Industrial Automation Runs on M Series Sensor Connectors

Connectors carry power, signals, and data between electronic components in a system. Among these, the circular M Series Sensor Connectors from Amphenol LTW are popular options widely used across a range of industrial applications.

These connectors are available in various forms (Figure 1) and comply with IEC 61076-2-105 and 61076-2-104, which define standardized locking mechanisms for circular connectors. Compliance with these standards ensures that the M series connectors are mechanically and electrically interchangeable with similar products, enhancing design flexibility and simplifying integration.

Amphenol LTW’s sensor connectors are also more compact, lightweight, and cost-effective than traditional four-pair Ethernet cables, making them well-suited for modern Industrial IoT applications.

Figure 1: The M series includes receptacles, overmolded connectors with a cable, and field-installable connectors. (Image source: Amphenol LTW)

Why the M series is a good fit

The M series consists of metric connectors, including M5 for small sensors with low-power and low-signal needs; M8 to M12 and M16 for signal relays, and M23-M40 for power transmission. The numerator refers to the diameter, so for example, the M8 connectors have 8 mm diameter fasteners, while M12 connectors have 12 mm diameter fasteners.

M8 and M12 A-coded connectors are specifically intended for sensors. Both M8 and M12 are also available B-coded for fieldbus networks. Additionally, M12 connectors are available with:

• X-Coding for 10 Gb Ethernet
• L-Coding for low-voltage DC power
• S-Coding for AC power supply
• K-Coding for higher voltage AC power

The M series offers many advantages, which include:

• Strong and secure locking mechanisms: The circular connectors stay in place with robust threaded or bayonet-style locking mechanisms that are resistant to loosening from vibration, making them suitable for industrial automation systems or automotive applications.
• Decreased clutter: The M series can transmit data, power, and signals through a single interface, reducing the number of separate cables needed and enabling more compact system layouts.
• Durability and performance: Overmolded and IP-rated connectors offer resistance to dust, moisture, chemicals, and mechanical stress, making them suited for rugged conditions found in industrial or outdoor environments.
• Ready compatibility for multiple applications: M8 A-coded connectors are available in 3, 4, and 5 pins, while M12 comes with those configurations as well as 8 and 12 pins.

Sensor connectors

Amphenol LTW’s M series sensor connectors have high water ingress resistance, with waterproof ratings of IP65 or IP67-68. The series can handle a wide current range from 1.5 A to 28 A. Connectors in the series include receptacles and preassembled overmolded connectors with a cable. In addition, Amphenol offers field-installable connectors, which can withstand temperatures from -40°C to +105°C.

The M series sensor connectors have a heavy-duty shielding for performance in harsh industrial environments and can withstand vibrations from 10 Hz to 500 Hz. A minimum mating cycle of 100 facilitates easy transfer of equipment between applications.

Distribution boxes

An application will often need more than one connector to make multiple components function together smoothly, which is why the M series from Amphenol LTW also offers distribution boxes that serve as an organized connector hub.

The M Series Distribution Boxes from Amphenol LTW help streamline M8 and M12 connectors and related cables with easy pre-wired installation and centralized distribution. The M8 and M12 distribution boxes enhance system efficiency and productivity by providing diverse connectivity options.

The boxes are designed for industrial settings, such as automation, robotics, and processing facilities. They comply with REACH and RoHS regulations, which are European Union mandates for low chemicals in electronics. The durable and robust boxes have IP67-rated protection and are resilient against vibration and harsh environmental conditions.

Available accessories include waterproof caps, cord sets, cable assemblies, and field-installable configurations. They can also be customized with labels, different coding, and prewired with highly flexible cables for constantly moving applications.

The M series sensor connectors and distribution boxes in robotics and automation

The M series sensor connectors are especially useful in robotic applications for the following reasons:

• Connecting sensors and actuators: Temperature, pressure, position, and proximity sensors—just a few of the many used in robotics—need to connect to actuators, such as motors or grippers, that transform information into action. The M8 and M12 from the series are a good fit for these end-use cases.
• End effectors tooling: In palletizing solutions and other applications that need specific end effectors like suction cups or grippers, sensor connectors provide interconnections between them and the robotic arm. The M series is especially useful since it offers strong mating cycle ratings, which means the effectors can be changed rapidly depending on the application.
• Facilitates low-latency applications: Machine vision and other edge AI applications that are part of industrial automation solutions need connectors that can handle high-speed data transmission. These connectors support high-speed advanced data protocols such as Gigabit Ethernet and industrial fieldbus systems.
• Withstands hazardous conditions: Robots are often dispatched to hazardous conditions where it’s dangerous for humans to work. Such environments need connectors that can work in these extreme conditions.

Selecting the right M series sensor connector and distribution box

To pick the connector and distribution box that works for a specific application, design engineers will first need to consider the number of pins to handle the power and signal requirements.

Electrical specifications such as current and voltage requirements are also important parameters in the selection process. While all the M series sensor connectors perform well in harsh conditions, the overmolded design offers extra protection and water ingress resistance.

The M5 connectors with a 5 mm thread are designed for compact applications where the current is low, mainly for signal connections. M8 is a good fit for medium ranges that require durability, while the M12 is for exacting high-precision situations.

With the selection of an M8 connector, designers can choose an equivalent M8 distribution box such as the DB8-3A8CAB-SPS7B02 (Figure 2), for compact and lightweight applications or flexible robotic systems.

Figure 2: The M8 distribution box is a good fit for flexible robotic systems. (Image source: Amphenol LTW)

The M12 distribution box, part number DB12-5A4CAB-DPS7B01 (Figure 3), works best for industrial automation or robotic application scenarios that need higher power and durability.

Figure 3: The M12 distribution box is best used for industrial automation applications that need high durability and power capacity. (Image source: Amphenol LTW)

Conclusion

The M series Sensor Connectors from Amphenol LTW are a popular option for high-tech systems due to their superior ability to handle power, data, and signals, making them a reliable and easy choice for a whole range of advanced sensor-based applications.