Can 220V gadgets be damaged by 1200Vac VPR @8/20 µs SPD?

[kolei]

Can the RS-50-24 (and the computer board etc. it supplies) in the following be damaged by a 1200 volts passing through it at 8/20 µs? This VRP value is the typical voltage protection rating of an SPD type II surge protector after it's done it's job.

https://www.meanwell.com/webapp/product/search.aspx?prod=RS-50

The surge protector specs are exactly:

Thank you.

 

[Skogsgurra]

Usually, the fast 8/20 us transients do not get as far as to the input of a power supply. There are inductive components in cables and there are coils in protective gear that keeps it back. The cable capacitance also helps.
Add to that that there is an EMC filter on the input and that reduces the transient further.

My thinking is that the PSU can survive also without extra protection. And, if you add the MOV specified, there should not be any problem whatsoever. Are you having a case where you think that a (lightning) transient has killed equipment? There is, as you can see in the block diagram, total isolation between input and output and that isolation has been tested with 3 kV AC, which translates to a 4+ kV 1 ms peak. So, if you have a problem with attached boards, it can probably not be the PSU that causes it. Electro-static discharge seems a lot more probable.

Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[waross]

Hi Gunnar. Isn't lightning form of electro-static discharge?
We have lost our wireless internet modem/adapter several times when there were lightning discharges miles away.
We installed an APC UPS/Surge suppressor and have only lost two modems since.
Fortunately the service provider has run out of old stock and the latest replacement has much better protection.
It must have been a very poor design, and I suspect that the roof mounted antenna was directing a surge into the back door of the modem where surges were not expected. We never lost any other equipment during a storm, just the modems.
I agree completely that not much gets through the distribution transformer and the cables.
One time I phoned in and the girl asked my what I thought the problem may have been.
I mentioned that it may have been a lightning storm.
"I'm sorry. We don't give warranty coverage for lightning damage."
"Just a minute. I don't know what caused the damage. You asked me what I though and I made a guess but I have no way of knowing for sure."
"Please hold. I have to speak to my supervisor."
A short time later.
"We will be sending you a replacement modem at no charge."
I learned.
The next time we lost a modem about the time of a storm.
"I have no idea what happened. It just stopped working." It was much safer. Let them prove that it was not lightning.
The point is, to agree with you, the power circuit protections are pretty good, but an electro-static discharge where it is not expected, whether body discharge from a finger or a lightning induced discharge through the back door, bypassing the protection circuits can get you.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Skogsgurra]

Hello wise guy. You know what I mean.

Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[waross]

I was agreeing with you Gunnar. Not much of a static discharge gets past the protection on the supply side.

Bill
--------------------
"Why not the best?"
Jimmy Carter