You never know which direction the surge is coming from, many times, perhaps
most times, it comes from the power lines and originates in the NOC gear.
And with a piece of CAT 5 going in and out of a surge protector, you never
know what the surge protector is connected to. A surge protector is
essentially a piece of CAT 5 or a CAT 5 coupler with a few extra components.
There really is no direction to them or a "tower side" to them.
I could fuse all 8 wires. And have double surge suppressors. Or just put
surge on one side and label it "tower".
How do you detect the direction of a nanosecond rise time pulse? You would
have to have an RF reflectometer on each of the 8 wires tied to some fast
logic. You would want sub microsecond switches that open the CAT5 and
logic to figure out where the pulse comes from and send it where? If it is
a powered wire on the POE where do you want that connected to during the
pulse?
All surge suppressors I have ever seen do things essentially the same way I
do things.
In any event, I will post this to the group. Perhaps there is a learning
opportunity for me here. Like to see if others have seen their POE blow
when shorted. I personally have not seen this before.
-----Original Message-----
From: Matt Hoppes
Sent: Monday, March 20, 2017 5:46 PM
To: Chuck McCown
Subject: Re: Question on APC Arresters
I'm not sure what the better option is. Not clamp on the power side, isolate
and clamp on the tower side only?
So a surge comes in, break the connection between ground and tower and only
shunt tower side to ground.
Honestly we were extremely surprised to find these did anything on the near
side of the unit. That came as a shock.
Netonix. Toughswitch. Tycon. Anything that isn't AF and is passive PoE
blows.
On Mar 20, 2017, at 19:29, Chuck McCown <[email protected]> wrote:
So, what would you have a suppressor do? Not clamp to ground?
I have not run into POE switches that will blow if shorted. They are
energy limited.
What kind of switch?
-----Original Message----- From: Matt Hoppes
Sent: Monday, March 20, 2017 4:28 PM
To: Chuck McCown
Subject: Re: Question on APC Arresters
So the problem we are running into is the suppressor fires and clamps
which shorts the power supply on the switch, which kills the switch
port. Now I'm out both a switch port and a suppressor.... I'm not sure
what I've gained.
River Valley Internet
"We Never Forget You Have a Choice"
570-433-7070 x 700
On 3/20/17 6:13 PM, Chuck McCown wrote:
Yes, they are clamping the wire. So think of most of our devices as 8
individual surge suppressors. They will short the impulses to ground.
If (as is common) the impulses come in on all 8 wires at the same time,
all 8 wires are connected to ground and as a result they are also
connected to each other.
-----Original Message----- From: Matt Hoppes
Sent: Monday, March 20, 2017 4:06 PM
To: [email protected]
Subject: Question on APC Arresters
Hey Chuck... was discussing your Ethernet arresters last night.
Is it normal operating mode for them, when they take a strike, to go
into a "short circuit" situation on both sides of the Ethernet port?
