M12 Connector Specifications: Current, Voltage, Temperature & IP

On this page

• Quick Answer
• M12 Specifications by Coding
• Rated Current
• Rated Voltage
• Operating Temperature Range
• Ingress Protection (IP Rating)
• Mating Cycles, Contact and Insulation Resistance
• Connector Rating vs Cable Rating
• How to Read M12 Specifications for Selection
• Key Takeaways
• FAQ

Quick Answer

M12 connector specifications are not a single set of numbers — they follow the coding's electrical role. Signal and Ethernet codings carry low current and voltage (Ethernet codings as low as ~0.5 A at ~50 V), while power codings carry much more (T-coded DC up to ~12 A at ~63 V; K-coded AC up to ~16 A at ~630 V). Across the range, M12 connectors are commonly sealed to IP67 (with IP68/IP69K options), rated for −40 to +85 °C, and good for at least 100 mating cycles. This guide breaks the key specifications down by coding and explains how to read each one when selecting a connector.

M12 Specifications by Coding

The single most important fact about M12 specifications is that the electrical rating tracks the coding, because each coding was designed for a particular job. The table below compares the rated current and voltage across the codings — notice how the figures rise sharply from signal and Ethernet codings to the power codings.

Read the table by role. The signal and Ethernet codings (A, B, D, X) carry low currents — a few amps at most, and as little as half an amp on the high-speed Ethernet codings, because their job is data and sensor signals, not power. The power codings (T for DC, K for AC, plus legacy C) jump to 12–16 A and up to 630 V, because their job is distributing supply. The same 12 mm M12 body therefore spans a very wide electrical envelope depending only on the coding you choose.

Rated Current

Rated current is the continuous current each contact can carry. On M12 connectors it ranges from about 0.5 A on the Ethernet codings to 16 A on the K-coded AC power connector. Two factors drive it:

• Coding/role. Signal codings need only enough current for sensor supply and switching; power codings are built for supply distribution, so their contacts and spacing are larger.
• Pin count. As pin counts climb on a fixed 12 mm body, the individual contacts get smaller, so the current each contact can carry falls. This is why a high-pin-count signal connector has a lower per-contact rating than a low-pin-count one, and why you should always check the rating of the specific part rather than assuming a family maximum.

Pick a connector whose rated current sits comfortably above your steady-state load, not exactly at it, to leave thermal margin.

Rated Voltage

Rated voltage spans 50 V to 630 V across the M12 range. Ethernet codings sit at the low end (around 50 V) because they carry data, not power. Signal A-coding typically falls between roughly 60 V and 250 V. The power codings reach the top: DC power (T) is around 63 V, while AC power codings (S and K) are rated up to 630 V. As with current, the figure follows the coding's role, so confirm both the voltage class (and whether it is AC or DC) for the specific part.

Operating Temperature Range

M12 connectors are typically rated for −40 to +85 °C, with some parts rated −25 to +85 °C. That wide range is one reason M12 is used across factory floors, outdoor installations and mobile equipment. The limiting factor is usually the housing material and the attached cable rather than the contacts, so for extreme heat, cold or thermal cycling, confirm the rating of the connector and its cable against their datasheets.

Ingress Protection (IP Rating)

Sealing is a defining M12 feature. Connectors in the range are commonly rated IP67, with IP68 (continuous immersion) and IP69K (high-pressure, high-temperature washdown) options for harsher environments. Two rules matter regardless of the figure: the rating only holds when the connector is mated and tightened to torque, and unused ports must be capped, because an open port has no protection at all. For the full breakdown of what each IP digit means and when to choose IP67 versus IP68 or IP69K, see the IP rating guide.

Mating Cycles, Contact and Insulation Resistance

A few smaller specifications round out the picture:

• Mating cycles — M12 connectors are typically rated for at least 100 mate/unmate cycles. Industrial connections are usually made once and rarely disturbed, so 100 cycles is ample for normal use.
• Contact resistance — low (on the order of a few milliohms) so the connection does not waste power or generate heat under load.
• Insulation resistance — high (on the order of hundreds of megohms or more) so current stays in the contacts and does not leak between them, which matters most on the higher-voltage power codings.

These figures rarely drive a selection on their own, but they confirm the connector is fit for a sealed, long-life industrial connection.

Connector Rating vs Cable Rating

A specification trap worth highlighting: the figures above are the connector's ratings, but a cordset or cable assembly is only as good as the weaker of the connector and the cable. A connector rated for 16 A delivers 16 A only if the attached conductor gauge can carry it; a thinner conductor lowers the effective current of the whole assembly, and a longer run adds voltage drop that matters most on low-voltage DC power. The same applies to temperature and sealing — the cable jacket's temperature class and the cable gland's IP rating can cap an assembly below the connector's headline figure.

The practical rule is to specify the assembly, not just the connector: match the conductor cross-section to the current, the jacket to the temperature and chemical environment, and the overmould or gland to the IP rating you need. When you order a pre-moulded cordset this is handled for you, since the connector and cable are validated together; when you build a field-wireable assembly, you are responsible for keeping the cable's ratings at or above the connector's. This is why two connectors with identical datasheets can perform differently once cabled — the assembly, not the connector alone, sets what reaches the device.

How to Read M12 Specifications for Selection

Put the specifications together in a short sequence when choosing a part:

1. Start from the coding/role — signal, fieldbus, Ethernet or power — because that sets the broad electrical envelope. See the M12 connector types guide for choosing the coding.
2. Match current and voltage to your load with margin, checking the rating of the specific part and pin count, not a family maximum.
3. Confirm the environment — temperature range and IP rating for where the connector lives.
4. Check the mechanical fit — pin count, gender, mounting and cordset format.

To filter the range against these parameters interactively, use the connector selector; for the broader introduction to the M12 standard, see what is an M12 connector.

Key Takeaways

• M12 specifications follow the coding's role: signal/Ethernet codings are low current/voltage, power codings (T, K) are high.
• Rated current spans ~0.5 A (Ethernet) to ~16 A (K-coded AC); rated voltage spans 50 V to 630 V.
• Per-contact current falls as pin count rises, so always check the specific part, not a family maximum.
• Connectors are typically IP67 (IP68/IP69K available), rated −40 to +85 °C, and good for at least 100 mating cycles.
• Always confirm the exact figures against the part's datasheet before specifying.

Frequently asked questions

What is the rated current of an M12 connector?

It depends on the coding and pin count. Signal A-coded connectors are typically rated around 1–4 A, Ethernet D- and X-coded connectors as low as about 0.5 A per contact, and power codings such as T (DC) and K (AC) up to about 12–16 A. Always confirm against the specific part's datasheet.

What voltage can an M12 connector handle?

M12 rated voltage ranges from about 50 V on Ethernet codings up to 630 V on AC power codings. Signal A-coded connectors typically fall between roughly 60 V and 250 V, while DC power (T) is around 63 V and AC power (S, K) reaches 630 V. The rating depends on the coding.

What is the operating temperature range of M12 connectors?

M12 connectors are typically rated for −40 to +85 °C, with some parts rated −25 to +85 °C. The exact range depends on the housing material and cable, so confirm it against the datasheet for demanding environments.

What IP rating do M12 connectors have?

M12 connectors are commonly rated IP67, with IP68 and IP69K options for immersion and high-pressure washdown. The rating only holds when the connector is mated and tightened to torque; unused ports must be capped to keep the sealing.

How many mating cycles is an M12 connector rated for?

M12 connectors are typically rated for at least 100 mating cycles. That is ample for installations that are connected once and rarely disturbed, which is the normal case in industrial wiring.