Switch Types and Common Terminology National Instruments
Form C Contact. It is hermetically sealed with 3 leads: Web a form c reed switch is essentially a single pole double throw reed switch.
It is hermetically sealed with 3 leads: A form c contact is also called spdt. These contacts have a common terminal. Web a “ form c ” would have 3 leads and would have 1 normally open and 1 normally closed circuit. They can be part of any type of a relay or auxiliary switch. Web form c is one normally open contact and one normally closed contact with a common terminal between them. Form x = no with both terminals disconnected when off. 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 type of contact controls two circuits: Web form c contacts (change over or transfer contacts) are composed of a normally closed contact pair and a normally open contact pair that are operated by the same device;
One normally open and one normally closed. When operated the common contact will swing from the normally closed contact to the normally open contact. This is caused by the magnetic field produced by a coil or the magnetic field from a magnet. They can be part of any type of a relay or auxiliary switch. Form c contact assembly has three terminals. Form c is a combination. 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. Web form c contacts (change over or transfer contacts) are composed of a normally closed contact pair and a normally open contact pair that are operated by the same device; Web a form c reed switch is essentially a single pole double throw reed switch. A form c isolated relay would have three terminals. It is hermetically sealed with 3 leads:
