Omron MY4 48/50VAC (S) General Purpose Relay for AC Control Applications
The Omron MY4 48/50VAC (S) general purpose relay is a plug-in electromechanical relay used in industrial control panels, auxiliary switching circuits, automation systems, and machine control applications. It belongs to the Omron MY miniature power relay series, a long-established relay family known for practical socket mounting, compact design, and dependable multi-contact switching.
This model is designed for 48/50 VAC coil operation. It is often used in control circuits where an intermediate AC control voltage is preferred. With a 4PDT contact arrangement, the relay gives engineers four changeover contacts in one device, allowing one coil signal to control several independent circuit paths.
Technical Overview
The Omron MY4 48/50VAC (S) relay is commonly specified as a plug-in relay with 4PDT contacts and a 48/50 VAC coil. It is part of the MY series for general-purpose industrial relay applications. The relay format supports socket installation, making it suitable for control cabinets where easy replacement and organized wiring are important.
The 4PDT structure means that the relay includes four separate changeover contacts. When the coil is energized, all four contacts change state together. This makes the relay useful for applications where one command must trigger multiple control functions, such as signaling, interlocking, status feedback, and auxiliary circuit switching.
Typical Applications
The Omron MY4 48/50VAC (S) general purpose relay can be used in automation panels, packaging machines, conveyor systems, pump controls, control transformers, alarm circuits, and older industrial machines that use 48 VAC control architecture. It may also appear in retrofit or maintenance projects where the existing panel design is based on 48/50 VAC relay coils.
Because it is socket-mounted, this relay supports faster service operations. A technician can remove the relay from its socket and install a replacement without disturbing the full wiring layout. This is particularly valuable in production environments where downtime must be minimized.
Key Features
- Brand and model: Omron MY4 48/50VAC (S)
- Product type: General purpose electromechanical relay
- Coil voltage: 48/50 VAC
- Contact form: 4PDT
- Mounting style: Plug-in socket relay
- Application area: Industrial control and auxiliary switching
- Relay series: Omron MY miniature power relay series
Important Design Considerations
When specifying the Omron MY4 48/50VAC (S), the first point to verify is the coil supply. A 48/50 VAC relay must be energized with the correct AC control voltage. It should not be replaced with a 48 VDC relay unless the panel design and supply are changed accordingly. AC and DC relay coils behave differently, even when the voltage number looks similar.
The second point is contact loading. Relays may have different ratings for resistive and inductive loads. Resistive loads, such as heating elements or simple indicator circuits, are typically less demanding. Inductive loads, such as coils, solenoids, and contactors, can create arcing and electrical stress at the contacts. Correct suppression and derating help protect the relay and improve reliability.
For additional Omron relay options and compatible automation parts, visit Omron industrial relay products.
FAQ
What is the Omron MY4 48/50VAC (S) used for?
It is used for switching multiple circuits in industrial control systems that use a 48/50 VAC relay coil supply. Typical applications include control panels, machinery, auxiliary logic, alarms, and interlock circuits.
Is Omron MY4 48/50VAC (S) a plug-in relay?
Yes. It is designed for plug-in socket installation, which makes wiring cleaner and replacement easier during maintenance.
What does 4PDT mean on this relay?
4PDT means four-pole double-throw. The relay has four independent changeover contacts operated by one coil.
Can this relay replace a 48VDC relay?
No. A 48/50 VAC relay and a 48 VDC relay are not direct substitutes. The coil type must match the control voltage and current type used in the circuit.
Why would a system use 48/50 VAC?
Some industrial control systems use intermediate AC control voltages for safety, compatibility, transformer-based control circuits, or legacy panel design. The relay should match the existing electrical architecture.
Is it suitable for inductive loads?
It can switch inductive loads within the correct rating, but inductive loads require care. Surge suppression and correct load matching help reduce contact wear and prevent premature failure.
What should be checked before ordering?
Check the exact coil voltage, relay type, contact form, socket compatibility, contact rating, load type, panel wiring diagram, and any required approvals. These details help avoid incorrect replacement.
Why is Omron MY4 48/50VAC (S) popular in maintenance work?
It is compact, socket-mounted, and part of a well-known relay family. These qualities make it practical for replacement, troubleshooting, and standardized control panel designs.