Protection of Power Supplies Against Sudden Overvoltage

Panel-type power supplies, which are predominantly used in the automation and security sectors, convert voltage inputs coming from the grid into sensitive DC voltages such as 24 V and 48 V. At this point, the rate of damage that an impulse coming through the AC and DC lines will cause to the power supply is quite high, just as much as the sensitivity of systems operating with low DC voltage against impulses. Therefore, a power supply located within a system has to be replaced repeatedly due to damage records. This creates both a serious additional cost and, most importantly, interrupts sustainable production and operating principles. For this reason, we must protect power supplies and consequently the systems fed through the power supply against Lightning, Grid surges, Switching Impulses, Harmonics, and all sudden overvoltages occurring in the nanosecond range with Low Voltage Surge Arrester systems. While the concept of Power Supply Protection finds its place in many international projects, unfortunately, replacing the power supply seems more convenient in our country. In the projects where we go for inspection and survey, we insist on recommending protection modules for the AC and DC input parts of the power supplies instead of bearing the cost of constant product replacement and system damages. Thus, both the Power supply and our fed sensitive systems are taken under protection. For example, protecting the power supplies feeding the PLC in a PLC panel will ensure that a very important automation system survives against impulses directed at the panel.

A lightning impulse is a very strong impulse that speeds up under 25ns and reaches a value of 28000 Celsius. We must definitely take our precautions against this impulse. Generally, the use of Type 1 surge arresters in our Main Panels is considered sufficient; however, this protection module is not sufficient for the protection of the automation system panel. We have to provide sensitive protection at the end points with our products tested within the scope of IEC 61643-11 Standard.

Protecting power supplies inside the panel is the most important step of this sensitive protection. We can provide a Type 1+2+3 monophase or triphase 100kA protection at the 220V Supply point. The product placed in the system before this power supply will also protect the Power Supply AC Line. In addition, using 12, 24, 48V protection products according to the voltage level at the DC output will ensure the protection of both the power supply and the systems fed on this line. Especially impulses coming through power supplies located inside camera cabinets burn both the power supply and the camera system. Therefore, we absolutely must take our precautions.

In this paragraph of our article, we will reveal our solution that makes the real difference. Generally, 12, 24, 48 V sensitive system protections are in the Type 3 category. As you know, we can provide protection against lightning impulses in the B, i.e., Type 1 category. The existence of a protection value in the 10/350ms curve expresses the lightning protection characteristic. The power supply lightning protection product we will recommend to you contains Type 1, I.E., B characteristic in 12, 24, 48 V sensitive system protection. Thus, we are truly taking our sensitive systems under protection against lightning. Our DC PROTEC BR 10 series product, which is applied in series to the power supply, has been created as a result of the R&D studies of Iskra Zascite-Raycap engineers, for whom we carry out the country responsibility. You can contact the Yılkomer Lightning Protection Center technical office for detailed information and product information on the subject.

 

Download DC PROTEC C(R) 40 DataSheet

Download DC PROTEC B(R) 10 Datasheet