KSI240D25-L 25A 240VAC SSR 4-32VDC Zero Cross Relay with LED

The KSI240D25-L Solid State Relay (SSR) is a high-performance single-phase AC switching device designed for industrial automation, process control, and power management applications. With a robust 25A load rating and zero-cross switching technology, this relay delivers reliable, silent, and maintenance-free operation while minimizing electrical noise and reducing stress on connected equipment.

Featuring a wide 4-32VDC control input range, the KSI240D25-L can be directly interfaced with PLCs, microcontrollers, industrial controllers, sensors, and automation systems. Its low input current requirement of only 25mA maximum ensures efficient operation while maintaining excellent switching reliability.

The relay is capable of controlling AC loads from 48VAC to 280VAC, making it suitable for a broad range of industrial applications including heaters, lighting systems, motors, pumps, compressors, and other power control equipment. The integrated LED status indicator provides instant visual confirmation of relay activation, simplifying diagnostics and maintenance.

Built for demanding environments, the KSI240D25-L offers exceptional surge handling capability with a peak surge current of 400A (10ms) and an I t rating of 900A s. Combined with transient overvoltage protection up to 600V peak, these features help protect both the relay and connected loads from electrical disturbances.

The relay's zero-cross switching mode activates the load only when the AC waveform crosses zero voltage, significantly reducing electromagnetic interference (EMI), minimizing inrush current, and extending the service life of connected equipment. High dielectric isolation of at least 4000Vrms between input and output circuits ensures superior electrical safety and system protection.

For optimal thermal performance, the KSI240D25-L is compatible with KHS-1A, KHS-1B, and KHS-1C heatsinks, while the optional KPC-0A protective cover provides additional installation safety and protection.

Features

Single-phase AC output Solid State Relay

25A continuous load current capacity

Wide 4-32VDC control input range

Zero-cross switching technology

Built-in LED status indicator

Suitable for resistive, inductive, and capacitive loads

Silent operation with no moving parts

High surge current capability of 400A (10ms)

High dielectric isolation for improved safety

Low control current consumption

Maintenance-free operation

Compatible with KPC-0A protective cover

Compatible with KHS-1A, KHS-1B, and KHS-1C heatsinks

Specifications

Model: KSI240D25-L

Device Type: Solid State Relay (SSR)

Output Type: Single-Phase AC Output

Switching Mode: Zero Crossing

Status Indication: LED Indicator

Dimensions: 58.6 × 45.7 × 26.5mm

Control Voltage Range: 4-32VDC

Minimum Turn-On Voltage: 4VDC

Minimum Turn-Off Voltage: 1VDC

Maximum Input Current: 25mA

Load Voltage Range: 48-280VAC

Rated Load Current: 25A

Maximum Turn-On Time: AC Cycle + 1ms

Maximum Turn-Off Time: AC Cycle + 1ms

Maximum Surge Current (10ms): 400A

Maximum I t for Fusing (10ms): 900A s

Transient Overvoltage: 600V Peak

Dielectric Strength (Input/Output): 4000Vrms

Dielectric Strength (Output/Base): 2500Vrms

Suitable Cover: KPC-0A

Suitable Heatsinks: KHS-1A, KHS-1B, KHS-1C

Applications

Industrial automation systems

PLC-controlled equipment

Electric heating control

HVAC systems

Lighting control panels

Motor and pump switching

Packaging machinery

Process control systems

Temperature control equipment

General AC power switching applications

What's in the box
1 x KSI240D25-L 25A 240VAC SSR 4-32VDC Zero Cross Relay with LED