Line Filtering Configurations For Controls
Figure
3
-
These three diagrams show you filter configurations for removing input power
noise. Choose the one best suited for your system.
For very dirty or
critical
applications
-
use a microcomputer-regulated power supply or
Uninterruptable
Power Supply (U.P.S.)
Don’t fasten common mode line filters or filters with
metal cases to metal that is at ground potential. This prevents ground loops
and maintains filter effectiveness.
Differential
Mode
Filter
Wiring
Ll
D.M.
Line Filter
.
NOTE: Keep filters
12
inches or less
from the control.
Minimize
the line
distance where
nolse can be
re-
introduced to
control.

Control

Common
Mode
Filter
Wiring
2
NOTE:
To
prevent
ground loops do not
fasten common
mode line
filters
or
filters
with metal
cases to metal that
is at ground
poten-
tlal.
Doing so will
reduce filter effec-
tiveness.
Figure
5
-
Combination
Differential/
Common Mode Filter
Wiring
C.M. Line Filter

Control

I
Ground
Control
10 WATLOW
Series
980/985
User's
Manual
Install and Wire, Chapter 2