Finder 77.F3.8.230.8671 – 77 Series Modular solid state relays

Why Choose the Finder 77.F3.8.230.8671 Three-Phase Solid State Relay?

The Finder 77.F3.8.230.8671 is an industrial 80 A three-phase solid state relay (SSR) designed for reliable, contactless switching of high-current AC loads. Part of the Finder 77 Series, this relay combines semiconductor switching technology with a robust hockey-puck-style housing, making it suitable for industrial heating, process control and automated machinery applications.

Featuring a 90–280 V AC control input and a 24–660 V AC load switching range, the Finder 77.F3.8.230.8671 enables compatible AC control systems to operate three-phase electrical equipment. Its three normally open semiconductor outputs (3PST-NO) provide an 80 A rated switching capability when used with appropriate heat-sink selection and thermal management.

The relay incorporates random turn-on switching, allowing the semiconductor outputs to activate without deliberately waiting for an AC voltage zero crossing. Its silent operation, contactor-style screw terminals and panel or heat-sink mounting arrangement make it a practical choice for demanding industrial installations requiring frequent switching without mechanical contact wear.

Key Advantages

• 80 A rated output current for appropriately rated three-phase AC loads.
• Three normally open semiconductor outputs for three-phase switching applications.
• 90–280 V AC control input for integration with compatible industrial control circuits.
• 24–660 V AC switching range for a broad selection of AC equipment.
• 600 V AC rated output voltage for suitable industrial electrical systems.
• Random turn-on switching for rapid response to control signals.
• Silent semiconductor operation without mechanical switching noise.
• Spark-free and bounce-free switching during normal electronic operation.
• High switching endurance without mechanical output contact wear.
• Contactor-style terminal arrangement for convenient three-phase wiring.
• Panel or heat-sink mounting for flexible installation and thermal management.
• 47–400 Hz operating frequency range for compatible AC applications.
• IP20 protection rating for installation within suitable electrical enclosures.

Key Features

• Finder 77 Series industrial solid state relay.
• Model: 77.F3.8.230.8671.
• Three-phase AC load switching.
• Output configuration: 3 normally open semiconductor outputs (3PST-NO).
• Rated output current: 80 A.
• Rated output voltage: 600 V AC.
• Load switching voltage range: 24–660 V AC.
• Nominal control voltage: 230 V AC.
• Control input voltage range: 90–280 V AC.
• Switching characteristic: Random turn-on.
• Operating frequency: 47–400 Hz.
• Ambient operating temperature: −30 to +80 °C.
• Off-state leakage current: 10 mA.
• Hockey-puck-style housing for industrial mounting.
• Contactor-style terminals with input and output connections on adjacent sides.
• Screw terminal connections.
• Panel or heat-sink mounting.
• Housing dimensions: 105 × 78 × 36.5 mm.
• Protection classification: IP20.
• Approvals and markings: CE, UKCA, EAC and cURus.

High-Current Three-Phase Random Turn-On Switching for Industrial Control

The Finder 77.F3.8.230.8671 uses electronic semiconductor switching elements instead of conventional mechanical contacts. When a suitable 90–280 V AC control signal is applied, the relay activates its three semiconductor output paths to switch the connected three-phase AC load. Its random turn-on characteristic enables switching in response to the control signal without deliberately delaying activation until an AC voltage zero crossing.

This operating principle supports frequent, silent switching in industrial heating and appropriately rated machinery control applications. The relay's 80 A output rating requires suitable heat-sink selection and thermal management. Installation must account for ambient temperature, load characteristics, wiring, ventilation and protective devices. Because semiconductor outputs can exhibit off-state leakage current, the relay must not be used as a substitute for a mechanical electrical isolator.

Typical Applications

• Three-phase industrial heating equipment.
• Industrial ovens, furnaces and drying systems.
• High-current resistive heating loads.
• Industrial process and temperature control systems.
• Automated manufacturing and production machinery.
• Industrial motor control with appropriately rated loads.
• Packaging and material handling equipment.
• Three-phase electrical control panels.
• OEM machinery requiring frequent semiconductor switching.
• Industrial applications requiring silent, contactless AC load control.