• Avoid using contact protection circuits like the following. Although they are highly effective in reducing the
arc at current cutoff, a charge current flows into the capacitor when the contact turns on or off, which leads
to the risk of contact welding. A DC inductive load, generally considered to be more difficult to open and
close than a resistive load, can achieve the same performance of a resistive load in an appropriate
configuration of the protection circuit.
Inductive
load
• Install the protection circuit near the load or contact (module). A long distance between them may inhibit the
effect of the protection circuit. As a guide, install it at a distance of no more than 50cm.
Inductive
load
6 INSTALLATION AND WIRING
6.1 Before Using the I/O Modules
6
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