Finder 22.21.8.120.4000 – 22 Series Modular monostable relays

Why Choose the Finder 22.21.8.120.4000 Modular Installation Relay?

The Finder 22.21.8.120.4000 is a compact 20 A modular installation relay designed for reliable electrical load switching in lighting, building services and automation installations. Part of the Finder 22 Series, this monostable relay combines a 120 V AC operating coil with a single normally open contact, providing straightforward remote switching from a suitable control circuit.

Featuring a 1 NO (SPST-NO) contact configuration, the Finder 22.21.8.120.4000 is designed to switch compatible electrical loads with a rated contact current of 20 A. Its silver tin oxide (AgSnO2) contact material makes it suitable for appropriately rated applications involving lighting and electrical loads with switching demands.

With a slim 17.4 mm modular width and direct mounting onto a 35 mm DIN rail, this installation relay provides a space-efficient solution for electrical distribution boards and control panels. Its monostable operation ensures that the normally open contact returns to its unenergised position when the coil supply is removed.

Key Advantages

• 20 A rated switching current for compatible electrical loads.
• 120 V AC operating coil for suitable control circuits.
• Single normally open contact for straightforward electrical switching.
• Monostable operation automatically returns the contact to its normal state when de-energised.
• AgSnO2 contact material for dependable electrical switching performance.
• 17.4 mm slimline construction helps conserve DIN rail space.
• Direct mounting onto standard 35 mm DIN rail.
• IP20 protection rating for installation inside suitable electrical enclosures.
• Suitable for electrical distribution, lighting control and building automation applications.
• Part of Finder's established 22 Series modular relay range.

Key Features

• Finder 22 Series modular monostable installation relay.
• Type 22.21 single-pole switching arrangement.
• 1 NO (SPST-NO) contact configuration.
• 20 A rated contact current.
• 120 V AC rated coil voltage.
• 250 V AC rated contact voltage.
• 400 V AC maximum switching voltage.
• 30 A maximum peak contact current.
• Silver tin oxide (AgSnO2) contact material.
• Monostable electromagnetic relay operation.
• Compact 17.4 mm modular housing.
• Direct 35 mm DIN rail mounting to EN 60715.
• IP20 enclosure protection rating.
• Suitable for continuous-duty control applications within the specified ratings.
• Designed for integration into electrical distribution and automation panels.

Reliable Modular Switching for Electrical Control and Automation

Modular installation relays provide an effective method of controlling electrical loads from a separate control circuit. The Finder 22.21.8.120.4000 uses an electromagnetic coil to operate a normally open contact, allowing suitable lighting or building services equipment to be switched remotely.

When the 120 V AC coil is energised, the relay closes its normally open contact and completes the connected load circuit. When the coil is de-energised, the contact returns to its open position. This monostable switching arrangement is particularly useful where electrical equipment must operate only while a control signal is present.

The 20 A rated contact and AgSnO2 contact material support dependable switching of compatible electrical loads. Its compact modular construction makes it suitable for distribution boards, electrical control cabinets and building automation panels where installation space is limited.

For reliable operation, the connected equipment must remain within the relay's specified electrical ratings. Loads with significant starting currents, including motors and certain LED drivers, should be assessed against the appropriate utilisation category and inrush-current limits rather than the nominal 20 A rating alone.

Typical Applications

• Electrical distribution board switching.
• Commercial and industrial lighting control.
• Building automation and electrical control systems.
• Remote switching of compatible lighting circuits.
• Electrical installation control panels.
• Office and commercial building services.
• Automatic lighting control installations.
• Control of appropriately rated electrical equipment.
• Electrical refurbishment and panel upgrades.
• DIN rail-mounted relay replacement applications.