This man is an amazing master in his job. With his help, through online consultation, we repaired two 5KV UPS controller board. . Only after describing the problem, he immediately showed us the damaged part... Now both of UPS working like a new. Lots of thanks and recommendations from me. I want everyone who has had problems with UPS devices, to know about him. He has an expert knowledge. That's why I write this comment on all his videos. I spent 4 nights without sleep looking for the problem. 👍 👍👍