Omron CS1W-MC221 -, Operation Manual

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372
Stopping Section 6-21
For example, when controlling a turntable, suppose that the present position
update range is 0
°
to 360
°
. If the gear ratio is 7/99 and the encoder resolution
is 1,000 pulses, the following error will be accumulated with each 360-degree
turn.
Gear ratio (degrees/pulse)
= 7 x 360
°
/ (99 x 1,000 pulses)
= 2,520 / 99,000 pulses
360
°
x 99,000 / 2,520 = 14,142.857 pulses
Thus an error of 0.857 pulses will be accumulated with each turn.
Restrictions on Unlimited Axis Operation for Servomotors (U Series or
W Series) with Absolute Encoders
When using a U-series Servomotor with an absolute encoder, the denomina-
tor of the gear ratio for the gear must be a factor of 10,000.
For example, gear ratios of 1/2, 1/4, 1/5, 1/20, 1/25, 1/40, 1/50, and 1/100 can
be selected. The servolocked present value must be regenerated when the
gear ratio is selected. Present value regeneration is performed according to
the following calculations.
A: Binary counter present value
A
÷
No. of pulses per motor revolution = Quotient B; Remainder C
B
÷
Gear ratio = Quotient D; Remainder E
Convert the result of {E
×
No. of pulses per motor revo C} according
to the present value unit used and transfer it to the MC Unit.
When using a W-series Servomotor, by setting the absolute encoder multi-
turn limit setting (Pn205), a gear with a different gear ratio (1/n) from the ones
above can be used. If the absolute encoder multi-turn limit setting (Pn205) is
set to {gear ratio
÷
1}, because the servolocked present value is equal to the
present value on the turntable, the present value does not have to be regener-
ated.
6-21 Stopping
The MC Unit has various ways of stopping axis operation, as shown in the fol-
lowing table.
Method Activation timing Remarks
Manual/Automatic Bit Upon input. Each axis is decelerated to a stop upon input.
During interpolation operations, axis operation is stopped after
moving from the interpolation locus.
Cycle Start OFF When G-language program
interpretation is started. This bit is checked when interpretation of the G-language is
started (at the beginning of a block). If it is OFF, the
G-language program is not executed.
In In-position Check OFF Mode or Pass Mode, however, this bit
is not checked until the next block.
Pause ON Upon input. Each axis is decelerated to a stop upon input.
During interpolation, axis operation is stopped at the
interpolation locus.
Forced Block End Upon input. Each axis is decelerated to a stop upon input.
During interpolation operations, axis operation is stopped after
moving from the interpolation locus.
Optional End Upon input. Each axis is decelerated to a stop upon input.
During interpolation operations, axis operation is stopped after
moving from the interpolation locus.