Overview
The Siemens 42AF35AF is a Class 42 definite purpose contactor engineered for motor control applications requiring robust, long-lasting performance. Rated at 25 amps with a 110/120 VAC 50/60 Hz control coil, this 3-pole device supports up to 7.5 horsepower at 480/600 volt service. The open-type enclosure and dependable design make it ideal for HVAC units, refrigeration systems, pump starters, and factory automation where space and cost efficiency matter.
Key Features
- Weld-resistant silver cadmium oxide contacts ensure long contact life and reduced maintenance intervals.
- Visual contact position indication allows quick status verification without additional instrumentation.
- Compact, space-saving design fits standard DIN and panel mounting with interchangeable mounting footprint.
- Class F coil insulation provides superior thermal stability during extended operation.
- Snap-on auxiliary contact compatibility enables flexible control logic expansion in the field.
- Quick-connect power terminals reduce installation time and retrofit labor costs.
Technical Specifications
- Part Number: 42AF35AF
- Manufacturer: Siemens / Furnas Electric
- Contact Configuration: 3-pole
- Contact Rating: 25 A
- Maximum Voltage: 600 VAC
- Coil Voltage: 110/120 VAC, 50/60 Hz, single-phase
- Horsepower Rating (3-phase): 5 hp @ 240 V; 7.5 hp @ 480 V; 7.5 hp @ 600 V
- Horsepower Rating (1-phase): 2 hp @ 120 V; 3 hp @ 240 V
- Full Load Amperage (FLA): 25 A at all voltages
- Locked Rotor Amperage (LRA): 150 A @ 120 V; 125 A @ 480 V; 100 A @ 600 V
- Enclosure Type: Open (non-reversing)
- Terminal Type: Double quick-connect power terminals; screw terminals for coil
- Operating Temperature Range: –30°C to +70°C (–22°F to +158°F)
- Contact Material: Silver cadmium oxide (weld-resistant)
- Coil Insulation Class: F
- Certifications: UL Listed, CSA Certified
Typical Applications
The 42AF35AF is widely deployed in definite-purpose motor control circuits for:
- HVAC systems: Air conditioning compressors, condenser fan motors, and blower units.
- Refrigeration equipment: Coolers, freezers, and process refrigeration compressors.
- Pump and blower starters: Water pumps, circulation fans, and air handlers.
- Industrial machinery: OEM equipment, welders, and auxiliary motor control panels.
- Commercial controls: Building automation, process starters, and distributed control arrays.
Compatibility & Replacements
The Siemens 42AF35AF maintains pin and footprint compatibility with related Siemens/Furnas contactors in the Class 42 family, including 42BF35AF (30A) and 42CF35AF (40A). For cross-manufacturer applications, the 42AF35AF may serve as a drop-in replacement for comparable definite-purpose contactors from Schneider Electric, Eaton, GE, Allen-Bradley, and ABB, provided voltage, amperage, and auxiliary contact requirements are verified. Replacement coils with screw terminals are standard; quick-connect coils are available separately. Snap-on auxiliary contact modules can be field-added to expand control logic without replacing the main contactor.
