Technical Specifications

155
Step Response Test
Diagnostic Services
Num of Samples Sampling points of each step: range is 20 to 600 points.
Pause displays the delay before sampling begins. When the
step test begins, the valve operates and sampling begins. Once
the sampling number reached, it moves to the next step. The
time between the steps is Pause. Sample points are collected in
Pause time but due to command delay, sample points can also
be found on the graph when the valve is moving.
Initial Start Position
Error Limit (%)
The maximum error allowed between the actual position
(FINAL_POSITION_VALUE) and the user-selected Initial Set
Point before starting the test. The minimum value is 0.1 if the
step size greater than 0.2, otherwise the minimum value must
be greater than a half of the step size.
Initial Start Position
Time Limit(sec)
Maximum waiting time, stabilizing time, allowed after premove.
Used for multiple step response test only.
2-Way (round trip)
Selection
The values of the Initial Set Point and the Dest. Set Point deter-
mine the direction of the valve stem movement. When the value
of the Initial Set Point is more than that of the Dest. Set Point,
the valve steps down in one way trip, then steps up at return trip
if 2-way selection specified.
Multi Step Response Test Notice
The graph produced by a multi step response test (Figure 131), does not show actual
time in the time axis because there is loading data time between the two steps.
Figure 131 Step Response Test Graph