Video recording of the webinar "Answers to questions about surge protectors"

Dear friends!

Last Wednesday, 10 February, the eleventh webinar with professor Eduard Meerovitch Bazelyan took place. The main part of the webinar was a Q&A on the selection and usage of surge protection devices (SPD). Questions were received from designers in advance and passed on to the professor. Answers to these and other questions can be found in the video:

  • Is there any sense in having external lightning protection without SPDs and SPDs without external lightning protection? (time 39:19)
  • Is there any danger connected with the use of SPDs or usage limitations? (time 43:15)
  • Does grounding resistance matter when choosing/operating an SPD? (time 44:32)
  • For which grounding systems it is correct to use a SPD with a 2+0 (4+0) or 1+1 or (3+0) connection scheme between the poles? (time 46:25)
  • Does it make sense to install SPDs of one class or is a set of SPDs from different classes required? (time 48:23)
  • How effective are class 1 and 2 SPDs compared to a separate installation of SPD1 and SPD2? (time 49:55)
  • How to choose a safety device for an SPD circuit correctly? Is a safety device necessary? (time 51:00)
  • The power cable enters the distribution board in the garage. A house with installed lightning protection is located 40 meters from the garage and also has a distribution board. Which SPD classes must be installed and where? (time 56:12)
  • Are there any external factors that can negatively influence the stable operation of an SPD? (time 57:49)
  • What is the is the probability of SPD malfunction if it chosen and operated correctly, excluding any manufacturing defect? What could be the source of such a malfunction? (time 59:09)
  • How can the functionality of an SPD can be checked if there is no indicator? (time 59:57)
  • Is there any fundamental difference between the methods for SPD selection in the Russian and European standards? (time 1:00:46)
  • Is it not easier to protect equipment with SPDs in an existing building or small facility, for example, a single-family house, than with shielding down conductors? How can an ordinary person (not an engineer) estimate electromagnetic impact? (time 1:02:00)
  • Has the map of thunderstorm activity changed? (time 1:06:10)
  • What manufacturer writes the requirements for fuse links? (time 1:09:00)
  • A surge protector is installed in a transformer substation on the high and low sides; we install fuses on the 0.4 kV side. On the 6-10 kV side, we connect a surge protector directly to the buses without any switching devices. Is this a violation? (time 1:13:24)
  • Is there a general recommendation for the nominal current of a fuse link, for example 20A, instead of calculating it? (time 1:19:29)
  • Fire safety of variable resistor SPDs on thermal breakers built into SPDs (time 1:22:40)



Do you have any questions left about SPD usage? Please send it to us, we will help you solve them!