The AF series Contactors from ABB utilise an electronic control coil which is unique and offers some key benefits for difficult applications.
All Contactors rely on the voltage running through a coil to create a magnetic field, when the magnetic field is strong enough it will pull in the Contactor. However this is an analogue process and when the voltage is too low, and the magnetic field is not strong enough to hold the contactor closed, there is a bouncing or chatter effect. This can occur for example when a motor kicks in and there is a dip in the overall system voltage.
The electronic control circuit in the ABB AF Contactors sits between the control input and the coil, so when the input voltage steps outside of the permissible range it will force the contactor to open cleanly. There is no more grey zone where the contactor is bouncing between open and closed states. With the electronic coil technology, the opening and closing sequence is now completely controlled.
How does this benefit the customer?
The main benefit is less wear and tear on the contactor. Most wear on a contactor occurs when the contactor closes and now this is a fast controlled motion. Another benefit is the reduction in the number of product variations required. ABB have been able to reduce the coil options from 45 variations down to just 4 options.
Each of the 4 options have an extremely wide voltage range, can handle both 50 and 60 Hz, and can handle both AC or DC. This is a huge benefit for machine exporters as you don’t need to change your switchgear as often when exporting around the world. Even with the different voltage supplies and frequencies, the same Contactors can be used. With less variations, this also means generally each of the for options are well stocked everywhere in the world, in case of replacement parts.
Coil Codes / Voltage Range
Code 11 20 - 60V DC / 24 – 60V 50/60 Hz AC
Code 12 48 – 130V 50/60 Hz AC, DC
Code 13 100 – 250V 50/60 Hz AC, DC
Code 14 250 – 500V 50/60 Hz AC, DC
Example
AF09 30 10 13
AF-09 CONTACTOR,4kW,100…250V, 1NO AUX
The below video we found really interesting with an analysis of the internals of the AF Contactors , and a demonstration of how the electronic control coil works.