Flowserve Logix 520MD+ User Instructions Download

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User Instructions - Logix® 520MD+ Series Digital Positioner

FCD LGENIM0105-00

Field Trial Version – Printed October 28, 2011

While  the  calibration  is  in  progress,  the  LED  lights  will  flash
status codes  indicating  the calibration  progress.  See section
17.3  Status  Code  Descriptions  for  an  explanation  of  the
status code sequences.

The  initial  calibration  of  extremely  large  or  very  small
actuators  may  require  several  calibration  attempts.    The
positioner  adapts  to  the  actuator  performance  and  begins
each  calibration  where  the last  attempt  ended.    On an initial
installation  it  is  recommended  that  after  the  first  successful
calibration  that  one  more  calibration  be  completed  for
optimum performance.

8.4.1

Quick Calibration Switch – Jog

Set  the  Quick  Calibration  Switch  to  Jog  if  the  valve/actuator
assembly  has  no  internal  mechanical  stop  at  the  fully  open
position.   In this case, follow these instructions:

1

Press and hold the

►

ACCEPT/QUICK-CAL button for

approximately 3 seconds.

This will initiate the jog stroke calibration.  The positioner will
then  close  the  valve  and  set  the  zero  position.    The  zero
position is automatically always set at the valve seat.  At this
point  the  LED‘s  will  flash  in  a  sequence  of  G-R-R-R  (green-
red-red-red)  which  indicates  that  the  user  must  use  the  jog
keys to manually position the valve to approximately 100%.

2

Use the up and down keys to position the valve at
approximately 100% open.

Press the

►

ACCEPT/QUICK-CAL button to proceed.

No  more  user  actions  are  required  while  the  calibration
process  is  completed. When  the  lights  return  to  a  sequence
that starts with a green light the calibration is complete.

The jog calibration process will only allow the user to set the
span.    If  an  elevated  zero  is  needed  a  handheld  or
ValveSight DTM are required.

8.4.2

Tuning Options

Quick-Cal Custom Gains - This is typically the fastest way to
achieve ideal gains.  Set the Auto Tune Configuration Switch
to On and the Selectable GAIN Switch to “E”.  Then perform
a  Quick-Cal.    During  the  Quick-Cal,  custom  tuning
parameters will be determined based on measured response
parameters.    The  gains  can  then  be  fine-tuned  by  adjusting
the  Selectable  GAIN  Switch.    Selecting  “D”  “C”  or  “B”  will
progressively provide a more stable response.  Selecting “F”
through “J” will progressively provide a more active response.
In most cases selecting “E” will give the best results.  This is
the default setting for all actuator sizes.  Raising or lowering
the  Selectable  GAIN  Switch  setting  is  a  function  of  the
positioner/valve  response  to  the  control  signal,  and  is  not
actuator size dependent.

Standard  Preset  Gains  -  If  standard,  preset  gains  are
desired, set the Auto Tune Configuration Switch to Off.  After
performing  a  Quick-Cal,  use  the  Selectable  GAIN  switch  to
the  desired  level  (“B”  –  “J”).    The  standard,  preset  gain
settings  are  not  affected  by  Quick-Cal.  It  may  be  necessary
to  set  the  gain  switch  before  the  Quick  Cal.    Very  fast
stroking valves may need to be at lower gains and very slow
stroking valves may need to be at higher gains.

It  may  be  necessary  to  set  the  gain  switch  BEFORE  the
Quick Cal.  Very fast stroking valves may need to be at lower
gains and very slow stroking valves may need to be at higher
gains.

Custom  Manual  Gains  -  To  set  gains  manually,  set  the
selectable GAIN switch to “A”.   Changing the switch from “B”
to  “A”  will  write  the  standard  “B”  settings  into  the  “A”

parameters,  allowing  a  starting  point  for  modification.
Similarly,  changing  the  switch  from  “J”  to  “A”  will  write  the
standard “J” settings into the “A” parameters.  Custom tuning
values  can  then  be  entered  using  the  Display  Menu,  a
Handheld  or  ValveSight  DTM.    With  the  Selectable  GAIN
Switch  set  to  “A”,  the  tuning  will  not  be  modified  during  a
Quick-Cal.

8.4.3

Aborting a Quick-Cal

The Quick-Cal can be aborted at any time by briefly pressing
the

►

ACCEPT/QUICK-CAL button again. In this case, the

previous settings will be retained.

8.4.4

On Line Stroke Calibration Adjustments

At  times  an  adjustment  to  the  calibration  is  desired,  but  the
process cannot be interrupted.  The stroke calibration can be
adjusted  with  minimal  valve  movement.    Contact  your  local
Field Service Technician for more information.