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Walter Dnes
join:2008-01-27
Thornhill, ON

Walter Dnes

Member

Should I bypass UPS surge-protection for ADSL modem?

My condo building's FTTN seems to be an IKNS (Stinger?) according to my ADSL modem diagnostics. I'm on Teksavvy 7/1 megabit service. My nominal connection is 8.51 megabits down and 824 kbits up. Speedtest.net shows net throughput approx 7.03-to-7.15 down and 670 kbits up. The upwards SNR is rather marginal, at 6.5 dB.

This may be due, in part, to my paranoid surge-protection. My current setup is...
* phone line from wall outlet to UPS phone out
* splitter connected to UPS phone in
** 1 of the 2 splitter-to-UPS outlets is used by the ADSL modem
** the other splitter-to-UPS outlet is used by an ADSL filter with 2 outlets
*** 1 of the filtered outlets is used by an extension phone
*** the other filtered outlet is used by a USB dialup modem for emergency backup

With this setup...
===========
Note; ST546 is European. Commas and decimal points are swapped.
Bandwidth (Up/Down) [kbps/kbps]: 824 / 8.510
Output Power (Up/Down) [dBm]: 12,0 / 21,5
Line Attenuation (Up/Down) [dB]: 2,5 / 4,0
SN Margin (Up/Down) [dB]: 6,5 / 24,5

Speedtest.net result (Teksavvy) ping 23 ms; down 7.09 Mbps; up 0.67 Mbps

Bypassing the fancy scheme, and connecting the modem directly to the wall outlet, with no splitters, is similar. I'll just list the changes...
===========
Line Attenuation (Up/Down) [dB]: 1,5 / 3,0
Speedtest.net result (Teksavvy) ping 15 ms; down 7.02 Mbps; up 0.67 Mbps

My question is... how large is the risk in connecting the modem directly to the wall outlet? Has anybody had their modem (or worse, their PC) damaged by power surges? The direct connect doesn't seem to give me any major improvement, so it's probably not worth it. Or am I missing anything?
westom
join:2009-03-15

1 edit

westom

Member

said by Walter Dnes:

My question is... how large is the risk in connecting the modem directly to the wall outlet? Has anybody had their modem (or worse, their PC) damaged by power surges?

Destructive surges are rare - maybe once every seven years. Effective protection inside electronics makes most transients irrelevant.

Best protection means a protector connected as close as possible (ie less than 3 meters) of a single point earth ground. And as much separation as possible between a protector and electronics. Concepts are discussed in »AT&T Southeast Forum FAQ »How can I protect my DSL/dialup equipment from surges?

Relevant points are found after the subtitle "Surge Protection:" starting with:
quote:
Surge protection takes on many forms, but always involves the following components: Grounding bonding and surge protectors. ...
Grounding is required to provide the surge protector with a path to dump the excess energy to earth. A proper ground system is a mandatory requirement of surge protection. Without a proper ground, a surge protector has no way to disburse the excess energy and will fail to protect downstream equipment.
Your DSL service should already have a best protector installed for free. Your concern is an AC mains protector that (as the FAQ notes) is only effective when earthed to the same ground used by that telco 'installed for free' protector.

Read numeric specs for that UPS protector. Does not even claim to protect from a typically destructive surge. Repeatedly violates principles defined in the AT&T FAQ. Its near zero protection is just enough above zero so that advertising can hype it as 100% protection.

Protection was never about a protector. Protection was always about what does protection - the earth ground. UPS protector does not discuss earthing because it has none.

MacGyver

join:2001-10-14
Vancouver, BC

MacGyver to Walter Dnes

to Walter Dnes
Bypass the phone line and networking "protection" in surge strips and UPS's. They are just hype.

JC_
Premium Member
join:2010-10-19
Nepean, ON

JC_ to Walter Dnes

Premium Member

to Walter Dnes
You might as well just bypass the phone surge but just use AC surge, even if there is a surge on the phone line a new modem for ADSL/ADSL2+ only cost around $20-30.

On all phone lines there is protection built into the distribution at every connection point, since you're in an apartment the grounding and surge protection is in the IT room.
Walter Dnes
join:2008-01-27
Thornhill, ON

Walter Dnes

Member

Thanks for everybody's input. I've re-arranged things so that the ADSL network connection connects directly to the phone jack in the wall. The AC power plug is still surge protected. Here is the comparison...

ADSL network via UPS surge protector
========================
Bandwidth (Up/Down) [kbps/kbps]: 824 / 8.510
Data Transferred (Sent/Received) [KB/KB]: 0,00 / 0,00
Output Power (Up/Down) [dBm]: 12,0 / 21,5
Line Attenuation (Up/Down) [dB]: 2,5 / 4,0
SN Margin (Up/Down) [dB]: 7,0 / 24,5

ADSL network directly connected to phone jack in wall
==================================
Bandwidth (Up/Down) [kbps/kbps]: 856 / 8.510
Data Transferred (Sent/Received) [KB/KB]: 0,00 / 0,00
Output Power (Up/Down) [dBm]: 12,0 / 21,5
Line Attenuation (Up/Down) [dB]: 1,5 / 2,5
SN Margin (Up/Down) [dB]: 6,0 / 24,5

Net difference
=========
upload speed goes up from 824 to 856 kbits
line attenuation reduced 1 db upload, and 1.5 db download
Upload SN Margin reduced 1 db. Probably due to higher upload sync.
On Speedtest.net, my upload test increases from 670 kbps to 700 kbps. This is the first time I have ever hit 700 kbps upload.

It's a minor improvement overall, but I'll take it.

Guspaz
Guspaz
MVM
join:2001-11-05
Montreal, QC

Guspaz to Walter Dnes

MVM

to Walter Dnes
If you're using ethernet anywhere there, you're effectively unprotected. The surge will come in via the phone line, hit the modem/router, and go out via the ethernet cable to fry all your other surge protected hardware.

Modems are cheap and don't contain important data (it sucks if you have to pay $150 for a new one, but you won't lose any data you care about), so it makes sense to put them on the unprotected side of the equation.

So, my suggestion:

Phone line -> Modem -> Ethernet cable -> UPS -> Ethernet cable -> Router -> Network

No point surge protecting the AC on the modem at that point, I'd think.