6-6
Electromagnetic Interference
Example 2:
An ac output controls a motor starter,
contacts on the starter control a
motor.
The contacts require RC networks or
Varistors.
The motor requires suppressors
because it is an inductive device.
An inductive device controlled by a
solid state switching device (like the
starter coil in this example) typically
does not require a suppressor.
Example 3:
An ac output controls an interposing
relay, but the circuit can be opened by
dry contacts. Relay contacts control a
solenoid coil.
The contacts require RC networks or
Varistors.
The relay coil requires a suppressor
because it is an inductive device
controlled by dry contacts.
The solenoid coil also requires a
suppressor because it is an inductive
device controlled by dry contacts.
Example 4:
A contact output controls a pilot light
with a built in step-down transformer.
The pilot light requires a suppressor
because its transformer is an
inductive device controlled by a dry
contact.
Example 5:
A contact output controls a relay,
which controls a brake solenoid.
The contacts require RC networks or
Varistors.
Both the relay and the brake solenoid
require suppressors because they
are both inductive devices controlled
by dry contacts.
Examples of Transient Interference Mitigation
digital ac output
solid-state
L1
L2
1MS
L1
switch
1MS
1M
suppressor
L2
suppressor
suppressor
1MS
1MS
L1
digital ac output
solid-state
L1
L2
1CR
switch
suppressor
1CR
1S
suppressor
digital contact output
L1
L2
suppressor
pilot light with built-in
step-down transformer
digital contact output
suppressor
1CR
115V ac
480V ac
1CR
1CR
suppressor
brake solenoid
Содержание Allen-Bradley 1305-AA02A
Страница 1: ...Installation Instructions Wiring and Grounding Guidelines for Pulse Width Modulated PWM AC Drives ...
Страница 4: ...ii Summary of Changes Notes ...
Страница 40: ...2 18 Power Distribution Notes ...
Страница 48: ...3 8 Grounding Notes ...
Страница 68: ...4 20 Practices Notes ...
Страница 78: ...6 8 Electromagnetic Interference Notes ...
Страница 94: ...Glossary 4 UL Underwriters Laboratories ...
Страница 100: ...Index 6 ...
Страница 101: ......