Overvoltage is a physical phenomenon which, for various reasons and from time to time, occurs and spreads in electrical systems. The most common causes of overvoltage can be divided into:
- Atmospheric overvoltage during storms
- Overvoltage resulting from the discharge of static electricity
- Transients caused by switching on and off
- Transients occuring in the case of failures
Considering the damage overvoltage can cause to electronic devices, it is necessary to prevent it using overvoltage protections, especially in outdoor and industrial installations. For this reason, the ports of the devices developed and manufactured in METEL are by default protected from overvoltage and the level of the protection is scaled in order to reflect expected deployment of the device:
Fast Ethernet Ports for outdoor installations: 1000A current wave 8/20 µs
Fast Ethernet Ports for indoor installations: 30A current wave 8/20 µs
Gigabit Ethernet Ports: 30A current wave 8/20 µs
Supply Inputs 10-60VDC: 30-100A current wave 8/20 µs
For testing strength and durability of our devices we use the following standards:
EN 61000-4-5,
Is suitable for testing of devices resistance to low-energy pulses, levels of low electromagnetic interferences.
EN61643-11,
Which is generally used for the testing of overvoltage protections, i.e. testing of resistance to high-energy pulses and therefore very closely simulating actual overvoltage levels, expecially during storms.
The result of this intensive testing procedure are effective port overvoltage protection, positively affecting the reliability of our products. They also contribute to our devices achieving extremely high levels of failure-free operations expressed by higher values of MTBF (Mean Time Between Failures). In order to provide the maximum, unbiased view, we calculate MTFB using the reliability of the operation of the devices sold, according to the formula: MTBF=H/F where H=the total number of running hours of all switches sold and F=the number of failures.
This provides our customers with a reliable overview of the quality of our devices. It should be kept in mind that the MTBF is not only affected by the quality of the device itself, but also by the quality of the supplied documentation and technical support provided to customers.
Another, frequently used method of calculating MTBF is calculating the expected MTBF using the reliability of individual components. The main downside of this approach is that it is only an assumption, not taking into account e.g. the occurrence of overvoltage in the real operation of the device.
The selected MTBF calculation approach also provides valuable information for continuous improvements of our devices quality, in accordance with the certified quality system ISO 9001:2009.
Current MTBF values can be found HERE.
Which specific benefits do our products with integrated overvoltage protections provide?
- Significant savings of system service costs
- 5-year guarantee , covering all aspects of the devices.
- High safety and reliability of the operatation system.