Samson 3730 Series Mounting And Operating Instructions page 8

ESD functions
Partial stroke test
The course of the partial stroke test depends
on the parameters listed under Settings in
TROVIS-VIEW 3. Depending on the param-
eter settings, the partial stroke test is con-
ducted either in steps or in a ramp function
of the valve position (see Fig. 2).
After being triggered, the test does not start
until the Settling time before test start (t
elapsed. This waiting period ensures that the
valve has reached the position defined by
the Step start parameter (pos. 2, see Fig. 2)
before the test starts.
Starting from the Step start position (pos. 2),
the valve moves to the defined end position
( Step end parameter, pos. 3). The valve re-
mains in this position for the time defined by
the Delay time after step (t
ing a second step change in the opposite di-
rection from Step end (pos. 3) to Step start
(pos. 2).
8
EB 8388-1 EN
) has
1
) before perform-
2
After the Delay time after step (t
elapsed, the valve is moved back to its initial
position (= Required manual reference vari-
able w , pos. 1)
The Step tolerance limit (range: 0.1 to
10.0 %) sets the permissible tolerance limit
for the step's start and end values.
The Scan rate (range: 0.2 to 30.0 s) defines
the interval at which the measured values
are recorded during the test. If the adjusted
Scan rate matches the Recommended sam-
pling time , the entire step response is avail-
able as a diagram.
Otherwise, only the last 100 measured val-
ues can be analyzed. In this case, the Mea-
sured data storage out of memory parame-
ter is set to "Maintenance alarm", but the
test is not cancelled.
) has
2