The M12 A-code is a prevalent circular connector coding system in industrial automation, designed to differentiate M12 connectors by their intended applications. Typically employed for transmitting signals and DC power, the specific functions and typical applications of A-code connectors vary according to their pin count (number of contacts).
M12 A-code Connector Pin Count Comparison
| Pin Count | Signal Type | Power Rating | Typical Applications |
|---|---|---|---|
| 3-pin | Sensor signals | 24V DC/2A | Proximity sensors, IO-Link devices |
| 4-pin | Mixed signals + power | 24V DC/4A | PLC I/O modules, small actuators |
| 5-pin | Fieldbus protocols | 24V DC/8A (shielded) | PROFINET, EtherNet/IP, CANopen networks |
| 8-pin | High-speed data | 60V DC/12A (IP67) | Industrial Ethernet, vision systems |
How to choose the right number of pins?
The number of pins for M12 A-code needs to be determined based on the device interface requirements, signal type and quantity, and power supply requirements:
- Power supply only/basic switch sensor → select 3-pin or 4-pin
- Dual signal output or shield required → select 5-pin
- Compound signal, multi-function sensor → select 8-pin or 12-pin
