(Electrical engineering: Circuits, Electrical power, Computing and control) Normally-open switch contacts are in an open state at rest. ▶ normally-closed
⇒ In many applications normally-open valves are required which close when the solenoid pilot is energized. ⇒ Contactors typically have multiple contacts, and those contacts are usually normally-open, so that power to the load is shut off when the coil is de-energized. ⇒ Normally-open switch contacts are in an open state at rest.
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