Lightning Protection

[David006]

Just reading a thread re protecting electronics from surges induced by lightning...so went to google and found essentially that there is enough of significant delay (to electronics) in operation of VOM type protection and even gas or air gap protection to affect electronic equipment.

Seems the only sure way to protect all your STUFF may be to unplug it. ..So then I thought about a mate in a Singapore marina had all his electronic gear go tits up by a lightning strike not in the immediate vicinity...with no shore power connected....maybe it was electromagnetic induction? One article on google mentioned that EMI can come out of a clear blue sky!

Comments?? ....if you have nothing better to do..lol

edit: oops meant MOV not VOM...

Edited August 6, 2010 by David006

[electau]

Install surge protection device at the main switchboard, protect with an MCB. Install after the main switch and before any RCDs.They should be rated at 275V and an impluse level of 8/20 microseconds.

Use a surge protected power board for your electronics. The socket outlets should be earthed.

　

[stgrhe]

This is an example of what electau is talking about, surge protectors in the distribution board. In this case it is a three phase DP, hence the need for more than one. My DP is not yet commissioned and the surge protectors are from the German company Dehn + Schöne, a specialist company in this particular field.

http://www.dehn.de/

[bankruatsteve]

Surge suppression via MOV device (or other more sophisticated/expensive) should handle most indirect lighting. However, there are many examples/stories of direct strikes where it doesn't matter what you have in place. Yeah, unplugging is the only mostly sure way in that case.

[Crossy]

Surge suppression via MOV device (or other more sophisticated/expensive) should handle most indirect lighting. However, there are many examples/stories of direct strikes where it doesn't matter what you have in place. Yeah, unplugging is the only mostly sure way in that case.

Agreed, pretty much nothing will save your kit from a direct hit on your power / phone line, this is however a relatively rare event.

Good quality MOVs correctly installed will mitigate most indirect events, but you need protection on all incoming wiring (don't forget the phone line) using decent devices.

[stgrhe]

Agreed, pretty much nothing will save your kit from a direct hit on your power / phone line, this is however a relatively rare event.

Good quality MOVs correctly installed will mitigate most indirect events, but you need protection on all incoming wiring (don't forget the phone line) using decent devices.

In my installation, referred to in my earlier post, I will have surge protectors also for the telephone lines as well as for the satellite antenna cable. They are also from Dehn and are rated 10kA and 2.5kA respectively whereas the surge protectors for the power line are rated 40kA.

[Crossy]

Agreed, pretty much nothing will save your kit from a direct hit on your power / phone line, this is however a relatively rare event.

Good quality MOVs correctly installed will mitigate most indirect events, but you need protection on all incoming wiring (don't forget the phone line) using decent devices.

In my installation, referred to in my earlier post, I will have surge protectors also for the telephone lines as well as for the satellite antenna cable. They are also from Dehn and are rated 10kA and 2.5kA respectively whereas the surge protectors for the power line are rated 40kA.

With that lot I reckon you'll be protected from a nuclear strike

Do Dehn have a Thai agent who'll supply small quantities? How did you obtain your kit?

Any thoughts on protection on network cables (we'll probably be installing CAT6)?

[stgrhe]

With that lot I reckon you'll be protected from a nuclear strike

I wish that was true, but due to budget constraint I have had to postpone the outer shield with lighting arrays and separate earthing.

Do Dehn have a Thai agent who'll supply small quantities? How did you obtain your kit?

Yes, they are available locally here in Thailand through PMK, the company in Nonthaburi that produced my DB. PMK is also the main distributor for ABB here in Thailand and one of the very few real professional companies I have come about here.

http://www.pmk.co.th...w&id=4&Itemid=5

Any thoughts on protection on network cables (we'll probably be installing CAT6)?

I have been thinking about it but since our house construction budget is already burst this has had to be shelved for the time being. Eventually I will need some kind of protection for the LAN that run between the main house and our guest house.

Also, since we now plan to install two satellite discs, one for Astro (Ku-band) and one for some Thai crappy channels (C-band), I need to get a second surge arrester (Dehn Gate GFF TV as it is called) for the second coax. They cost 6,000 baht plus VAT.

The telephone arrester is of the yellow line called Blitzductor [bXT ML4 B 180 10KA (10/350) + BXT BAS], a plug-in unit, and costs 13,100 baht plus VAT. For the four voltage arresters [Dehn's red line type DG M TT 275 40kA (8/20)] I paid 13,500 baht plus VAT.