Omron MY3 220/240VAC General Purpose Relay Technical Guide

The Omron MY3 220/240VAC general purpose relay is a plug-in miniature power relay designed for control panels, automation cabinets, machine interfaces, and switching circuits that require dependable multi-pole isolation. This model belongs to Omron’s MY series, a widely used relay family for industrial control applications. The MY3 220/240VAC version is specified with a 220/240 VAC coil, plug-in terminals, 11-pin socket compatibility, a 3PDT contact arrangement, and a 5 A rated carry current. Omron lists the device with a transparent case, mechanical indicator, and label facility, making it practical for panel maintenance and circuit identification. :contentReference[oaicite:0]{index=0}

Key Technical Characteristics

This relay uses a 3PDT contact configuration, also known as three changeover contacts. That means one coil action can switch three independent circuits at the same time. In control cabinet design, this is useful when one signal must control several logic paths, auxiliary contacts, alarm circuits, or interlock functions. The 5 A rating makes it suitable for many control loads, while the plug-in format allows replacement without rewiring the relay body.

The 220/240 VAC coil version is typically selected where the control circuit uses mains-level AC voltage. Omron’s MY series coil data shows that 220/240 VAC coils have rated current values of approximately 4.8 mA at 50 Hz and 5.3 mA at 60 Hz, with a coil resistance reference value of 18,790 ohms. The must-operate voltage is listed as 80% maximum of rated voltage, while the must-release voltage is listed as 30% minimum for AC coils. :contentReference[oaicite:1]{index=1}

Where This Relay Fits Best

The Omron MY3 220/240VAC relay is often appropriate in electrical panels where the control voltage is already 230 VAC or similar. Typical uses include auxiliary switching, control relay logic, equipment status circuits, fan and pump control interfaces, alarm annunciation, and machine safety-adjacent signaling where a general purpose relay is acceptable. It is not a programmable device; instead, it provides a predictable electromechanical switching action that can be visually confirmed through its mechanical indicator.

Because it is socket mounted, technicians can service the relay faster than a soldered or fixed-terminal component. The 11-pin format also supports orderly panel layouts when used with the correct compatible socket. For more Omron relay information, visit Omron industrial automation components.

Design and Installation Notes

When selecting this relay, engineers should confirm coil voltage, contact load, load type, socket compatibility, ambient temperature, and switching frequency. Resistive loads are easier to switch than inductive loads, so motors, solenoids, and contactor coils may require additional suppression depending on the circuit. The MY series is specified for a broad operating temperature range, and Omron lists general MY relay ambient operating temperature values down to -55°C, with the upper range depending on model and conditions. :contentReference[oaicite:2]{index=2}

FAQ

What is the Omron MY3 220/240VAC relay used for?

It is used for general purpose switching in control panels, industrial automation systems, machine circuits, auxiliary signaling, and multi-circuit control applications where a 220/240 VAC coil is required.

What does 3PDT mean on this relay?

3PDT means three-pole double-throw. The relay can switch three separate circuits, and each circuit has a changeover contact with normally open and normally closed paths.

Is the Omron MY3 220/240VAC relay socket mounted?

Yes. It is a plug-in relay designed for use with a compatible 11-pin socket, which helps reduce maintenance time and simplifies panel replacement work.

Can this relay switch DC loads?

The contacts may be rated for certain DC loads, but the coil of this specific version is 220/240 VAC. The load rating must always be checked against the application current, voltage, and load type.

Why choose a 220/240 VAC coil relay?

This coil voltage is useful when the available control supply is mains-level AC. It avoids the need for a separate 24 VDC or 24 VAC control supply in suitable circuits.

Does this relay include a mechanical indicator?

Yes. Omron lists this model with a mechanical indicator, allowing easier visual confirmation of relay operation during inspection or troubleshooting.