Normally Closed Switch In Plc. Click the toggle button to switch to the instruction tool bar. Unlike open contacts with normally closed contacts signal will interrupt a contact or turn a relay off.
If it is a relay then it is not energized. In the default state inactivated of a normally closed actuator the input bit is 1. When you activate a normally closed actuator the input bit is 0.
I 1 9 is a normally open push button and i 1 10 is a.
If it is a switch then it is off. But those standards are quite expensive if you are just looking for the symbols used in ladder diagrams. Closed current flow. All the symbols can be found in the standard defining ladder diagram programming.
