NSD Varlimit VS-212DN, User Manual

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8-2
(5) The minimum permissible width of ON and OFF zones is according to the position detection spacing
of the ABSOCODER sensor being used.
Position data sampling occurs every 2 ms at the VS-212DN.
The detected position is then compared with the designated ON/OFF settings, with limit switch
output being executed accordingly.
Therefore, if the machine exceeds a given permissible speed, position detection at each of the
minimum scale length units will become impossible, and the external output of ON and OFF signals
as designated will also be impossible.
In such cases, the width of the ON and OFF signal zones must be increased.
The following formula is used to calculate the permissible speed:
Permissible speed = Minimum scale length unit/ Sampling time
×
Width of signal zone/ Minimum
scale length unit
Example)
When ‘minimum scale length unit’ is 0.01 mm, and ‘width of signal zone’ is 0.1 mm:
Permissible speed = 0.01 mm/ 2 ms
×
0.1 mm/ 0.01 mm = 0.1/2
×
100 = 50 mm/s
(6) Up to 10 ON/OFF data settings can be designated for each VS-212DN channel. This is referred to
as the ‘multi-dog setting function’.