Circular connectors are essential components in modern industrial automation, robotics, transportation, and energy systems. To guarantee correct mating, prevent mismatching, and maintain secure connections in demanding environments, connector coding systems are used.
M12 connector types are especially important because they provide different keying options for power, data, and signal transmission. This ensures that only the right plug fits the right socket which is an important safeguard in applications where a wrong connection could lead to system downtime, data loss, or equipment damage. The connector coding chart helps engineers quickly identify the right coding for each application, ensuring safe and efficient connections.
This page explains why codings exist, what benefits they bring, and how binder supports customers with a broad portfolio of coded connectors.
Why Connector Coding Matters in Industrial Applications
In industrial environments, connectors are disconnected and reconnected daily for maintenance, upgrades, or repairs. Misconnections can be costly and dangerous. Coding solves this challenge by:
- Preventing mismating: Pin and socket layouts only allow one correct configuration.
- Increasing reliability: Guarantees proper alignment before locking.
- Saving time: Enables quick, error-free installation in the field.
- Enhancing safety: Prevents system failures, short circuits, or incorrect voltage application.
Coding plays a critical role across industries where signal, data, and power must be transmitted without error.
Signal & Data Transmission
- Avoids cross-connections between control signals, sensors, and communication lines.
- Supports fieldbus systems like PROFIBUS and PROFINET.
- Ensures reliable Ethernet connections, including M12 D coded and M12 X coded options for 100 Mbit and 10 Gbit Ethernet.
Connector Coding Overview – From M5 to M16
binder provides a comprehensive portfolio of circular connectors with precise coding options – from M5, M8, M12, M16, 7/8” up to larger formats. Each series is engineered to meet industry-specific requirements. The most extensive product offerings regarding coding options are found in our M8 and M12 connector types.
M12 Series – The High-Runner in Automation
The M12 connector has become the standard in many industries due to its versatility and robust coding options. binder offers:
For signal and data transmission
- M12 A coded– Sensors, DC power, CAN, DeviceNet
- M12 B coded– PROFIBUS DP
- M12 D coded– 100 Mbit Ethernet, PROFINET, EtherCAT
- M12 X coded– High-speed Ethernet up to 10 Gbit/s
For power supplies
- M12 S coded and M12 K coded– AC power up to 630V/16A (e.g., drives, inverters)
- M12 T coded and M12 L coded – DC power up to 63V/16A (e.g., motors, fieldbus components, LED lighting)
M12 Connector Coding Chart (A, B, D, X, S, K, L, T, US)
The M12 connector has become the standard in the automation sector due to its combination of versatility, durability, and robust coding options. Its compact size and wide range of M12 connector types allow it to handle both signal and power transmission, making it suitable for sensors, actuators, fieldbus systems, and Ethernet networks. With codings such as A, B, D, X, L, T, and K, the M12 ensures reliable connections, prevents mismating, and withstands harsh industrial environments, including dust, moisture, and vibration.
M12 A-coded
M12 A-coded
| Current | Voltage | Protection | Contacts | Typical Applications |
|---|---|---|---|---|
Current 1.5 - 8 A | Voltage 30 - 250 VAC | Protection IP67/IP68/IP69K | Contacts 3 - 12 | Typical Applications Power, Signal, CAN, DeviceNet |
M12 B-coded
M12 B-coded
| Current | Voltage | Protection | Contacts | Typical Applications |
|---|---|---|---|---|
Current 4 A | Voltage 60 - 250 VAC | Protection IP67/IP68 | Contacts 4 - 5 | Typical Applications PROFIBUS DP |
M12 D-coded
M12 D-coded
| Current | Voltage | Protection | Contacts | Typlical Applications |
|---|---|---|---|---|
Current 4 A | Voltage 250 VAC | Protection IP67 | Contacts 4 | Typlical Applications Ethernet, EtherCAT, PROFINET, Sercos |
M12 X-coded
M12 X-coded
| Current | Voltage | Protection | Contacts | Typical Applications |
|---|---|---|---|---|
Current 0.5 A | Voltage 50 VAC / 60 VCD | Protection IP67 | Contacts 8 | Typical Applications Ethernet, PROFINET |
M12 S-coded
M12 S-coded
| Current | Voltage | Protection | Contacts | Typical Applications |
|---|---|---|---|---|
Current 12 A | Voltage 630 VAC | Protection IP67 | Contacts 3 + PE | Typical Applications Power supply |
M12 T-coded
M12 T-coded
| Current | Voltage | Protection | Contacts | Typical Applications |
|---|---|---|---|---|
Current 12 A | Voltage 60 VDC | Protection IP67 | Contacts 4 | Typical Applications Power supply |
M12 K-coded
M12 K-coded
| Current | Voltage | Protection | Contacts | Typical Applications |
|---|---|---|---|---|
Current 12 A | Voltage 630 VAC | Protection IP67 | Contacts 4 + PE | Typical Applications Power supply |
M8 Series – The little brother of M12 connectors
The M8 connector is often called the “little brother” of the M12 because it offers a compact, versatile solution for tight spaces while still providing reliable performance. Its M8 connector coding options make it a great all-rounder for signal, data, and power transmission in industrial automation, robotics, and sensor applications. Despite its smaller size, it delivers robust connections with protection against dust and moisture, making it ideal where space is limited but reliability is essential.
M8 A-coded
M8 A-coded
| Current | Voltage | Protection | Contacts | Typical Applications |
|---|---|---|---|---|
Current 1.5 - 4 A | Voltage 30 - 60 VAC | Protection IP65/IP67/IP68/IP69K | Contacts 3 - 8 | Typical Applications Power, Signal, CAN, DeviceNet |
M8 B-coded
M8 B-coded
| Current | Voltage | Protection | Contacts | Typical Applications |
|---|---|---|---|---|
Current 3 A | Voltage 30 - 60 VAC | Protection IP67/IP68/IP69K | Contacts 5 | Typical Applications PROFIBUS DP |
Conclusion
Connector coding is a small detail with a big impact on system safety and performance. With binder’s broad range of circular connectors – especially the versatile M12 connector types like M12 A coded, M12 D coded, M12 X coded, M12 L coded, M12 B coded, M12 T coded, and M12 K coded – engineers and technicians can rely on precise, error-free, and future-proof connections.
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