Omron MY4IN-CR 110/120VAC (S) Miniature Power Relay Guide

The Omron MY4IN-CR 110/120VAC (S) miniature power relay is a plug-in industrial relay designed for control systems using 110/120 VAC coil voltage. It is part of Omron’s MY relay series and is widely used in electrical panels, machine control circuits, auxiliary switching, and industrial automation applications.

This relay is designed with a 4PDT contact form, meaning it provides four independent changeover contacts in one compact device. A single coil command can switch four separate circuits at the same time. This makes it useful in applications where signal distribution, interlocking, indication, and auxiliary control must be handled from one control source.

Technical Overview

The MY4IN-CR 110/120VAC (S) version uses an AC coil and includes CR circuit surge absorption. In AC relay circuits, switching the coil can create electrical noise and transient voltage. The built-in CR suppression circuit helps reduce these effects and supports smoother relay operation in control panels.

The relay also includes LED indication, a mechanical indicator, a lockable test button, plug-in terminals, and a transparent case. These features support both installation and maintenance. The LED indicator helps technicians see when the coil is energized, while the mechanical indicator provides a physical confirmation of relay state.

Why CR Surge Absorption Matters

CR surge absorption is especially valuable in AC control circuits. It helps manage voltage transients and electrical noise that may occur during coil switching. This can improve compatibility with control devices, reduce nuisance behavior, and support cleaner operation in machine panels.

For maintenance teams, built-in suppression also reduces the need for external suppression components in many applications. This can simplify panel design and help keep wiring layouts more organized.

Typical Applications

The Omron MY4IN-CR 110/120VAC (S) miniature power relay is commonly used in automation cabinets, HVAC control panels, machine tools, process equipment, packaging machines, pump systems, and general industrial control circuits. Its 110/120 VAC coil rating makes it suitable for control systems where this voltage level is already available.

In practical use, one contact may be used for a control signal, another for an indicator lamp, another for feedback, and another for auxiliary logic. This flexibility makes the relay useful when several actions must occur from a single control event.

Installation and Service Value

The plug-in design helps reduce maintenance time. When used with a compatible socket, the relay can be removed and replaced without rewiring the connected circuits. This is especially useful in production environments where downtime must be controlled.

The lockable test button can support controlled testing during commissioning and troubleshooting. The transparent case allows visual inspection of the internal relay mechanism, helping technicians understand the relay status quickly.

For more technical product browsing, visit Omron relay information.

Frequently Asked Questions

What is the Omron MY4IN-CR 110/120VAC (S) miniature power relay used for?

It is used for switching multiple control circuits in systems that operate with a 110/120 VAC relay coil supply.

What does CR mean in this relay model?

CR refers to a built-in resistor-capacitor surge absorption circuit. It helps reduce coil switching noise and transient voltage in AC control circuits.

What does 4PDT mean?

4PDT means four pole double throw. The relay has four independent changeover contacts that switch together when the coil is energized.

Does this relay have an LED indicator?

Yes. The LED indicator provides a visual signal when the relay coil is energized, helping with inspection and troubleshooting.

Can this relay be used in DC circuits?

This specific model is intended for 110/120 VAC coil operation. DC coil applications require a DC-rated relay model.

Omron MY4IN-CR 110/120VAC (S) Why is the test button useful?

The test button allows controlled relay actuation during testing, commissioning, or maintenance, provided all safety procedures are followed.

Is this relay suitable for industrial panels?

Yes. It is designed for general-purpose industrial control use and is commonly installed in control cabinets and automation systems.