Omron trajexia CJ1W-MCH72, Operation Manual

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How-to’s Section 5-1
307
The delay in the capture in the Sigma-II Servo Driver is about 3
µ
s. As the
encoder information is refreshed every 62.5
µ
s, it is necessary to make
interpolation to obtain the right captured position value (see the picture). Since
the motor speed cannot change much during 62.5
µ
s, the resulting accuracy is
very high.
The delays in transmission of the information are:
• Delay in triggering the registration: 0.625 ms to 4 ms.
• Delay in receiving the registration: 3.5 ms.
• Delay in capturing the registration: 3
µ
s.
It is also possible to use the encoder Z-mark to register an axis position. This
is also done with the argument of the
REGIST command.
5-1-6-3 Registration in the Junma Servo Driver
Registration in the Junma Servo Driver is the same as registration in the
Sigma-II Servo Driver, with one difference: There is only one physical input
and one logical latch too, so no settings of Servo Driver parameters are
necessary. The physical input is associated to logical latch EXT1, and only the
rising signal edge can be used for registration.
5-1-6-4 Registration in the G-Series Servo Driver
Registration in the G-Series Servo Driver is the same as registration in the
Sigma-II Servo Driver, with one difference: There are three physical inputs but
only one can be activated at a time. The physical input is associated to logical
latch EXT1, EXT2 and EXT3, but the corresponding locations on the CN1
connector are fixed, so no settings of Servo parameters are necessary. Only
the rising signal edge can be used for registration.
In contrast with all other types Servo Drivers, the G-series Servo Drivers do
not support executing registration while it is in base-block state. The
registration can be executed on G-Series Servo Drivers only when
WDOG is
set to ON. If registration is required when the G-Series Servo Driver is in base-
block state, this workaround can be used: put the G-Series Servo Driver in
torque mode with zero torque by executing:
• ATYPE=42
• T_REF=0
and then perform registration.
5-1-6-5 Registration in the Encoder Interface
The CJ1W-MCH72 has three physical registration inputs (two registration
inputs, see section 2-1-1, and encoder Z-mark input, see section 2-2-2), and
two latch circuits, which can be used independently. Therefore two
independent registration inputs can be used at the same time. For more
information on how to use both registration inputs of the CJ1W-MCH72 at the
same time, refer to sections 4-2-152, 4-2-153, 4-2-198, 4-2-199 and 4-2-200.
The delay in the capture is 0.5
µ
s. Because the encoder position is read
continuously from the line-drive encoder input, interpolation is not necessary.
The delay for the transmission of the captured information is just one
SERVO_PERIOD cycle.