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Each of NO and NC contacts supports a capacity of up to 30 VAC/0.5 A or 30 VDC/1 A. For the use of
the unit under a load larger than the capacity, interpose another relay in the connection.
When the load is an inductive load such as a motor or a relay, counter electromotive force may be
generated, which may shorten the life of the contact. Be sure to protect the contact.
Typical contact protection methods are described below.
(a) CR method (applied to AC and DC)
The estimated values of the capacitor C and the resistance R are listed below.
– C: 0.5 to 1 µF, no polarity
– R: 0.5 to 1 Ω for 1 V
– For both C and R, use devices that have a withstand voltage at least twice the voltage used.
(b) Diode method (applied to DC, not applied to AC)
Use a diode that has a reverse withstand voltage 10 times or more the voltage used and a forward
current more than the load current.
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