Dwyer 275 User Manual
Page 6

In order to make the valve stem move fast, push
5. Push
Parameter Mode (PARAM)
Parameter types
There are four types in Parameter mode: Dead Zone, KP, KI, and KD.
These values are reflected as soon as they are changed, therefore the
appropriate values are found by checking the valve’s motion in real time.
Dead Zone (dEAdZONE)
This is the range of error % that the positioner is not adjusted. Hunting
or oscillation due to friction between the stem and packing is prevented
by this parameter.
KP
This is a proportion constant value that is correcting 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.
Adjustment of Parameter
Dead Zone (dEAdZONE)
1. Push
appears.
2. Push
3. Push
4. Push
5. Adjust dEAdZONE value by pushing
value is applied immediately without additional operation. Users can
easily check its adjustment by changing the current input signal to the
positioner. Optimum control value is found by adjusting values during
valve operation.
6. Push
LCD.
7. Push
KP
1-3. Adjustment method and procedure same as dEAdZONE.
4. Push
5. Push
6. Adjust KP values with
immediately without additional operation. Users can easily check its
adjustment by changing the current input signal to the positioner.
Optimum control value is found by adjusting values during valve
operation.
7. Push
8. Push
9. Push
page 6
Push
Push
Push
Push
Valve stem moves up slowly.
Valve stem moves up quickly.
Valve stem moves down slowly.
Valve stem moves down quickly.
Button operation for valve stem movement
(1) Push
seconds.
(2) Push
(3) Push
(4) Push
(5) Push
(6) MANUAL MODE.
(1) Push
seconds.
(2) Push
(3) Push
(4) Push
(5) Push
after adjustment by
(6) Push
(7) Push
RUN MODE.
(1) Push
seconds.
(2) Push
(3) Push
(4) Push
(5) Push
(6) Push
after adjustment with
(7) Push
(8) Push
RUN MODE.