the target mode of
the resource block.
Change the target mode of the
resource block to Auto.
Appendix 1, 10.1