Finder 55.33.8.400.5000 – 55 Series Industrial relays

Why Choose the Finder 55.33.8.400.5000 Industrial Relay?

The Finder 55.33.8.400.5000 is a miniature industrial electromechanical relay from the Finder 55 Series, featuring three changeover contacts and a plug-in construction for use with compatible relay sockets. Designed for electrical control, automation and switching applications, the relay provides flexible switching through its 3 CO / 3PDT contact arrangement.

The part number identifies a 400 V AC nominal coil and the 5000 gold-plated contact configuration. Gold-plated contacts can offer advantages in applications involving low-level signals, while the relay's changeover contact arrangement supports multiple control and signalling functions.

The Finder 55.33 relay family is commonly used in industrial control panels, machinery and building automation systems. Its plug-in construction allows installation into compatible Finder 94 Series relay sockets, supporting convenient maintenance and replacement without directly soldering the relay into the control assembly.

Key Advantages

• Three changeover contacts provide flexible switching for multiple control circuits.
• 400 V AC nominal coil designation for specialised AC control applications.
• Gold-plated contact configuration for applications where contact surface characteristics are important.
• Plug-in relay construction enables convenient installation and replacement.
• Compatible with suitable Finder 94 Series sockets for control panel integration.
• Electromechanical switching provides physical contact separation between switched circuits.
• Compact miniature relay design helps conserve space in electrical assemblies.
• Three-pole switching arrangement supports industrial control and signalling functions.
• Monostable operation returns the contacts to their normal positions when the coil is de-energised.
• Finder 55 Series platform provides access to compatible sockets and accessories.

Key Features

• Finder 55 Series miniature general-purpose relay.
• 55.33 three-pole relay type.
• 400 V AC nominal coil designation.
• AC electromagnetic coil.
• Three changeover contacts (3 CO).
• Triple-pole double-throw (3PDT) contact arrangement.
• Gold-plated contact version.
• Plug-in mounting configuration.
• Compatible Finder 94 Series socket system.
• Monostable electromechanical operation.
• Separate normally open and normally closed switching paths for each pole.
• Suitable for industrial control and automation applications.

Technical verification note: The ratings identified above as 55.33 family values are general series specifications, not independently confirmed ratings for the exact 55.33.8.400.5000 variant. In particular, the 400 V AC coil option, its operating frequency and tolerance, and the permissible switching ratings of the gold-plated contacts should be confirmed against the manufacturer's variant-specific documentation before specification or installation.

Flexible Three-Pole Changeover Switching

The Finder 55.33.8.400.5000 uses a 3PDT contact arrangement, meaning it contains three separate changeover contact sets operated by a common electromagnetic coil. Each pole provides a common terminal, a normally closed terminal and a normally open terminal.

When the coil is energised at its specified operating voltage, the relay changes the position of all three contact sets. Removing the coil supply returns the relay to its normal state. This arrangement can be useful where a single control signal must operate multiple switching or signalling circuits.

The gold-plated contact configuration can be advantageous for low-level switching applications because gold surfaces resist oxidation. However, the minimum switching load, contact plating thickness and permissible current for this exact variant should be checked before use. High-current switching may affect the suitability of gold-plated contacts for subsequent low-level signal applications.

Plug-In Installation and Control Panel Maintenance

The Finder 55.33 relay design uses a plug-in mounting arrangement compatible with selected Finder 94 Series sockets. Depending on the selected socket, the assembly can be incorporated into DIN rail-mounted control panels or other suitable electrical installations.

Plug-in relay systems are particularly useful for maintenance because a relay can be replaced without removing the entire socket wiring assembly. Correct socket selection, electrical clearances, terminal ratings and coil supply compatibility remain essential, particularly for this high-voltage AC coil designation.

Typical Applications

• Industrial electrical control panels.
• Machinery control and automation equipment.
• Multi-circuit signalling and control systems.
• Industrial process control interfaces.
• Building automation equipment.
• Electrical interlocking and auxiliary control circuits.
• Alarm and status indication systems.
• OEM electrical control assemblies.
• Plug-in relay installations requiring three changeover contacts.
• Specialised AC control systems requiring a correctly verified high-voltage coil.