Finder 77.H1.8.230.8250 – 77 Series Modular solid state relays

Why Choose the Finder 77.H1.8.230.8250 Solid State Relay?

The Finder 77.H1.8.230.8250 is a high-capacity 125 A single-phase solid state relay (SSR) designed for dependable, silent and contactless switching of AC electrical loads. Part of the Finder Series 77 industrial solid state relay range, this semiconductor switching device is engineered for demanding industrial heating, automation, process control and electrical machinery applications requiring high switching endurance.

Unlike conventional electromechanical relays, the Finder 77.H1.8.230.8250 uses semiconductor technology to switch electrical loads without moving contacts. Its zero-crossing switching function activates the output near the zero-voltage point of the AC waveform, helping reduce switching interference and electrical stress in suitable applications. Contactless operation eliminates mechanical contact bounce and provides quiet switching for equipment requiring frequent or repetitive operation.

Featuring a 125 A rated output current, a 24–280 V AC switched load voltage range and a 90–280 V AC control input, the Finder 77.H1.8.230.8250 provides high-current AC load control from compatible industrial AC control circuits. Its compact hockey-puck housing, relay-style terminal arrangement and panel or heatsink mounting construction make it suitable for integration into industrial electrical control cabinets and power switching assemblies.

Key Advantages

• High-capacity 125 A single-phase solid state relay for demanding industrial AC switching applications.
• 24–280 V AC switched load voltage range supports a broad range of industrial electrical equipment.
• 90–280 V AC control input allows operation from compatible AC control circuits.
• Zero-crossing switching technology helps minimise electrical interference when controlling suitable AC loads.
• Contactless semiconductor operation provides silent, spark-free and bounce-free switching.
• High switching endurance without mechanical contact wear.
• 2,250 A maximum peak current for 10 ms provides a defined short-duration surge capability.
• Compact hockey-puck housing with a protective folding screw cover.
• Relay-style terminal arrangement separates control and load connections for convenient wiring.
• Flexible panel or heatsink mounting supports industrial power control assemblies.
• IP20 protection rating for installation inside suitable electrical enclosures.

Key Features

• Finder Series 77 industrial solid state relay.
• Type 77.H1 high-current single-phase configuration.
• 125 A rated output current with appropriate heatsink selection and thermal management.
• 24–280 V AC switched load voltage.
• 90–280 V AC control voltage range.
• 230 V AC nominal control voltage.
• Single-phase, 1 normally open (SPST-NO equivalent) output.
• Zero-crossing switch-on technology for suitable AC loads.
• Contactless semiconductor switching for high operational endurance.
• Silent operation without mechanical contact bounce.
• 2,250 A maximum peak current for 10 ms.
• 47–400 Hz output operating frequency range.
• Low control power compared with many mechanical switching arrangements.
• Relay-style input and output terminals positioned on opposite sides of the housing.
• Hockey-puck construction with folding screw terminal cover.
• Screw terminal connections for secure electrical wiring.
• Panel or heatsink mounting for industrial control assemblies.
• −30 to +80 °C ambient operating temperature range, subject to thermal derating.
• Suitable for industrial heater control, compatible lighting circuits, solenoids and contactor driver applications.

Reliable High-Current Solid State Switching for Industrial Automation

Solid state relays such as the Finder 77.H1.8.230.8250 use electronic semiconductor components rather than moving mechanical contacts to control electrical loads. When a compatible 90–280 V AC control signal is applied, the relay activates its AC output switching circuit. Its zero-crossing switching technology delays turn-on until the AC waveform approaches zero voltage, helping reduce switching disturbances when controlling suitable resistive loads. This operating principle makes the relay particularly useful for repetitive switching of electric heating elements and other compatible industrial equipment.

The Finder Series 77 is designed for applications requiring quiet operation, high switching endurance and dependable repetitive control. The 77.H1.8.230.8250 combines a substantial 125 A output rating with an AC switching voltage range suited to common industrial supplies, making it suitable for high-current heating, automated manufacturing and process control applications. Because semiconductor switching generates heat during operation, an appropriately sized heatsink and correct thermal derating are essential. Solid state relays also exhibit off-state leakage current and do not provide mechanical isolation, so correctly rated protective and isolation devices must be installed separately.

Typical Applications

• Industrial electric heating and temperature control systems.
• High-current resistive heater banks and heating element switching.
• Industrial ovens, furnaces and process heating equipment.
• Packaging and automated manufacturing machinery.
• Industrial lighting and compatible lamp switching circuits.
• Solenoid and contactor driver applications.
• PLC-controlled industrial switching and automation systems.
• Electrical control cabinets and industrial power switching assemblies.
• OEM machinery requiring silent, repetitive AC load switching.
• Industrial process control and automated electrical installations.