Switch Types and Common Terminology National Instruments
Form C Contact. Form c contact assembly has three terminals. It is hermetically sealed with 3 leads:
One normally open and one normally closed. 2 form c (2 co) signal relay contact switching voltage (max)(vac): There is a common electrical connection between a contact of each pair that results in only three connection terminals. They can be part of any type of a relay or auxiliary switch. Web a single form c contact isn’t much good unless you are trying to design a system whose pl only requires pl a or pl b, but adding a second contact to this device adds the possibility of monitoring the relay. This is also called a “changeover” device because the common contact changes from the normally closed position to the normally open position when the coil is energized in a relay or a magnetic field is nearby in a reed switch. A form c contact is also called spdt. Form c contact assembly has three terminals. This type of contact controls two circuits: Web form c is one normally open contact and one normally closed contact with a common terminal between them.
Web a form c reed switch is essentially a single pole double throw reed switch. Form x = no with both terminals disconnected when off. 2 form c (2 co) signal relay contact switching voltage (max)(vac): Form c contact assembly has three terminals. Web a single form c contact isn’t much good unless you are trying to design a system whose pl only requires pl a or pl b, but adding a second contact to this device adds the possibility of monitoring the relay. Web a form c reed switch is essentially a single pole double throw reed switch. This is caused by the magnetic field produced by a coil or the magnetic field from a magnet. Form y = nc with both terminals disconnected when off. This type of contact controls two circuits: These contacts have a common terminal. When operated the common contact will swing from the normally closed contact to the normally open contact.
