
2. HARDWARE
B–63465EN/01
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Generally, noise is generated by electrostatic coupling, electromagnetic
induction, and ground looping, and introduced to the Digital Servo
Adapter. However, it is difficult to measure the level and frequency of
noise quantitatively, and noise has many uncertain factors. It is important
to prevent both noise from being generated and generated noise from
being introduced into the Digital Servo Adapter. This precaution
improves the stability of the Digital Servo Adapter machine system.
The Digital Servo Adapter component units are often installed close to the
parts generating noise in the power magnetics cabinet. Possible noise
sources into the Digital Servo Adapter are capacitive coupling,
electromagnetic induction, and ground loops.
When designing the power magnetics cabinet, guard against noise in the
machine as described in the following section.
The cables used for the machine are classified as listed in the following table:
Process the cables in each group as described in the action column.
Group Signal line Action
Primary AC power line
Bind the cables in group A
Secondary AC power line
separately (Note 1) from groups B
A
AC/DC power lines (containing the
power lines for the servo and
spindle motors)
and C, or cover group A with an
electromagnetic shield (Note 2).
See Section 2.11.4 and connect
AC/DC solenoid
spark killers or diodes with the
solenoid and relay.
AC/DC relay
solenoid and relay.
DC solenoid (24VDC)
Connect diodes with DC solenoid
and relay.
Bind the cables in group B
B
DC relay (24VDC)
separately from group A, or cover
group B with an electromagnetic
shield.
Separate group B as far from
DC power line
Separate group B as far from
Group C as possible.
It is more desirable to cover group
B with the shield.
Feedback cable
Bind the cables in group C
separately from group A, or cover
RS–232–C interface cable
separately from group A, or cover
group C with an electromagnetic
shield.
C
Cable for the battery
shield.
Separate group C as far from
Other cables to be covered with
the shield
Group B as possible.
Be sure to perform shield
processing in Section 2.11.5.
NOTE
1 The groups must be 10 cm or more apart from one another
when binding the cables in each group.
2 The electromagnetic shield refers to shielding between
groups with grounded steel plates.
2.11
ACTION AGAINST
NOISE
2.11.1
Separating Signal
Lines