Operation
4-2
Capacitive loads
The initial surge current from a
capacitive reactive load must be limited. Figure 4-2
shows circuits that can be used to limit current surges.
To protect the relay, limit current to 1A. Also consider
the load when determining the current surge limit.
Load
R
H
L
Out
IN
H
L
A. Resistor Clamped (AC or DC Voltages)
H
L
Out
IN
H
L
D
B. Diode Clamped (DC Voltages)
H
L
Out
IN
H
L
C. Zener Clamped (AC Voltages)
Load
R
H
L
Out
IN
H
L
C
D. Resistor-Capacitor Clamped (AC Voltages)
Load
Zener
Diode
Load
+
1A
FUSE
7013
7013
1A
FUSE
1A
FUSE
7013
Diode
Zener
Diode
Diode
1A
FUSE
7013
Figure 4-1
Limiting inductive reaction voltage
Load
R
Out
H
L
IN
H
L
A. Resistor Limited R = I Limit
Load
Out
H
L
IN
H
L
Thermistor*
(Rs)
High resistance when cold.
Low resistance when hot.
Fast thermal recovery.
B. Thermistor Limited Rs = I Limit
*
7013
1A
FUSE
V
1A
FUSE
7013
V
Figure 4-2
Limiting capacitive reaction current
Summary of Contents for 7013-S
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