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RUGGED COMPUTING · CONNECTORS

Which M12 Codings Are Used for Power?

M12 power connectors use dedicated codings. L and T coding carry DC power, up to 16 A and 12 A at 63 V; S and K coding carry AC power up to 630 V. The older C coding was used for AC sensors and power. Low-current DC supplies, such as a computer's power input, often use A coding.

01

The Short Answer

Power codings were added to the IEC 61076-2-111 standard so that M12 could replace larger power connectors on machines. Each has its own key, so a power cable cannot be connected to a signal or Ethernet socket.

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    L-coded DC power up to 16 A at 63 V, typically for PROFINET devices.
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    T-coded DC power up to 12 A at 63 V, 4 contacts.
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    S-coded AC power up to 630 V, with a protective earth.
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    K-coded AC power up to 630 V with 4 contacts and earth, including three-phase.
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    C-coded Older AC coding for sensors and power, being replaced by S and K.
02

Power on Industrial Computers

Most industrial computers take a low-voltage DC supply through an A-coded M12 connector, from 9 V up to 110 V on railway models, because the current is modest. Higher-current field power uses L-coded M12. Our guide to M12 connectors compares every coding, and the M12 coding FAQ explains how coding works.