Surge Supression - Ethernet cables?

Old 12-11-14, 06:49 PM
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Surge Supression - Ethernet cables?

I have an Ethernet cable hooked to my modem/router to my pc for internet. The router/modem is connected with phone line.

I do not have the ethernet cable running thru my surge arrestor (which does have a slot for Ethernet).

Should I have that hooked up? Will that slow my internet connection?

I am assuming that the phone company has surge suppression on their side of the "NID"?
Old 12-11-14, 07:00 PM
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I wouldn't worry about it too much, as long as your phone or cable line to the modem is surge protected.
Old 12-11-14, 07:05 PM
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I am assuming that the phone company has surge suppression on their side of the "NID"?
That is the assumption we make but it isn't always true. It wouldn't hurt to make sure your NID is actually connected to a ground especially if you are using DSL service.
Old 12-12-14, 07:20 AM
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I would put a surge protector on the phone side of the DSL modem. It shouldn't be more than $10 and won't reduce the connection speed.
Old 12-12-14, 06:56 PM
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> I am assuming that the phone company has surge suppression on their side of the "NID"?

Your telco has installed your surge protector - the NID. However no protector is protection. Appreciate why protectors adjacent to electronics do not claim to protect from the other and destructive type of surge. And why something completely different (unfortunately also called a surge protector) is that protection.

Incoming TV cable has a hardwire connected to earth BEFORE entering a building. A surge that connects to earth BEFORE entering does not hunt for earth destructively via interior appliances.

Many claim 2 cm parts inside a protector will stop what three miles of sky could not. Many claim a hundreds or thousand joule protector will absorb surges that are hundreds of thousands of joules. A facility that must not suffer damage uses the other solution. Protection is always about earthing a surge current BEFORE it enters a building. Then hundreds of thousands of joules harmlessly dissipate outside without damaging anything inside.

That is what the NID protector does. However, if a surge is all but invited inside via AC electric wires, then a surge will go hunting for earth via interior appliances (ie DSL modem). A best path to earth is incoming on AC mains and outgoing to earth via DSL telephone wire. Notice where damage happens. On the phone port. Damage occurs on the outgoing path. Telephone wire is not the incoming path.

Also remember that surges are electricity. A surge on AC mains is incoming to everything. Is everything damaged? Of course not. To have damage means an incoming current path AND an outgoing path to earth ... both must exist. And nothing stops that current.

If any wire enters a building without first connecting to single point earth ground, then protection is compromised. Cable has best protection using only a hardwire connected low impedance (ie 'less than 10 feet') to earth. Telephone makes a same earth connection via the telco 'installed for free' protector in its NID. That protector is only doing what a haredwire would do better.

Same solution must be installed on each incoming AC electric wire. A 'whole house' protector in a breaker box or behind an electric meter is essential. So that a surge need not find earth destructively through a DSL modem via the telco installed protector.

Protector on Ethernet cable has no purpose other than to somehow magically block a surge. That will not happen. And is not necessary IF a surge is earthed BEFORE entering the building.

BTW, ethernet ports already have protection rated about 2000 volts.

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