How to choose an industrial Ethernet switch?

What is an industrial switch?

An industrial switch is also known as an industrial Ethernet switch. Industrial Ethernet switches are mainly for real-time Ethernet data transmission in complex industrial environments. Standard Ethernet is not designed with the application requirements of industrial networks in mind. Therefore, when the network equipment is deployed in industrial fields, the stability of standard commercial switches will be significantly challenged by the harsh working environment and severe electromagnetic interference, which will reduce and their reliability.

Therefore, industrial Ethernet switches with high reliability, stability, and security have emerged as transmission devices that can adapt to complex industrial environments and facilitate the deployment of industrial automation networks.

Because industrial switches can withstand harsh working environments, have a wide range of products and flexible port configurations, they can meet the needs of various industrial control fields. With the rapid development of electric power, metallurgy, petrochemical, environmental protection, transportation, construction, and other industries, the demand for industrial Ethernet switches in the information construction of various sectors is also increasing.

Commercial Switch vs. Industrial Switch, What is the difference?

• Industrial grade components: Industrial switches require high features like industrial transceivers to withstand harsh environments. They are well suited to industrial-grade environments and support industrial applications in harsh environments.
• Fast ring and redundancy: Industrial switches generally have a fast ring, fast redundancy, system redundancy time can be less than 50ms, although commercial products can also form a redundant network, the self-healing time of 10-30s more, can not meet the use of the industrial environment.
• Super anti-interference performance: Industrial switches have anti-interference solid performance and can work in harsh electromagnetic environments, and have high protection levels in lightning, water, corrosion, shock, and static protection, which are not available in commercial switches.
• Wide Operating Temperature: Industrial switches generally use metal shells for better heat dissipation, dustproof and anti-corrosion, IP30 protection level, and can typically work in the temperature range of -40℃ to +75℃, which can well adapt to the complex temperature and humidity. Commercial switch products can only work in the field of 0℃-+50℃, which can not meet the requirements of the harsh climate environment.
• Redundant power supply design: Power supply is a vital part of industrial switches. To avoid the trouble caused by power failure, industrial switches adopt a dual power supply redundancy design to ensure the stable and reliable operation of the system. Commercial products generally use a single AC power supply, which is unsuitable for industrial environments.
• Long life: Industrial switches use industrial-grade solutions from housing materials to supporting components, so they are more reliable and have a longer service life, generally >10 years, compared to 3-5 years for ordinary commercial switches.

How to choose the right industrial switch

The industrial field environment is harsher than any ordinary environment, at least in vibration, humidity, and temperature. Regular switches are not for withstanding the various conditions in industrial environments. The reliability of industrial switches includes:

• Power failure.
• Port interruption.
• Alarm by relay output.
• Redundant dual DC power inputs.
• Active circuit protection.
• Over-voltage.
• Under-voltage automatic circuit break protection.

In general, you can focus on the following aspects.

• Normative: The selection of industrial switches should meet industry specifications, such as risky occasions, to choose products that meet the corresponding certification specifications; rail transit industry to choose products approved by the rail transit industry.

• Reliability: In an industrial field environment, reliability is critical. The main factors related to product reliability are the tolerance of the equipment hardware to the working environment: operating temperature range, EMC electromagnetic compatibility, lightning protection level, installation and power supply method, fanless design, redundancy method, fault diagnosis, and recovery capability, etc. In the parameter description of the product, there should be a detailed description of the operating temperature range, EMC protection, and lightning protection level.

• Real-time: Network data transmission generates an inevitable delay, so the first thing to consider when selecting an industrial Ethernet switch is the port delay during data frame forwarding. The system can tolerate a response time of no more than 10 milliseconds in a standard factory automation control system. Therefore, it is essential to note that the switch port latency should not exceed 10 microseconds when selecting a switch.

• Compatibility: Industrial Ethernet switches and other Industrial Ethernet components should communicate using the standard TCP/IP protocol. In any case, there should be no incompatibility between industrial Ethernet devices and commercial Ethernet devices. The industrial Ethernet devices should be compatible with different industrial Fieldbus solutions.

Final Words

Besides, in choosing industrial switches, users should also select appropriate twisted pair or fiber optic interfaces according to some basic requirements such as transmission distance and transmission bandwidth. PoE Power over Ethernet switches can be used for wiring convenience when connecting some devices such as video terminals and wireless base stations. If the network is relatively simple, you can choose a plug-and-play unmanaged switch; if it is convenient for future maintenance, you may need to select a managed type. Only a managed switch can achieve a ring-type topology connection.