Switch Types and Common Terminology National Instruments
Form C Contact. This is caused by the magnetic field produced by a coil or the magnetic field from a magnet. Form c contact assembly has three terminals.
Form c is a combination. Form y = nc with both terminals disconnected when off. 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. 2 form c (2 co) signal relay contact switching voltage (max)(vac): Form x = no with both terminals disconnected when off. Web a dry contact is one that is a hard contact such as a relay or switch (as opposed to a triac or transistor). A form c isolated relay would have three terminals. 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.
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; When operated the common contact will swing from the normally closed contact to the normally open contact. Form c contact assembly has three terminals. Web a form c reed switch is essentially a single pole double throw reed switch. One normally open and one normally closed. 2 form c (2 co) signal relay contact switching voltage (max)(vac): They can be part of any type of a relay or auxiliary switch. A form c isolated relay would have three terminals. A form c contact is also called spdt. This is caused by the magnetic field produced by a coil or the magnetic field from a magnet. Form x = no with both terminals disconnected when off.
