MPH-02, MPB-02, MPD-02
Extended Drive Functions
9-5
DOK-INDRV*-MP*-02VRS**-FK01-EN-P
With each measuring event a status information is generated and
incremented for each probe, depending on the polarity of the respective
measured value trigger. This is particularly advantageous for continuous
measurement in order to detect new measuring events. This status
information is stored in the corresponding parameter:
•
S-0-0409, Probe 1 positive latched
•
S-0-0410, Probe 1 negative latched
•
S-0-0411, Probe 2 positive latched
•
S-0-0412, Probe 2 negative latched
Note:
By integration of the probe status information and the
measured values or measured value differences in the cyclic
data of the master communication the current measuring
processes are signaled to the control master and the
corresponding measured values are supplied.
The controller generates the actual position values, depending on the
available hardware and firmware as well as the performance setting in
P-0-0556, Control word of axis controller
, on a fixed time base:
•
500
µ
s for basic performance
•
250
µ
s for advanced performance
The probe signal edge (trigger), however, is detected by the "rapid" digital
input on a relatively short time base of 4.0
µ
s. The actual position value
corresponding to the time of the signal edge is determined by linear
interpolation between the last and the next actual position value
generated by the controller.
A restart of the single measurement or the continuous measurement is
triggered by resetting (1
→
0) and repeated setting (0
→
1) of the
parameters for the probe enable:
•
S-0-0405, Probe 1 enable
•
S-0-0406, Probe 2 enable
When doing this, the following data are cleared:
•
the measured values (S-0-0130, S-0-0131 or S-0-0132, S-0-0133),
•
the measured value differences (P-0-0202 or P-0-0203),
•
the information of the measured value trigger status (S-0-0409/S-0-
0410 or S-0-0411/S-0-0412) and
•
the
counter
P-0-0224, Probe, number of marker failures
(see below)
The position range of an axis or shaft within which probe signal edges
cause measured values to be detected can be limited. In the case of
limitation, measured value trigger signals are only expected within
position limits that can be set, this range is therefore called "expectation
window". The measured value detection limited to the "expectation
window" is activated in parameter
P-0-0226, Probe, extended control
word
.
Detecting marker failures with activated "expectation window":
•
If the actual position value is outside of the "expectation window",
probe signal edges do not cause measured values to be detected!
If there hasn’t any "marker" causing a measured value trigger been
detected after completely passing through the "expectation window"
(both position limits exceeded), this status can be stored and displayed
in parameter
P-0-0224, Probe, number of marker failures
. To do this
it is necessary to activate the "marker failure monitor" in parameter
P-0-0226. In case of recurrence the value of P-0-0224 is incremented.
Measured Value Status
Precision
Restart or Deactivation of
Measured Value Detection
Using the "Expectation Window"
Courtesy
of
CMA/Flodyne/Hydradyne
▪
Motion
Control
▪
Hydraulic
▪
Pneumatic
▪
Electrical
▪
Mechanical
▪
(800)
426-5480
▪
www.cmafh.com
