Compliance with EC Directives
Section 3-6
The reverse dielectric strength of the diode must be 10 times the circuit voltage
and the forward current must be at least as high as that of the load. If the circuit
voltage is low enough, as it is for most electronic circuits, then the reverse dielec
-
tric strength of the diode can be as low as 2 to 3 times the circuit voltage.
Inductive load
Power supply
Varistor (AC or DC)
The method uses the fixed voltage characteristics of a varistor to prevent high
voltages from being applied to the contacts. Here, as well, the reset time will be
increase somewhat.
Connect the varistor between the load connections for 24-V and 48-V power
supply voltages and between the contact connections for 100 to 200-V power
supply voltages.
Inductive load
Power supply
Output Surge Current
When connecting an output device having a high surge current (such as an in-
candescent lamp), use one of the following circuit configurations to protect the
Output Unit.
The following circuit lets the load draw a small current (about one third the rated
current) while the output is OFF, significantly reducing the surge current.
OUT
L
+
R
COM
The following circuit reduces the surge current by employing a current-limiting
resistor.
R
OUT
L
+
COM
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OMRON [ OMRON ELECTRONICS LLC ]
