Omron MY4IN1-D2 48VDC (S) Miniature Power Relay Guide
The Omron MY4IN1-D2 48VDC (S) miniature power relay is a plug-in industrial relay designed for control circuits that operate with a 48 VDC coil supply. It belongs to Omron’s MY series, a well-known relay family used in automation panels, machine control systems, signal switching circuits, and industrial electrical cabinets.
This model is commonly specified as a 4PDT relay, also described as a four-pole changeover relay. That means one energized coil can operate four independent changeover contacts at the same time. This structure is useful when one control signal must switch several isolated circuits, such as status indication, auxiliary control, alarm routing, PLC feedback, and interlock logic.
Technical Characteristics
The MY4IN1-D2 48VDC (S) version is designed for DC coil operation and includes a built-in diode for coil surge absorption. When a DC relay coil is switched off, stored magnetic energy can create reverse voltage. The integrated diode helps limit that voltage and supports more stable operation when the relay is driven by PLC outputs, transistor outputs, or electronic control modules.
The relay includes a mechanical indicator, LED operation indicator, lockable test button, plug-in terminals, and transparent case design. These features are practical in real maintenance environments. The LED gives a clear visual signal when the coil is energized, while the mechanical indicator supports quick inspection even when panel lighting is limited.
Why 48 VDC Is Used
48 VDC control voltage is often found in industrial systems where a higher DC control level is preferred over 24 VDC. It may be used in larger machines, transportation-related systems, process control panels, energy systems, battery-backed control cabinets, and distributed automation equipment.
The Omron MY4IN1-D2 48VDC (S) miniature power relay is useful in these environments because it combines compact relay construction with multi-contact switching. Its 4PDT configuration allows engineers to reduce component count when multiple switching paths are required from one command signal.
Common Applications
This relay may be used for control signal multiplication, interface switching, alarm logic, status output circuits, machine sequencing, auxiliary control, and electrically isolated switching between control devices. In a control cabinet, one relay can manage several low-power circuits while maintaining separation between each contact set.
For example, one contact may provide a signal to a PLC input, another may operate an indicator lamp, another may trigger an auxiliary relay, and another may be used in a permissive or interlock circuit. This makes the relay valuable where clean, organized control logic is required.
Maintenance Benefits
The plug-in design improves serviceability. When installed with a compatible socket, the relay can be replaced without disturbing the field wiring. This reduces downtime and supports structured maintenance procedures. The test button can also help technicians verify circuit behavior when used under safe and approved conditions.
Omron MY4IN1-D2 48VDC (S) For more technical product browsing, visit Omron relay information.
Frequently Asked Questions
What is the Omron MY4IN1-D2 48VDC (S) miniature power relay?
It is a plug-in electromechanical relay with a 48 VDC coil, 4PDT contact arrangement, LED indication, mechanical indication, test button, and built-in diode surge absorption.
What does 4PDT mean in this relay?
4PDT means four pole double throw. The relay has four independent changeover contacts that operate together when the coil is energized.
Why does this model include a diode?
The diode helps suppress reverse voltage generated by the DC coil when power is removed. This is especially useful when the relay is controlled by electronic outputs.
Omron MY4IN1-D2 48VDC (S) Can this relay be used in 24 VDC circuits?
No. This specific model is designed for 48 VDC coil voltage. A 24 VDC circuit should use the correct 24 VDC relay model.
Is the LED indicator useful during troubleshooting?
Yes. The LED helps confirm whether the coil is receiving power, making fault diagnosis faster in control panels and automation systems.
Is this relay suitable for socket mounting?
Yes. It is a plug-in relay intended for use with compatible relay sockets, allowing easier replacement and cleaner panel wiring.
Where is this relay commonly installed?
It is commonly installed in automation cabinets, machine panels, process control systems, signal interface circuits, and industrial switching applications.