Finder 6K.13.8.024.4374 – 6K Series Industrial contactors

Why Choose the Finder 6K.13.8.024.4374 74A Industrial Contactor?

The Finder 6K.13.8.024.4374 is a high-performance 74 A three-pole industrial contactor from Finder's Series 6K range, designed for demanding motor control, industrial automation and electrical power-switching applications. Featuring a 24 V AC operating coil, three normally open main contacts (3PST-NO) and robust silver tin oxide (AgSnO2) contact material, this contactor provides dependable electromagnetic switching for appropriately rated industrial loads.

With a rated operational current of 74 A under AC-3 duty at 400 V AC and a corresponding 37 kW three-phase motor power rating, the Finder 6K.13.8.024.4374 is intended for substantially higher-power applications than the smaller 9 A, 12 A and 32 A contactors in the Series 6K family. Its published 130 A AC-1 rating at 690 V AC also makes it suitable for consideration in correctly designed resistive-load switching applications.

The contactor combines a compact 59.8 mm housing width, 35 mm DIN rail mounting, IP20 protection and power terminals suitable for larger industrial conductors. Its three normally open main contacts operate simultaneously, allowing coordinated switching of three-phase electrical supplies. Optional Finder auxiliary contact modules can be used where compatible control feedback or interlocking functions are required.

Key Advantages

• 74 A AC-3 rated operational current at 400 V AC for demanding motor-control applications.
• 37 kW motor power rating at 400 V AC under AC-3 duty.
• 24 V AC operating coil for compatible industrial AC control circuits.
• Three normally open main contacts for coordinated three-phase switching.
• 130 A AC-1 rated operational current at 690 V AC for suitable resistive-load applications.
• AgSnO2 contact material offers robust switching characteristics.
• 59.8 mm-wide housing supports space-efficient high-current panel design.
• 35 mm DIN rail mounting allows integration into industrial control cabinets.
• IP20 protection category for installation within suitable electrical enclosures.
• 4–50 mm² conductor connection range supports appropriately sized power wiring.
• Optional auxiliary contact modules enable additional control and signalling functions.
• 10 kA published short-circuit coordination figure, subject to the specified protective-device arrangement.
• −40 to +60 °C operating temperature range supports a variety of industrial environments.
• Non-latching electromagnetic operation returns the main contacts to their open positions when coil power is removed.

Key Features

• Finder Series 6K industrial power contactor.
• Manufacturer part number: 6K.13.8.024.4374.
• 24 V AC nominal coil voltage.
• AC-operated electromagnetic coil.
• 3PST-NO (3 Form A) main contact configuration.
• Three normally open power contacts.
• 74 A AC-3 operational rating at 400 V AC.
• 37 kW AC-3 motor power rating at 400 V AC.
• 45 kW AC-3 motor power rating at 690 V AC.
• 130 A AC-1 operational rating at 690 V AC.
• Silver tin oxide (AgSnO2) main contacts.
• 35 mm DIN rail mounting according to EN 60715.
• 59.8 mm housing width.
• 110 mm housing height.
• Approximately 92 mm housing depth.
• IP20 protection category.
• 4–50 mm² power-conductor connection range.
• Optional 1 NO or 1 NC auxiliary contact modules.
• Auxiliary module AC-15 rating: 2 A at 400 V AC, for the specified compatible modules.
• Non-latching electromagnetic switching mechanism.

74A Three-Phase Motor Switching with 24 V AC Contactor Control

The Finder 6K.13.8.024.4374 uses a 24 V AC electromagnetic coil to operate three normally open main power contacts. When the coil is energised within its specified operating range, all three main contacts close, allowing power to flow to the connected load. When the coil supply is removed, the non-latching mechanism releases and the main contacts return to their normally open positions.

The contactor's 74 A AC-3 rating at 400 V AC makes it particularly relevant to three-phase motor-control applications. AC-3 is the utilisation category commonly associated with starting squirrel-cage motors and switching them off during normal running conditions. The corresponding 37 kW motor rating provides a useful selection reference for compatible equipment.

For higher-voltage motor systems, the published 45 kW motor rating at 690 V AC provides an additional application reference. Engineers must select the contactor according to the motor's actual nameplate current, starting characteristics, switching frequency and the applicable utilisation category rather than relying on motor power alone.

The 130 A AC-1 rating at 690 V AC applies to appropriately rated resistive or slightly inductive loads. It must not be interpreted as a 130 A AC-3 motor-switching rating. Motor starting currents and switching conditions are more demanding, which is why the AC-3 rating is lower than the AC-1 rating.

The 24 V AC coil is designed for compatible AC control systems. It is not interchangeable with a 24 V DC coil, even though the nominal voltage number is the same. The control transformer, switching device and protective components must be selected for the coil's actual voltage, frequency and consumption characteristics.

Unlike smaller Series 6K models that may include a fourth contact within the contactor body, the 6K.13.8.024.4374 has three main normally open contacts. Where electrical interlocking, control feedback or signalling is needed, compatible Finder 06K.11 normally open or 06K.12 normally closed auxiliary contact modules can be considered. These auxiliary contacts have their own ratings and must not be used as additional high-current motor power poles.

The contactor's AgSnO2 main contacts, substantial power-terminal capacity and DIN rail-mounted housing make it suitable for industrial control-panel construction. Appropriate overload protection, short-circuit protection, conductor sizing, enclosure ventilation and electrical clearances are essential for safe operation, particularly at the higher currents associated with this 74 A model.

Typical Applications

• Three-phase motor starters for appropriately rated industrial motors.
• High-power industrial motor-control panels.
• Industrial pumps and large pumping systems.
• Industrial compressors and compressed-air equipment.
• Large ventilation fans and air-handling machinery.
• Conveyor systems and heavy material-handling equipment.
• Industrial processing and manufacturing machinery.
• Electrical power distribution and load-switching assemblies.
• Heating and industrial process-control equipment.
• Industrial automation and OEM machinery panels.
• Motor-control centres and DIN rail-mounted electrical cabinets.
• Applications requiring 24 V AC control of higher-current three-phase loads.