Dwyer 275 - Manual (Page 5)

RUN Mode
After connecting power to the positioner, the following is displayed on the
LCD in 6 seconds.
RUN on the bottom line means that the Smart Positioner adjusts valve
stroke based on an outside signal (4-20 mA) and PV refers to the
number on the LCD. In RUN mode, valve stroke is changed according
to input signal.
There are six options in RUN mode. In order to change RUN display
modes, hold and press or to scroll through
display options.
First Auto Calibration
First auto calibration is usually used when the positioner has not been
set, such as the initial setting with valve at the valve company or
replacement with other product in the field.
Notice: When the positioner is installed on the valve in the field after
setting, we recommend using AUTO1 calibration rather than AUTO2
calibration. This is because the AUTO 2 calibration parameters have
been factory set to the optimum settings.
KP
This is a proportion constant value that is correction by error %. If this
value is too big, there can be hunting, even though it finds position by the
input signal. If the value is too small, accuracy gets worse.
KI
This is an integral constant value adding or subtracting the correction
that is corrected error % on the previous correction signal. If this value
is too big, there can be oscillation. If it is too small, the time to find the
exact position increases.
KD
This is a differential constant value adding the previous correction signal
with the changing correction signal by the error % change rate.
RA/DA
Direct acting (DA) or Reverse acting (RA).
Auto Calibration Types
Auto 1 Calibration (AUTO1)
In this mode, all parameters necessary for valve operation are set except
KP, KI, KD. It is used to re-execute calibration by users in the field after
being supplied the postitioner unit whose parameters were set by the
valve company.
1. Push for 6 seconds in RUN mode and AUTO CAL
message should appear.
2. Push and then AUTO1 mode is displayed.
3. Push again at AUTO1 mode and Auto 1 calibration is started.
4. When Auto 1 calibration is done, ‘COMPLETE’ message appears on
the LCD. After 4 seconds the procedure returns to RUN mode and
the valve stroke by current input signal is displayed as a percentage.
Auto 2 Calibration (AUTO2)
All parameters necessary to operate valve are set. This calibration is
used when the positioner is first installed with valve. Refer back to First
Auto Calibration.
Auto 3 Calibration (AUTO3)
All parameters necessary to operate valve are set except zero and end
point. This function is used to re-execute auto calibration without
changing the zero and end point after adjusting them manually.
1. Push at AUTO2 and AUTO3 is displayed.
2. Push and AUTO3 calibration is started. The remaining
procedures of this calibration are the same as other calibrations.
BIAS Calibration
BIAS is the standard value of motor control in the positioner. It is affected
by supply pressure, KP and other values. BIAS should be re-adjusted if
supply pressure or KP is changed, otherwise accuracy will decrease.
1. Press and hold for 6 seconds in RUN mode and AUTO
CAL message should appear.
2. Scroll with button until BIAS mode is displayed.
3. Push and BIAS calibration is started.
4. When BIAS calibration is done, ‘COMPLETE” message appears on
the LCD. After 4 seconds the procedure is returned to RUN mode.
Velocity Calibration (V_0)
This function is used to find the standard value to recognize accurate
valve speed. This value must be correct for KI control to work properly.
To check if velocity value is correct:
1. Push button at RUN mode and RUN Vel is displayed.
2. Check the number on the bottom of the screen. Normally, the value
will be between -2 and 2.
3. If value is greater than 5, V_0 calibration is required.
To calibrate V_0:
1. Press and hold for 6 seconds in RUN mode until AUTO
CAL message is displayed.
2. Scroll with button until V_0 mode is displayed.
3. Push and calibration is started.
4. When V_0 calibration is done, ‘COMPLETE’ message appears on the
LCD. After 4 seconds the procedure is returned to RUN mode.
Manual Mode
Manual mode is used to raise or lower the valve stem manually. In this
mode, the valve stroke is adjusted only by operating buttons, not by the
current input signal. This mode does not affect controlling data
registered in the positioner. It only is used to move the valve stem up
and down.
1. Push at RUN mode until AUTO CAL message is
displayed.
2. Push and MANUAL mode is displayed.
3. Push again. Two lines appear on LCD. The upper line
indicates valve stroke by percentage and the lower line indicates
absolute value of inner resistance of the positioner. *MA means that
Manual mode is in operation.
4. Push or and valve stem moves up or down.
Regardless of RA/DA, if is pushed, valve stem moves up (in
case of linear valve). If is pushed, valve stem moves down.
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6 Run PV
Run SV %
Run SV mA
Run MV
Run Vel
Run Err Valve Stroke (%)
Input Signal (0 - 100%)
Input Signal (4 - 20 mA)
Motor/Piezo Valve Manipulate Valve (Digit)
Current Valve Stem’s Velocity (Digit)
Difference between SV and PV (%) Process Value
Set Value
Set Value
Manipulate Value
Velocity
Error
AUTO1
AUTO2
AUTO3
Zero Point
°
°
x
End Point
°
°
x
KP, KI, KD
x
°
°
RA/DA
x
°
°
(1) Keep pushing
for 6 seconds. (2) Push . (3) Push .
(5) Completed. RUN MODE.