ZD340_07d_e.doc / Apr-17
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4.9. Monitor for Slip, Torsion, Skew Position, Shaft Fracture:
F07.062 = 9
This counter mode is a special version of the Differential Counter described previously. As a
major difference, in this mode all four presets and outputs (K1 – K4) refer exclusively to the
differential count, and also a programmable slip function has been added.
Before forming the difference, each of the two encoder inputs is scaled individually according
to the setting of the impulse scaling factor. If applicable, the differential result can once more
be scaled to engineering units with use of the final scaling operands.
Since presets and outputs can be set to positive and negative values as well, it is also possible
to use the unit for simple synchronous control purpose of two drives, by temporary accelerating
or breaking one of the drives when lagging or leading the other. Typical examples are large
rolling gates or lifting ramps or gantry cranes, driven by several independent motors.
Some applications (e.g. with couplings) can accept (or even may require) a certain slip.
For slip control with adjustable slip parameters, an automatic timer function can be
programmed to reset the counters periodically.
Multi-purpose parameter F04.030 is used to set the reset cycle in seconds (00.0 = no automatic
reset, 99.9 = reset every 99.9 seconds)
Since with slip applications, where the automatic reset function is switched on, the real time
display of the counter may be very confusing, multi-purpose parameter F04.031 works to reduce
the update rate of the display
(0 = real-time display, 1 = 8 msec., 2 = 16 msec., 3 = 32 msec., 4 = 64 msec. etc.)
Besides the differential count, the display can be scrolled to indicate also the following values:
Display
L1 (red)
L2 (yellow)
1
Differential count (encoder1 – encoder2)
--
--
2
Minimum difference (since last reset)
blinking fast
--
3
Maximum difference (since last reset)
--
blinking fast
4
Encoder 1 only
blinking slow
--
5
Encoder 2 only
--
blinking slow
1 2 3 4 5 6
Encoder 1
Encoder 2
Motor
Encoder
Encoder
Alert 1
Alert 4
Control of Shaft and Gearbox Fracture
