Finder 77.F1.8.230.8650 – 77 Series Modular solid state relays

Why Choose the Finder 77.F1.8.230.8650 Solid State Relay?

The Finder 77.F1.8.230.8650 is a high-capacity 80 A single-phase solid state relay (SSR) designed for reliable, silent and contactless switching of industrial AC electrical loads. Part of the Finder Series 77, this industrial switching device combines a nominal 230 V AC control input, a 24–660 V AC output switching range and zero-crossing technology in a robust hockey puck-style housing.

Featuring a 90–280 V AC control voltage range and a single normally open equivalent output, the Finder 77.F1.8.230.8650 is particularly suitable for industrial heating systems, electrical process equipment, lighting control and automated AC load switching. Its 80 A rated output current provides substantial switching capacity when installed with appropriate thermal management.

The relay uses semiconductor switching technology instead of moving mechanical contacts. This delivers silent operation, fast switching and freedom from mechanical contact bounce. Its zero-crossing switching characteristic helps minimise electrical disturbances when energising suitable AC loads, making it especially useful for resistive heating and other compatible industrial applications.

Designed for panel or heatsink mounting, the Finder 77.F1.8.230.8650 features a hockey puck-style housing, screw terminal connections and protective folding terminal covers. Its relay-style terminal arrangement positions the control and load connections on opposite sides, supporting practical integration into industrial electrical control panels.

Key Advantages

• 80 A single-phase solid state relay for high-current industrial AC switching.
• 230 V AC nominal control input for compatible mains-voltage control circuits.
• 90–280 V AC control voltage range for flexible industrial applications.
• 24–660 V AC output switching range for a wide variety of AC electrical loads.
• Zero-crossing switching technology helps reduce switching transients in suitable applications.
• 800 A maximum peak current for 10 ms under specified conditions.
• Contactless semiconductor operation eliminates mechanical contact wear and contact bounce.
• Silent switching for industrial machinery and building services installations.
• Single normally open equivalent output for straightforward AC load control.
• Hockey puck-style housing with folding screw terminal covers.
• Relay-style terminal arrangement with input and output connections on opposite sides.
• Panel or heatsink mounting for industrial electrical cabinets.
• 47–400 Hz operating frequency range for compatible AC systems.
• −30 to +80 °C ambient temperature range, subject to current derating and thermal requirements.
• IP20 protection rating for suitably protected electrical installations.
• Suitable for industrial heaters, process equipment, lighting circuits and automated AC switching.

Key Features

• Finder Series 77 industrial solid state relay.
• Single-phase AC output switching.
• Output configuration: 1 normally open equivalent (SPST-NO / 1 Form A).
• Rated output current: 80 A.
• Output switching voltage: 24–660 V AC.
• Nominal control voltage: 230 V AC.
• Control voltage range: 90–280 V AC.
• Control input type: AC.
• Switching characteristic: Zero crossing.
• Maximum peak current: 800 A for 10 ms.
• Output operating frequency: 47–400 Hz.
• Hockey puck-style industrial housing.
• Folding screw terminal covers.
• Relay-style input and output terminal arrangement.
• Panel or heatsink mounting.
• Screw terminal connections.
• Operating ambient temperature: −30 to +80 °C.
• Protection rating: IP20.
• Silent, contactless switching without moving power contacts.

Advanced 80 A Zero-Crossing Switching for Industrial AC Loads

The Finder 77.F1.8.230.8650 is designed to switch high-current single-phase AC loads electronically using a compatible AC control signal. When the control voltage is applied within its specified 90–280 V AC input range, the relay activates its semiconductor output close to the next AC voltage zero crossing.

Zero-crossing switching means the relay begins conducting when the instantaneous AC voltage is close to zero. This helps reduce switching disturbances and electromagnetic interference in suitable applications, particularly when controlling resistive heating elements and other compatible electrical loads.

For industrial heating applications, zero-crossing switching can be especially useful where loads are repeatedly switched on and off by a temperature controller. It allows electrical heating equipment to be controlled without the audible clicking and mechanical contact wear associated with conventional electromechanical relays.

The Finder 77.F1.8.230.8650 offers a substantial 80 A rated output current and a 24–660 V AC switching range. This makes it suitable for appropriately rated industrial heating systems, process machinery and high-current AC switching applications.

The specified 800 A maximum peak current for 10 ms provides a short-duration surge withstand capability. This figure must not be confused with the relay's continuous operating current. Loads with significant inrush current require careful assessment against the manufacturer's surge ratings and operating limits.

Because the relay uses semiconductor switching rather than mechanical contacts, it provides silent operation, rapid switching response and freedom from contact bounce. This makes it useful in automated systems requiring frequent switching, provided the electrical load and thermal conditions remain within the manufacturer's specifications.

Thermal Management and Safe Installation

Correct thermal management is essential when installing the Finder 77.F1.8.230.8650. Solid state relays dissipate heat during conduction, and the heat generated increases with load current. The relay's 80 A rating is therefore dependent on suitable heatsinking and the specified installation conditions.

The device can be mounted directly onto suitable control cabinet sheet metal or an appropriately rated heatsink. The required thermal arrangement depends on the load current, ambient temperature, enclosure ventilation and mounting conditions. The manufacturer's thermal derating information should be used when selecting the heatsink and determining the permissible continuous current.

For high-current installations, the thermal interface between the relay and its mounting surface is particularly important. Correct mounting pressure and suitable thermal interface materials should be used where specified by the manufacturer to ensure effective heat transfer.

Appropriate upstream short-circuit protection must also be provided. Solid state relays can be vulnerable to excessive fault currents, so protective device selection should account for the semiconductor's electrical characteristics and the prospective fault current of the installation.

As with other solid state relays, the Finder 77.F1.8.230.8650 may allow a small leakage current when the output is switched off. It does not provide mechanical contact separation and must not be used as the sole means of safety isolation. A suitable mechanical disconnecting device should be installed wherever safe isolation is required.

Typical Applications

• High-current single-phase AC load switching.
• Industrial electric heating element control.
• Industrial ovens and process heating systems.
• Temperature-controlled manufacturing equipment.
• Industrial drying and curing systems.
• Resistive heating load switching.
• Commercial and industrial lighting control within suitable ratings.
• Automated manufacturing and processing machinery.
• Industrial temperature control panels.
• Contactor and solenoid control where electrically compatible.
• Industrial process control and automation systems.
• Electrical control cabinets and panel-mounted switching equipment.
• OEM equipment requiring silent high-current AC switching.
• Frequent-duty AC switching applications within the relay's specified limits.