also NO, N.O.
N/O is electrical nomenclature for "Normally Open", this denotes that a relay or other device will not pass current until an electrical signal allows it to or in the case of a button or switch will not pass current until pressed.
"Open" denotes a switch is "off" or not passing current.
N/O is electrical nomenclature for "Normally Open", this denotes that a relay or other device will not pass current until an electrical signal allows it to or in the case of a button or switch will not pass current until pressed.
"Open" denotes a switch is "off" or not passing current.