Thermal Magnetic overload protection
The A1A020TW-2 is a Thermal Magnetic type contactor from ABB's A1A series, rated for the 20-400 A range. The thermal element provides inverse-time overload protection; the magnetic element handles short-circuit trip. This dual-action design means the contactor serves both as a switching device and as overload protection in a single unit, reducing panel wiring and component count.
As a contactor in the A1A series, the A1A020TW-2 mounts on a DIN rail in a standard control panel. The 20-400 A range covers motor loads from fractional horsepower up to medium-duty pumps and conveyors. The Thermal Magnetic trip unit eliminates the need for a separate overload relay in many circuits, saving DIN rail space and reducing wiring terminations.