M8 vs M12 Connector , What is Difference ?

M8 connector and M12 connector are both waterproof circular connector which could be used for sensors, actuators, automation, industrial ethernet , robots and other application, the main difference is the size, locking thread, coding type, pin quantity, and application.

There are waterproof circular connector that have both M8 and M12 interface, like M8 to M12 adapter , M12 to M8 cable, we can call them M8 connector or M12 connector.

What is an M8 connector

The M8 connector is a type of electrical connector commonly used in industrial automation, robotics, and sensor applications. It has a circular shape with a connecting diameter of 8mm, hence the name M8. The connector typically has 3-pin, 4-pin, 5-pin and 8-pin, coding types as A-coded, B-coded, D-coded.

M8 connectors are designed to be robust and reliable, with a high degree of resistance to vibration, shock, and moisture. They are typically used in harsh environments where other types of connectors might fail. The connectors are available in various styles, including straight, angled, and panel-mount configurations, and they can be wired with either a screw or spring terminal.

M8 connectors are used to connect sensors, actuators, and other devices in industrial automation applications. They are also commonly used in the automotive industry, as well as in the field of process control and instrumentation.

Types of M8 connector

5 important things need to know before purchasing M8 connectors

1）What types the M8  connector：First of all, we need to what M8 connector will you, prewired(shielded or unshielded) , field wireable(metal or PA66 shell) , bulkhead connector(front or back mount, PCB mount), or splitters, coding types, male or female, straight or right angled, pin quantity.

2) Electrical parameters of the M8 connector: The current-carrying capacity of the M8 connector is very important, and will determine the application it suits. Due to the small size of the M8 connector, more  pins, the smaller of the current-carrying capacity. Usually, The 3-pin M8 connector has a higher current rating than the 8-pin M8 connector. If the rated current of the M8 connector does not meet the requirements, then you need to choose a bigger size connector, such as the M12 connector. The M8 connector is more suitable for applicaitons with small current and size requirements

3) The size requirements of the M8 connector in the installation environment: whether the M8 connector can be used, depends on the  installation space, if the height is enough, and if the width is enough, straight or angled type will be used accord to the space, if the space is too small,then we have to consider much smaller connector.

4）Different environments have different requirements for M8 connectors: some M8 connectors are not designed waterproof, vibration-proof or corrosion-proof, so they cannot be used in harsh environments. For example, snap in M8 connectors are not suitable for severe vibration or in applications with high waterproof requirements, in very harsh environments, metal connectors will perform better than plastic connectors.

5）Service life of the M8 connector: After being installed on the device, some connectors may not change or disconnect for a long time. If they work in a long-term water, gasoline or vibration environment, will these affect the protection level of the connector? Whether the reliability of the device connection will be affected because the design life of the connector does not meet the requirements, these are issues that need to be considered.

What is M12 connector ？

The M12 connector is circular waterproof connector with locking 12mm thread , and it can at least reach IP65 protection level to prevent liquid or dust from affecting the reliability of the connection. M12 connectors are widely used in connection solutions for sensors, actuators, and industrial Ethernet and fieldbus devices, and can be used in harsh environments and even corrosive environments in industrial automation.

As the most popular and classic connector, the M12 connector has been used in automation for a long time. It was originally a 3-pin or 4-pin connector, which evolved from the RK30 connector. It is not as good as the RK30 in terms of electrical performance. , but the protection level is much better, which can reach IP67 waterproof. 4-pin M12 connector outlet to meet the needs of more complex industrial sensors. Because the design of the M12 connector is so classic and loved by the majority of engineers, the M12 connector has been continuously developed into 5-pin, 6-pin, 8-pin, 12-pin and 17-pin, as well as a wealth of locking methods and coding types, further expanding the application in industrial automation.

Types of M12 connector 

The standard thread of the M12 connector is 12mm. The reliable protection of the connection is achieved by locking the male plug or socket with the thread of the female plug or socket. The protection level reaches IP67 which suit for harsh industry application, usually have 2pin 3pin 4pin 5pin 6pin 8pin 12pin 17pin male connector or female connector, can be straight or angled. M12 connectors have 2 types , overmolded with cable, or field wireable type without cable. PVC material for the cable is used mostly , and for some with higher requirements will choose PUR (oil-resistant and wear-resistant) material.The length of the cable is made accord to customer requirements. Some applications for signal or data transmission with high requirements will require shielding. If the requirements are not high, you can also choose unshielded M12 connector.

The M8 connector is smaller than the M12 connector. It uses an 8mm thread. The male and female are also connected by tighten the thread to achieve the waterproof function. The highest protection level can reach IP67, and there are also conventional IP65 protection levels. Usually there are 2 pin, 3 pin, 4 pin, 5 pin and 8 pin M8 connectors,  they are available in straight or right angeld type. There are also PCB type sockets. Fast and convenient for on-site maintenance. The cable material of the molded M8 connector is also made of conventional PVC material and PUR material with better oil resistance.

1. Different sizes : M12 connector is bigger than M8 connector, M8 connector have male or female 3-pin 4-pin 5-pin 6-pin 8-pin for option; M12 connector has male or female 2-pin 3-pin 4-pin 5-pin 6-pin 8-pin 12-pin 17-pin, M12 connector have more pin options.
2. Locking thread : M12 connector has 12mm, M8 connector has thread 8mm.
3. Same point : Both are circular waterproof connector that can be straight or angled,which can be plug or socket,all have cable assembly type without cables and molded ones with cables,all have PVC PUR material cable for option.
4.  Pinout : M12 connector pinout and M8 connector pinout are different, M12 connectors have more coding types and pin arrangement than M8. 
5. Electrical parameters : compared with same pin for A coded, M12 use thicker conductor than M8, will have higher voltage and rated current.
6. Connector types : M12 have more types than M8, as M12 is the most widely waterproof connector and have bigger size, it’s available for more types, for example M12 is available for more splitter types.
7. Application：The application fields of M8 and M12 are very similar, and they had been widely used in the field of automation, such as equipments, instrumentation, electrical systems, sensors, actuators, etc.

M8 and M12 connectors are designed for harsh industrial environment applications, so they both have a very high level of protection class.

The M8 and M12 connectors produced from different manufacturers looks very similar,but materials, electrical performance, protection class can be big difference,even some products cannot meet the requirements of industrial application. Users should choose the ones with good reputation, rich experience in the industry, and large scale, famous brand connector manufacturers, this will reduce failure rates and reduce maintenance costs

Tips  to Choose M12 Connector 2 3 4 5 6 8 12 17 Pin

1）Application requirement : First the user should confirm the application requirement and choose the suitable model. M12 connectors are available in many different models, coding types, and are designed to suit different application environments from the very beginning. Therefore, in the selection process, it is necessary to compare the parameters of different M12 connectors, confirm the current, waterproof level, coding type, number of cores, installation space and other information, and finally make a reasonable choice according to the environment and application requirements.

2）Reliable manufacturer : Choose a manufacturer with more influence and strength. Although have  same industry standard, different manufacturers will have different quality implementation standards during production. Under normal circumstances, manufacturers with brand influence tend to have a lower defective rate. In the selection process, the user must take into account the product differences brought by different manufacturers and brands, fully consider various factors such as price and risk, and make a comprehensive evaluation to make a choice.。

3）Materials : Materials of the M12 cable connector, the material is very important to realize the technical parameters and protection level of the connector, such as contact pins normally are gold plated brass, brass have very good electrical performance, but it is easily oxidized in the air, gold plated process ensures the conductivity while avoiding oxidation, and the size and contact area of the pins will affect the current carrying capacity, the material of the connector shell will affect the protection performance in harsh application environments, the accuracy,size error, will also affect the protection level

4）Stability : Stability of data, power or signal transmission. The M12 connector itself is a connecting device. If the signal or power transmission is unstable, or the carrying capacity is insufficient, it will cause problems in the entire system. The main things to consider here are the current carrying capacity, shielding function, and protection level, such as data and signal transmission must have a shielding function, otherwise the signal will be interfered, and the power transmission must consider the current carrying capacity, otherwise the equipment will not operate normally, and the anti-vibration function must be considered in the vibration environment, and the vibration may cause the connection to be interrupted.

5）Quality : The failure rate of the M12 connector. Because the connector is a very small part of the automatic control system, it only serves as a connection and is not the core component of the system. However, because of a small component, the whole system will have problems and affect the production operation, which is very worthwhile. , so be sure to choose high-quality products with low failure rate。

6）Harsh environment tolerance ： Comparison of waterproof performance. In outdoor and industrial environments, various factors such as water vapor, oil pollution, high temperature, acid and alkali may affect the reliability of the connection. If sufficient possible protection is not achieved, water and gasoline pollution will enter the connector and damage the contact. The connection will be  unstable or interrupted.

M12 connector application

M12 connectors are widely used in industrial automation and control applications. These connectors are designed to provide a reliable and robust connection for sensors, actuators, and other devices in harsh environments. M12 connectors come in a variety of configurations, including A-coded, B-coded, C-coded, D-coded, X-coded, S-coded, T-coded, K-coded, L-coded, and M-coded. Each configuration is designed to meet specific application requirements.

Sensor and actuator : M12 A coded 3-pin, 4-pin, 5-pin had been used a lot for sensor and actuatoras in automation.

• Data tranmission : M12 A coded 6-pin, 8-pin, 12-pin, 17-pin could be used for data transmission, and for data transmission mostly will need shielded cables.
• Industrial ethernet : M12 A coded 8 pin, D coded 4 pin, X coded 8 pin and Y coded 6 pin 8 pin could be used for high speed industrial ethernet.
• Small power supply : M12 A coded and C coded connector can be used for power supply connector.
• Big power supply : M12 S coded, T-coded, K-coded, L-coded, M-coded connector had been adopted as DC or AC big power supply for lots of applications.
• Machine vision : M12 A-coded, D-coded, X-coded connector are widely used for machine vision cameras, A coded cable can also be used as I/O cable.

Difference between M12 cable, M12 field wireable connector, M12 bulkhead connector

The difference between M12 molded cable, M12 field wireable connector, and M12 bulkhead connector is in their design and application.

M12 molded cable: This type of connector is a pre-made, ready-to-use cable with an M12 connector on one end and a specific termination on the other end. The cable is typically molded onto the connector, making it a single, integrated unit. M12 molded cables are commonly used for connecting sensors, actuators, and other automation devices in industrial settings.

M12 field wireable connector : This type of connector is designed to allow for field termination of an M12 connector to a cable. The connector typically consists of a male or female M12 connector, a backshell, and a cable gland. The cable is stripped and wired directly to the connector, and the backshell and gland provide strain relief and environmental protection. M12 field wireable connectors are commonly used when the cable length or termination type needs to be customized in the field.

M12 bulkhead connector : This type of connector is designed to be mounted to a panel or bulkhead and provides a sealed connection between two M12 connectors on either side of the panel. The connector typically consists of a male or female M12 connector, a mounting nut or flange, and a sealing gasket. M12 bulkhead connectors are commonly used when an M12 connection needs to be made between two areas that are separated by a panel or bulkhead.

In summary, M12 molded cables are pre-made cables with an M12 connector, M12 field wireable connectors allow for field termination of an M12 connector to a cable, and M12 bulkhead connectors provide a sealed connection between two M12 connectors on either side of a panel or bulkhead.

M8 To M12 Adapter

M12 to M8 Cable

M12 to M8 cable is one end M12 connector, one end M8 connector, each end can be male or female, if the M12 connector split in to two or more M8 connectors, it can also be called M12 to M8 splitter.

M12 To M8 Splitter Cable

Do you find out the difference for M8 and M12 connector ? If you have more questions, welcome to contact us.