Solid State Relay 40A- KRES40C -Kayama

Technical Description

The Kayama KRES40C Solid State Relay SSR is an electronic device designed to switch alternating-current (AC) loads using a direct-current (DC) control signal.

The model features a 3–32 VDC control input, 24–380 VAC load output and stated rated current of up to 40 A, allowing integration into electrically compatible control and automation systems.

By using semiconductor components in the power stage, the KRES40C performs switching without the conventional mechanical contacts found in electromechanical relays.

Technical Characteristics

• Brand: Kayama
• Model: KRES40C
• Type: Solid State Relay — SSR
• Control input: 3–32 VDC
• Control type: DC
• Output voltage range: 24–380 VAC
• Output type: AC
• Stated rated current: up to 40 A
• Internal optical isolation: stated
• LED indicator: stated
• Mounting: panel mounting
• Switching technology: solid state
• Purpose: electronic switching, control and automation

Operating Principle

The KRES40C uses semiconductor components to electronically establish or interrupt current conduction in the power circuit.

When a compatible signal is applied to the 3–32 VDC control input, the internal circuit activates the power stage and switches a compatible load connected to the 24–380 VAC output.

Because power switching does not rely on conventional mechanical contacts, the solid-state relay eliminates the mechanical wear associated with opening and closing such contacts.

3–32 VDC Control Input

The KRES40C control input is specified for 3 to 32 VDC signals.

This allows integration with different electronic control systems provided that both control voltage and available output current are electrically compatible.

A voltage within this range alone should not be considered proof of compatibility with every controller. The electrical interface must be evaluated before installation.

24–380 VAC Output

The power output is designed to switch AC loads from 24 to 380 VAC.

Therefore:

• 3–32 VDC: control circuit;
• 24–380 VAC: power circuit.

The DC control input does not mean the output is intended for switching DC loads.

40 A Rated Current

The model has a stated rated current of up to 40 A.

This rating should not be considered independently when determining the actual usable current for an installation.

Selection should consider:

• load type;
• operating current;
• starting or surge current;
• ambient temperature;
• ventilation;
• thermal dissipation;
• switching frequency;
• duty cycle;
• mounting method;
• project safety margin.

Thermal Behavior

Solid-state relays generate heat in the semiconductor power stage while conducting current.

Proper thermal design is therefore essential, particularly at higher operating currents.

Depending on actual operating conditions, installation on a properly sized heat sink may be required.

Heat dissipation should be sized according to actual load current, ambient temperature, ventilation, duty cycle and mounting conditions.

Optical Isolation

The KRES40C is stated to have internal optical isolation.

This feature provides functional separation between the electronic control circuit and power stage.

No specific isolation voltage should be stated without supporting technical documentation.

LED Indicator

A stated LED indicator assists in identifying the control circuit status.

The LED must not be used as the sole method of confirming that a circuit is de-energized or safe for servicing.

Load Characteristics

The behavior of an SSR depends on the characteristics of the connected load.

Resistive loads can behave differently from motors, transformers, solenoids, capacitive loads and electronic power supplies.

Loads with high starting or surge current require appropriate analysis, and the relay should not be selected solely from the load's normal operating current.

Electrical Protection

The KRES40C does not replace circuit breakers, fuses or other required electrical protection devices.

Protection must be selected according to the power supply, load and installation characteristics.

Control System Integration

The 3–32 VDC input allows the KRES40C to be considered for use with various electronic control systems.

Before connection, verify:

• controller output voltage;
• available control current;
• SSR input requirements;
• control logic;
• required isolation;
• characteristics of the controlled load.

An appropriate intermediate interface should be used when necessary.

Mounting

The KRES40C is designed for panel mounting.

Installation should provide suitable mechanical fastening, electrical connections, ventilation and thermal dissipation.

Installation and Safety

Installation should be performed by technically qualified personnel.

Before energizing, verify control voltage, load voltage, load current, load characteristics, electrical protection, thermal dissipation, connections and panel safety.

Disconnect and verify absence of voltage before installation or maintenance and allow the relay and heat sink to cool when applicable.

The KRES40C should not be used by itself as a functional safety device for machinery or processes.

Registration Information

• Brand: Kayama
• Model: KRES40C
• Rated current: 40 A
• Control input: 3–32 VDC
• Output: 24–380 VAC
• GTIN/EAN: 7900370024558

Kayama Quality

The KRES40C Solid State Relay is part of Kayama's range of components for electrical control and automation, providing electronic switching of AC loads through a DC control signal.