RS1A40A4-25 - SSR ZS 400V 25A 400VAC LED

RS1A40A4-25 – SSR ZS 400V 25A 400VAC LED

Carlo Gavazzi RS1A40A4-25 solid state relay, a 25 A single-phase zero-cross switching relay with 360–440 V AC control input designed for industrial AC load control applications.

SKU: RS1A40A4-25Alt SKU: RS1A40A425MPN: RS1A40A4-25
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Why Choose the Carlo Gavazzi RS1A40A4-25 Solid State Relay?

The Carlo Gavazzi RS1A40A4-25 is a robust single-phase solid state relay (SSR) designed for reliable switching of AC loads in industrial automation, heating control and electrical power applications. As part of the proven Carlo Gavazzi RS1A solid state relay series, it combines zero-cross switching technology with a compact panel-mount design to provide dependable, silent and long-life electronic switching performance.

This industrial solid state relay uses semiconductor switching technology to eliminate mechanical contact wear while providing fast and reliable control of AC loads. Its screw terminal connections, LED status indication and compact enclosure make it suitable for integration into electrical control panels, machinery and automation systems.

With a rated load current of 25 A AC, an operating voltage range of 42–440 V AC and a 360–440 V AC control input, the RS1A40A4-25 is designed for dependable single-phase AC switching in demanding industrial environments.

Key Advantages

  • Reliable solid state relay designed for industrial switching applications.
  • 25 A AC load current rating suitable for industrial power control.
  • Zero-cross switching technology reduces electrical noise and switching stress.
  • 360–440 V AC control input for high-voltage control applications.
  • Compact panel mount design for industrial control cabinets.
  • Silent semiconductor switching with no mechanical contact degradation.

Key Features

  • Carlo Gavazzi RS1A solid state relay series.
  • 25 A rated AC load current.
  • 42–440 V AC operating voltage range.
  • 360–440 V AC control voltage range.
  • Zero-cross output switching for AC loads.
  • Single-phase switching configuration.
  • Integrated LED status indication.
  • Panel mounting format with screw terminals.

Reliable Solid State Switching for Industrial Automation

Solid state relays such as the Carlo Gavazzi RS1A40A4-25 provide dependable electronic switching for industrial loads by using semiconductor technology instead of mechanical contacts. This enables silent operation, fast response and improved reliability in automated systems.

The RS1A series is designed for industrial control applications where consistent AC load switching is required. Its zero-cross switching capability helps minimise electrical interference and supports reliable operation in machinery, process control and automation installations.

Typical Applications

  • Industrial heating and temperature control systems.
  • Automation control panels.
  • Machine building and OEM equipment.
  • Process control systems.
  • Electrical load switching applications.
  • Industrial equipment requiring reliable AC switching.

Technical Specifications

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Device Type Solid State Relay
Terminal Type Screw
Mounting Type Panel
Switching Current (A) 25 A
Coil / Supply Voltage 380 V AC, 400 V AC, 415 V AC, 440 V AC
Contacts 1NO
IP Rating IP20
Manufacturer Carlo Gavazzi
Series RS1A
Model RS1A40A4-25
Product type Solid state relay
Switching mode Zero cross
Number of poles 1
Number of phases 1-phase
Rated current AC-51 25 A
Operating voltage 42–440 V AC
Control voltage 360–440 V AC
Control frequency 50 / 60 Hz
Output type Thyristor
Contact configuration SPST
Protection rating IP20
Mounting type Panel mounting
Terminal type Screw connection with captive clamp
Dimensions approx. 44.8 × 58.2 × 28.8 mm
Weight approx. 60 g
Operating temperature -20 to +70 °C

Frequently Asked Questions

What is the Carlo Gavazzi RS1A40A4-25 used for?

The RS1A40A4-25 is a solid state relay used for switching single-phase AC loads in industrial automation and control applications.

What load current can the RS1A40A4-25 switch?

The relay is rated for a maximum operating current of 25 A AC for suitable AC-51 applications.

What control voltage does this solid state relay require?

The RS1A40A4-25 operates with a 360–440 V AC control input.

What type of switching does the RS1A40A4-25 provide?

The relay uses zero-cross switching to reduce electrical noise and switching stress when controlling AC loads.

How is the RS1A40A4-25 installed?

The RS1A40A4-25 is designed for panel mounting inside industrial control cabinets and electrical enclosures.

Trusted by Industrial Automation Engineers

Carlo Gavazzi solid state relays are widely used in industrial automation systems to provide reliable, long-life electronic switching for demanding control applications.

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