CONTREX ML-Drive - Manual (Page 77)

3 - 43
Performance Monitoring
Performance Monitor Parameters monitor the performance of the ML-Drive and your
system. Figure 3-2 is a block diagram of the internal control structure of the ML-Drive
and the Performance Monitor Parameters.
Lead
Frequency
(MP-41)
Feedback
Frequency
(MP-43)
Active
Scaling
(MP-50)
Master
Follower
Feedback
Scaling Tach
(MP-40)
Scaled
Reference
(MP-45)
Accel /
Decel
Ramped
Reference
(MP-46)
Deviation
(MP-44)
Trim
Output
(MP-48)
Drive Output
(MP-47)
PIDF Output
(MP-49)
Feedforward
PID Compensation
Routine
+
+
–
+
+
+
Figure 3-2 ML-Drive Internal Structure
MP-40 TACH
Tach (MP-40) is the feedback displayed in scaled Engineering Units or RPM. In the
Master mode, Tach (MP-40) will display the feedback in Master Engineering Units
(CP-20). In the Follower mode, Tach (MP-40) will display either Master Engineering
Units or the feedback to Lead ratio in Follower Engineering Units (CP-21), depending
on the value in Display Mode Follower (CP-64). In Jog or the Direct mode, Tach (MP-
40) will display the feedback in RPMs. The feedback is read by the ML-Drive every ten
milliseconds. The readings are summed, then averaged for one second before the
Tach is displayed.
MP-44 DEVIATION (ERROR)
Deviation (MP-44) displays the difference between the Ramped Reference (MP-46) and
the Feedback Frequency (MP-43) measured in units of hertz (pulses per second).
Deviation (MP-44) is not averaged or filtered; it is the ten millisecond frequency
calculation prior to the display update.