Switch Types and Common Terminology National Instruments
Form C Contact. Web form c is one normally open contact and one normally closed contact with a common terminal between them. 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 a “ form c ” would have 3 leads and would have 1 normally open and 1 normally closed circuit. A form c isolated relay would have three terminals. Form c contact assembly has three terminals. One normally open and one normally closed. 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. It is hermetically sealed with 3 leads: 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. Form y = nc with both terminals disconnected when off. Form x = no with both terminals disconnected when off. When operated the common contact will swing from the normally closed contact to the normally open contact.
Web a “ form c ” would have 3 leads and would have 1 normally open and 1 normally closed circuit. This is caused by the magnetic field produced by a coil or the magnetic field from a magnet. 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. It is hermetically sealed with 3 leads: 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 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. Web a “ form c ” would have 3 leads and would have 1 normally open and 1 normally closed circuit. A form c isolated relay would have three terminals. Web a dry contact is one that is a hard contact such as a relay or switch (as opposed to a triac or transistor). They can be part of any type of a relay or auxiliary switch.
