NO, NC contacts: the definition is based on their state when no power is applied; normally open and normally closed contacts refer to their state in that condition. However, many people mistakenly think it relates to the state when power is applied...
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Contacts that are in a closed state under normal conditions (with no power applied and no current flowing through) are called normally closed contacts. Normally open – NO (normal open): It is in an off state under normal circumstances, that is, it is disconnected when the coil is not powered. Normal closed – NC (normal close): It is usually in a closed state, that is, it remains closed when the coil is not powered.
Normally open and normally closed states certainly correspond to a state with no power supply; this is usually indicated, and even if it isn’t, it can be determined using a meter to see whether it’s in the open state