[DB600] General instruction manual
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6-7-2
Manual adjustment
(1) Initialization of setting value
Before starting the adjustment, change the settings of "Feedback zero/span (MODE6)" and
"Feedback dead band (MODE6)" to defaults (feedback zero: 0.0%, feedback span: 100.0%,
feedback dead band: 4.0%).
Check that the parameters are set to ensure the output range of 0 to 100%.
(2) Zero adjustment
Switch the operation mode of the instrument to MANUAL output and set the output value to 0.0%.
Let the actuator jump the scale at the CLOSE side (output display "O1" lights).
Increase the output value by 0.1% at a time to obtain the value at which the output display "O1" on
the operation screen turns off.
(3) Span adjustment
Set the output value to 100.0%.
Let the actuator go off the scale at the OPEN side (output display "O2" lights).
Decrease the output value by 0.1% at a time to obtain the value at which the output display "O2" on
the operation screen turns off.
(4) Zero/span adjustment
Set "Feedback zero/span (MODE6)" to the output values obtained in (2) and (3).
(5) Deadband adjustment (gain adjustment)
Set the output value to 50.0%.
Increase the setting value of "Feedback dead band (MODE6)" by small increments to obtain the
dead band of OPEN relay drive (output display "O2" lights) and CLOSE relay drive (output display
"O1" lights).
Then perform a trial operation and increase the setting value by small increments to find the
maximum value in the range that does not adversely affect the controllability. Use the maximum
value as an eventual feedback dead band setting value.