FujiFilm PXG4, Operation Manuals

Page: 109 / 158

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9
Chapter
Control Target
This controller has three valve control functions.
Select the best function for the current application.
●
Valve Control Functions
Servo Control 1/Servo Control 2
Adjusts and controls the motorized valve opening through
[OPEN], [CLOSE] connection points.
In manual mode, press the key to switch between [OPEN]
and [CLOSE].
Servo control 1 and servo control 2 have the following differences.
•
Servo Control 1: No valve opening display
•
Servo Control 2: Has valve opening display
Neither control can be used to control the valve opening itself.
Changing to Servo Control 1 or Servo Control 2
Servo control 1
(
Srv1 )
Controls the motorized valve opening
through [OPEN], [CLOSE] connection
points.
Servo control 2
(
Srv2 )
Controls the motorized valve opening
through [OPEN], [CLOSE] connection
points. The opening of the valve can be
displayed by reading the open position
signal from the motorized valve, but it
cannot be used in control output
calculations.
Position feedback
(PFB) control
(
pfb )
Inserts controls by adding the opening
signal from the motorized valve to the
control calculation results. Controls the
motorized valve opening through [OPEN],
[CLOSE] connection points.
This control can be used when there are
opening signals coming from the motorized
valve.
Point
• Servo control 1 can control the motorized valve even without a
valve opening signal from the motorized valve. (The motorized
valve opening is estimated from a calculation of the valve
stroke time.)
• Servo control 2 adds the valve opening signal display function
to servo control 1. Valve position display can be used to
automatically or manually adjust zero/span.
motorized valve
OPEN connection output
CLOSE connection output
valve opening
(servo 2/PFB)
measured value input
(temperature)
boiler
valve motor
(servo 1)
1
Press and hold the key to display the setup
mode channel menu ("
ooo oPPPPEEEE CCCChhhh1111
"), then use the
keys to display SYS ("
SSS
SYYYYSSSS CCCChhhh 7777
").
Refer to
See p. 93 in this chapter for information on how to display
the channel menu.
2
Press and hold the key then use the
keys to display CTrL ("
CCC
CTTTTrrrrLLLL
").
3
Press the key, then use the keys to
select Srv1 ("
SSS Srrrrvvvv1111
") when the bottom part of the
display begins to blink.
This chooses "Servo Control 1".
4
Press the key to confirm the setting.
5
Press the key to return to the operation mode
PV/SV display.
Point
• Adjustments must be made to display the valve opening.
• See "Position feedback (PFB) control" (p. 108, 128).
• An interlock function is built in. (except for PXG4)
Caution
Chattering may occur if the dead band ("
PGAP
") in the PFB
menu ("
PFB Ch10
") is set too small.