3 Steps to Selecting M8 and M12 Cordsets

Thirty years ago most industrial control systems (ICS) were hardwired. Often sensors and actuators came with long wires already attached or individual wires that weren't even jacketed together. Those wires would be threaded through conduits and then wired into the system. This was a time-consuming process that required the services of an electrician, costing organizations significant time and money.

The Hannover Fair of 1985 changed all that. M12 connectors were introduced and they stole the spotlight. Incorporating the use of the smaller M12 metric thread, they were initially released in 3-and 4-pin versions, with an IP67 rating. The M8 hit the market four years later, and soon both formats were standardized under IEC 61076-2-101, making them the standard for ICS.

A system that is linked up with M12 and M8 connectors makes assembling, testing and servicing ICS faster and less expensive. These advantages are further enhanced when a cord set is used instead of installing separate cables and connectors. Let's take a close look at the advantages of M8 and M12 cord sets and the steps needed to select the right one.

How to choose the right cord set?

1. Start with the Environmental Needs

The possible combinations of cables and connectors is a surprisingly high number. Where do you even start the specification process?

Like most engineering decisions, there’s a balance between cost and performance. You want to choose the lowest cost option that meets the requirements of the application. For example, you don’t need armored cable if it is going to be run in wire trays in a temperature- and humidity-controlled environment.

Thus the first question to ask yourself is “How harsh is the environment for my project?” The answer to this leads to selecting the right industrial cable jacket and the right IP rating for the cord set.

2. Determine the Connector Configurations

Since the introduction of the 3- and 4-pin versions of the M12 connector, many more variations and options have become available. While 4-pin M12 connectors are the most common, be sure to analyze your application and choose from:

straight or right angle configurations

3-, 4-, 5-, 8- and 12-pin versions

For M8 connectors your options are:

Straight or right angle configurations

Snap(IP65) or screw connection (IP67)

3-, 4- and 8-pin versions

3. Select the Keying Options

The M12 connector is also available in a variety of keying/coding options to further minimize wiring errors as follows:

A-code – Primarily used with sensors and actuators

B-code – PROFIBUS fieldbus connections

C-code (dual keyway) – Primarily used with AC sensors and actuators

D-code – 100Mb EtherNet/IP 4-pin

X-code – Gigabit Ethernet 8-pin

The following M8 connector configurations feature a keying/coding*:

B-code – PROFIBUS fieldbus connections

8-pin version

Improve Reliability with the Right M8 or M12 Cord Set

The right cord set reduces installation time, wiring errors and machine start-up time.

To select the best value cord set, carefully identify the harshness of the environment. Then select the appropriate cable shielding and cord set that will do the job.  There is no point in paying for a wash-down cord set for a material handling application.

Next specify the connector configuration(s) and, in the case of the M12 connector, the keying option(s).

Once production begins, if a sensor or actuator needs to be replaced it can be done quickly, minimizing expensive downtime. Your operation will benefit from maximum dependability and performance.