ABB HENF331270R0001 O4LCA Transmitter Controller Transducer

Communication Protocols:

Contactors are electromagnetically operated switches. The functional principle can be described as follows: 

when control power flows through the magnet coil of a contactor, the resulting magnetic field attracts the 

mechanical contact carrier. By interruption of the coil control circuit, the mechanical contact carrier returns to the starting position.

ABB contactors are provided in either three or four power pole configurations with a variety of accessories, 

including auxiliary contacts, easy connecting links (between products), interlocks, and bus bars. 

Contactors are primarily used for controlling single and three-phase motors and switching power circuits.

The ABB contactors belong to the class of air-break contactors. If coil power is removed, an arc 

is created as the contacts open. Air-break contactors extinguish the arc by having a sufficient distance separating the contacts.

The electronic system within the AF contactor continuously monitors the current and 

voltage applied to the coil. The contactor is safely operated in an always optimized condition and hum-free.

With conventional contactor technology, different contactors are needed for different network voltages. 

 Thanks to the wide operating range of the AF contactor, it can operate equally well in Europe as in Asia or North America. 

The core coil of the AF contactor range covers 100-250 V AC / DC, 50 / 60 Hz.

The use of the logic control signals also requires a steady voltage on terminals A1 and A2 within the operational limits. 

The minimum pulse length for opening and closing is 7 msec. The function of the logic control signals will no longer 

be guaranteed when the logic on A1 and A2 is removed. The logic control signals operate with 24 V DC and consist 

of two control signals (ON and OFF_N) and a common reference (COM). To close the contactor, it is sufficient to 

have a control pulse at ON and to open its removal of voltage from OFF_N.