27.21.8.230.4000 Finder Step relay Clamp terminal

27.21.8.230.4000 Finder Step relay Clamp terminal

Finder 26.03.8.230.4000 is a Series 26 electromechanical impulse step relay featuring a 230 V AC coil, one normally open and one normally closed 10 A contact, and mechanically maintained switching for lighting and electrical control applications.

SKU: 27.21.8.230.4000Alt SKU: 272182304000MPN: 27.21.8.230.4000
Price
List Price £10.54 ex VAT
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Why Choose the Finder 27.21.8.230.4000 Impulse Step Relay?

The Finder 27.21.8.230.4000 is a compact 10 A electromechanical impulse step relay designed for lighting control and fixed electrical installations. Part of the Finder Series 27 range, it provides convenient switching through momentary push-button operation.

Featuring a 230 V AC operating coil and one normally open (1 NO) contact, this relay allows a lighting circuit to be switched using successive control impulses. Its mechanically maintained operating principle means the selected contact position is retained after the control impulse ends.

The Finder 27.21.8.230.4000 combines a 10 A contact rating with a compact installation format suitable for recessed electrical mounting boxes and appropriate panel installations. It is a practical solution for residential and commercial lighting systems requiring control from multiple push-button locations.

Key Advantages

  • 10 A impulse step relay for lighting and electrical switching.
  • 230 V AC coil for compatible mains-voltage control circuits.
  • One normally open contact for single-circuit switching.
  • Mechanically maintained switching without continuous coil energisation.
  • Supports lighting control from multiple momentary push-buttons.
  • Compact design suitable for recessed electrical installations.
  • Electromechanical operation provides straightforward switching control.
  • Suitable for residential, commercial and building services applications.

Key Features

  • Finder Series 27 electromechanical impulse relay.
  • Type 27.21 single-contact switching arrangement.
  • 230 V AC nominal coil voltage.
  • 50/60 Hz AC control supply.
  • 1 NO (SPST-NO) contact configuration.
  • 10 A rated switching current.
  • 250 V AC rated contact voltage.
  • Two-position impulse switching operation.
  • Mechanically maintained contact position.
  • Silver tin oxide (AgSnO2) contact material.
  • Compact mounting-box installation format.
  • Suitable for momentary push-button control.

Efficient Single-Circuit Lighting Control with Impulse Switching

The Finder 27.21.8.230.4000 uses an electromechanical impulse mechanism that changes its normally open contact between the open and closed positions when a suitable control pulse is applied. After the impulse ends, the mechanical mechanism maintains the selected position without continuous coil power.

This arrangement makes the relay particularly useful for lighting circuits operated from several locations. Momentary push-buttons can provide control impulses to the relay, allowing convenient switching in corridors, staircases, shared spaces and other fixed electrical installations. The connected load must remain within the manufacturer's applicable switching ratings.

Typical Applications

  • Residential lighting control.
  • Staircase and corridor lighting systems.
  • Commercial building lighting installations.
  • Multi-location lighting control using momentary push-buttons.
  • Office and shared-area lighting.
  • Building automation switching circuits.
  • Recessed electrical installation boxes.
  • Single-circuit impulse-controlled electrical switching.

Technical Specifications

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Timing Function Pulse
Mounting Type Panel
Device Type Single-function timer
Switching Current (A) 10 A
Manufacturer Finder
Series Series 27
Model 27.21.8.230.4000
Product type Electromechanical impulse step relay
Nominal coil voltage 230 V AC
Coil frequency 50/60 Hz
Control voltage range 184–253 V AC
Number of contacts 1
Contact configuration 1 NO (SPST-NO)
Rated contact current 10 A
Rated contact voltage 250 V AC
Switching sequence Two-position impulse switching
Relay operation Mechanically maintained
Contact material Silver tin oxide (AgSnO2)
Maximum incandescent lamp load 2000 W
Maximum fluorescent lamp load 500 VA for the specified lamp arrangement
Installation depth 21.5 mm
Mounting Suitable recessed electrical mounting box or panel installation
Manual operating control No

Frequently Asked Questions

What is the Finder 27.21.8.230.4000 used for?

It is a 10 A impulse step relay used for lighting and electrical switching, particularly where a circuit needs to be controlled from multiple momentary push-buttons.

What coil voltage does this relay require?

The Finder 27.21.8.230.4000 uses a 230 V AC nominal coil operating at 50/60 Hz.

How many contacts does the Finder 27.21.8.230.4000 have?

It has one normally open (1 NO) contact for switching a single electrical circuit.

What is the rated contact current?

The relay has a 10 A rated contact current and a rated contact voltage of 250 V AC. Load-specific switching limits must also be observed.

Does the relay need continuous coil power to stay switched on?

No. Its mechanically maintained impulse mechanism retains the selected contact position after the control impulse ends.

Can the Finder 27.21.8.230.4000 control lighting from several locations?

Yes. A suitable control circuit can use multiple momentary push-buttons to operate the relay from different locations.

Where is this relay typically installed?

It is suitable for installation in an appropriate recessed electrical mounting box or compatible panel arrangement, with access and wiring provisions appropriate to the installation.

Trusted by Electrical Contractors and Lighting Control Professionals

Finder Series 27 impulse relays offer practical switching solutions for electricians, lighting installers and building services engineers. The Finder 27.21.8.230.4000 combines 230 V AC impulse control, a 10 A normally open contact and compact installation for dependable multi-location lighting operation.

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