Results 1 to 15 of 15

Thread: Surge/lightning spike protector for Telstra NBN modem?

  1. #1
    Premium Member
    Join Date
    Dec 2013
    Location
    Cairns
    Posts
    27
    Thanks
    83
    Thanked 3 Times in 3 Posts
    Rep Power
    61
    Reputation
    70

    Default Surge/lightning spike protector for Telstra NBN modem?


    Recently we had a violent thunderstorm here in Cairns. I was home and didn't think to disconnect the phone, power and TV antenna cables from the wall sockets. Bad move.
    There was a lightening strike very close to my place, and simultaneously my modem lit up and made a very loud crack sound, absolutely freaking the dog out, (already disturbed by the thunder).
    Needless to say, the modem was toast. I have had it apart and verified that the spike entered via the RJ12 port and fried a chip (exploded) and several other components. Three neighbours lost their modems as well.

    In the nanoseconds that this happened, the spike was able to pass through the modem and take out the Ethernet circuitry on my PC mother board, before going open circuit.
    I happened to have a spare modem (long story), plugged it in - all good, except that I couldn't connect to the internet.
    The power for my PC and other peripherals such as the modem power pack, cordless phone, monitors, and printer all go through a UPS which is supplied AC through a power board with protection.
    However, I had not fed the phone cable, (I have FTTN not FTTP), through the power board RJ12 I/O sockets because I had read that it hinders the NBN speed.

    This brings me to my question, (sorry it took a while), but can someone give a definitive answer on whether or not a surge protector will hinder the NBN signal, and if not; is there a quality device that is up to the job?

    Thanks guys
    PB



Look Here ->
  • #2
    Senior Member
    Philquad's Avatar
    Join Date
    Jan 2008
    Location
    nelson bay
    Age
    50
    Posts
    3,666
    Thanks
    177
    Thanked 1,150 Times in 689 Posts
    Rep Power
    529
    Reputation
    13838

    Default

    dunno if this helps you any, as i dont run my phone lines through a power board, but i have 1 power board from the power point that has the modem (always on) plugged into it, then another power board that plugs into the 1st one
    that way at night, i can turn off the top board, shutting down all power to computer, printer, speakers, lcd ect (stop all them nasty blue lights)

    then i realized what you said as my modem is still hooked to computer via lan cable, umm, put a $10 usb wireless in your pc, that will fix it
    why do we need the NBN ? because the copper network is constipated & needs fibre

  • The Following User Says Thank You to Philquad For This Useful Post:

    peteblundoon (04-03-18)

  • #3
    Premium Member
    Join Date
    Dec 2013
    Location
    Cairns
    Posts
    27
    Thanks
    83
    Thanked 3 Times in 3 Posts
    Rep Power
    61
    Reputation
    70

    Default

    Thanks Philquad. I am currently using an Ethernet to USB adapter to be able connect to the internet, but I think that your idea is even better.
    I'm actually having a problem with the internet dropping out occasionally in a very random manner - maybe twice a day. Maybe I haven't introduced the adapter to my PC properly.
    I did have to reset the modem for it to connect in the first place.

    It occurred to me that I should test the RG12 surge/spike protector on my power board (a Monster MDP 650G), before and after connecting my modem via the RJ12 I/O sockets on the power board.
    I used the Telstra, CNet and ZdNet speed test websites, (which consistently show vastly different speeds), and found no difference in speeds before and after connecting via the power board.
    I haven't been able to find the specs on this power board, so I don't know what sort of circuitry or components are used - MOV's, Gas Discharge Tubes, Silicon Avalanche Diodes?
    Hope that I don't find out the hard way that, in spite of the Monster being an expensive high-end product, that it's not up the job.

  • #4
    Premium Member
    LeroyPatrol's Avatar
    Join Date
    Jan 2008
    Location
    N.E. Vic
    Posts
    15,579
    Thanks
    3,087
    Thanked 4,234 Times in 2,561 Posts
    Rep Power
    1391
    Reputation
    37031

    Default

    I did some high voltage testing when at Telstra years ago and the devices that were on the lines were seen as high resistive to earth so didn't affect performance. Only when a voltage on the line exceeded a certain level would the devices conduct these surges to earth. But generally we found any of the cheap surge protection devices sold didn't really protect against big surges ie direct lightning strikes.

    Leroy

  • The Following 2 Users Say Thank You to LeroyPatrol For This Useful Post:

    peteblundoon (07-03-18),shred (10-03-18)

  • #5
    LSemmens
    lsemmens's Avatar
    Join Date
    Dec 2011
    Location
    Rural South OZ
    Posts
    7,188
    Thanks
    6,090
    Thanked 3,928 Times in 1,975 Posts
    Rep Power
    1718
    Reputation
    69820

    Default

    The thing is, if ANY device that is not protected is connected to a protected device, you may as well have NO protection at all. Lightning, like any other electricity will always follow the path of least resistance to earth.
    I'm out of my mind, but feel free to leave a message...

  • The Following User Says Thank You to lsemmens For This Useful Post:

    peteblundoon (07-03-18)

  • #6
    Junior Member
    Join Date
    Sep 2011
    Posts
    11
    Thanks
    0
    Thanked 3 Times in 3 Posts
    Rep Power
    0
    Reputation
    70

    Default

    Quote Originally Posted by peteblundoon View Post
    Hope that I don't find out the hard way that, in spite of the Monster being an expensive high-end product, that it's not up the job.
    Monster has a long history of identifying ineffective and popular devices. Then selling a same product, with an expensive looking box, for much higher prices. Money says nothing about protection. Specification numbers do.

    Since adjacent to an appliance, then it must 'block' or 'absorb' a surge. How many joules does it claim to 'absorb'? Potentially destructive surges are hundreds of thousands of joules. Note a problem?

    No protector does protection. An effective protector connects low impedance (ie less than 3 meters) to something completely different that does that protection. A protector is only as effective as its earth ground.

    Effective protection means a surge is nowhere inside. Then everything is protected. That means every incoming wire must connect low impedance (ie less than 3 meter) directly or via a protector to that same earth electrodes.

    A surge incoming on an AC wire is inside hunting destructively for earth. A most common path is incoming to a modem. Then outgoing via its internet cable. If both an incoming and outgoing path does not exist, then no surge existed. A surge incoming to all appliances only damages what also has an outgoing path. Damage is often on the outgoing side - that internet wire.

    Too many use observation to make a conclusion. Since damage was on an internet connection, then a surge must have been incoming on that wire. The most common incoming path (because so many do not properly earth a 'whole house' solution) is AC mains. Damage on its outgoing path.

    Internet providers often recommend no protectors on their cable. Capacitance of so many such protectors (with obscene profit margins) is excessive (as well as not have a low impedance connection to earth). Then Signal to Noise ratios are too low - causing intermittent operation.

  • The Following User Says Thank You to westom For This Useful Post:

    peteblundoon (07-03-18)

  • #7
    LSemmens
    lsemmens's Avatar
    Join Date
    Dec 2011
    Location
    Rural South OZ
    Posts
    7,188
    Thanks
    6,090
    Thanked 3,928 Times in 1,975 Posts
    Rep Power
    1718
    Reputation
    69820

    Default

    A surge can, and does come in via the copper of the POTS network. I've seen the effects, and had to repair some of it. I was asked to go and provide a temporary service to a business that had suffered a strike. The first tech that went out there came home in an ambulance, lightning hit the line again as he was re-terminating the cable. There was a black strip up the wall where the lead in cable had been. The receptionist, behind a desk on the opposite side of the room had a bandage on her head where the cover from the distribution box had blown across the room and hit her. I was, of course doubly cautious.
    I'm out of my mind, but feel free to leave a message...

  • The Following User Says Thank You to lsemmens For This Useful Post:

    peteblundoon (07-03-18)

  • #8
    Junior Member
    Join Date
    Sep 2011
    Posts
    11
    Thanks
    0
    Thanked 3 Times in 3 Posts
    Rep Power
    0
    Reputation
    70

    Default

    Quote Originally Posted by lsemmens View Post
    A surge can, and does come in via the copper of the POTS network.
    Why was it incoming? Because it did not have protectors that were properly earthed. Accurately noted, "Lightning, like any other electricity will always follow the path of least resistance to earth." However one word is wrong. It follows the path of least impedance to earth.

    Phone lines typically have protectors. But if that protector is not properly earthed (ie connected less than 3 meters to the single point ground), then that line has no protection. Protector and protection are different items.

    Lightning (and other surges) must have both an incoming path and an outgoing path to earth. If only one wire is properly earthed by a protector, then that outgoing wire (not the incoming wire) line is often a damaged side.

    How to avert damage? Spend less time viewing protectors. Spend more time learning and upgrading the item that actually does and defines protection.

    Some protection 'systems' do not have protectors. But every effective 'system' always has a single point earth ground. Because a protector is only as effective as its earth ground.

    Protection increases when that distance to earth is shorter. Protection increases when separation between appliance and protector increases. Because of a critical factor to all protection. Impedance. Greater separation increases impedance and therefore increases protection. Shorter connection to earth decreases impedance and therefore increases protection.

    Otherwise an outgoing path is often damaged. Since THE most common incoming path is AC electrics. Incoming to everything.

  • #9
    LSemmens
    lsemmens's Avatar
    Join Date
    Dec 2011
    Location
    Rural South OZ
    Posts
    7,188
    Thanks
    6,090
    Thanked 3,928 Times in 1,975 Posts
    Rep Power
    1718
    Reputation
    69820

    Default

    Fair enough. Impedence is really only applicable to AC circuits,
    Impedance extends the concept of to AC circuits, and possesses both magnitude and , unlike resistance, which has only magnitude. When a circuit is driven with (DC), there is no distinction between impedance and resistance; the latter can be thought of as impedance with zero
    We agree that protection is only as good as its weakest link.
    I'm out of my mind, but feel free to leave a message...

  • #10
    Junior Member
    Join Date
    Sep 2011
    Posts
    11
    Thanks
    0
    Thanked 3 Times in 3 Posts
    Rep Power
    0
    Reputation
    70

    Default

    Quote Originally Posted by lsemmens View Post
    Fair enough. Impedence is really only applicable to AC circuits, from WIKI[/URL] We agree that protection is only as good as its weakest link.
    That statement is too vague to make any conclusion here.

    Put numbers to it. For example, a plug-in protector and computer has a tiny 100 amp incoming surge. That receptacle is maybe 50 feet from the breaker box. That would be less than 0.2 ohms resistance. And something like 120 ohms impedance. 100 amps times 120 ohms puts that computer and protector at something less than 12,000 volts. Impedance is critical. Resistance says nothing useful.

    Why less than 12,000 volts? Because that surge will find other paths to earth destructively through an attached computer or via any other nearby appliance. An IEEE brochure even puts a numbers to it. A plug-in protector earthed a surge 8000 volt destructively through a TV in the next room because a plug-in protector was used and because a 'whole house' protector was not properly earthed.

    No protector does protection. Effective protectors answer this question. Where do hundreds of thousands of joules harmlessly dissipate? A protector is only as effective as its earth ground. Concepts such as impedance, equipotential, conductivity, and single point earth ground apply.

  • #11
    Junior Member
    Join Date
    Jan 2008
    Posts
    211
    Thanks
    30
    Thanked 19 Times in 18 Posts
    Rep Power
    143
    Reputation
    200

    Default

    What are your thoughts on GPO surge protectors?

    I was told they need to be the first GPO in a circuit, but how effective will they be?
    Shows only up to 140joules

  • #12
    Junior Member
    Join Date
    Sep 2011
    Posts
    11
    Thanks
    0
    Thanked 3 Times in 3 Posts
    Rep Power
    0
    Reputation
    70

    Default

    Clearly stated were requirements for an effective solution. Long before posting, these answers were already (should have been) known.
    Effective protectors answer this question. Where do hundreds of thousands of joules harmlessly dissipate?
    Where was that answered?

    A protector is only as effective as its earth ground.
    What defines / provides that a low impedance connection to earth?

    Concepts such as impedance, equipotential, conductivity, and single point earth ground apply.
    Where was that discussed or considered?

    Where are the always required specification numbers? No numbers is the first indication of a recommendation without honestly or knowledge.

  • #13
    Junior Member
    Join Date
    May 2018
    Posts
    10
    Thanks
    4
    Thanked 1 Time in 1 Post
    Rep Power
    0
    Reputation
    30

    Default

    If it's FTTN my advice would be to contact NBN.

    I don't know if it's the same in other states but here in SA they have surge protectors that can go in a (Network Termination Device) NTD enclosure although they aren't free and just "Wanting" one generally isn't a good enough reason.

    In terms of speeds... You may notice some difference if you use a powerboard because the 240 volt will more than likely create some interference, how much depending on the load and if you have any adaptors/transformers running.

    You can get passive surge protection components however these are more designed for commercial use and can be difficult to fit due to... as said above... how the surge protector is installed.

    Have a look in around the NBN site... I remember seeing a PDF somewhere in there about them.

  • #14
    Premium Member

    Join Date
    Jan 2008
    Location
    Central Tablelands of NSW
    Age
    75
    Posts
    13,753
    Thanks
    1,232
    Thanked 3,760 Times in 2,496 Posts
    Rep Power
    1711
    Reputation
    56066

    Default

    Power boards seem to have some weird effects on computer equipment as I remember a Bro-in-Law couldnt get a printer to work unless it was plugged directly into a wall outlet.
    I have noticed on one power board that you MUST make sure the plug is inserted fully as even a few mm's out and whats plugged in wont work.
    I have put this down to the later version of plugs with that 'sleeve' on the pins and the internals of the board have only a small exposed of area to make contact with.
    Over the years I have witnessed some scary electrical storms here and have seen the Mains Transformer for the Village hit (outside my front door) and damaged but I never lost a thing and then the one that took out the the TV and cordless phone etc wasnt that close to me.
    I stand unequivicably behind everything I say , I just dont ever remember saying it !!

  • #15
    Premium Member

    Join Date
    Jan 2008
    Posts
    3,956
    Thanks
    4,989
    Thanked 3,819 Times in 1,596 Posts
    Rep Power
    1105
    Reputation
    42118

    Default

    Quote Originally Posted by gordon_s1942 View Post
    Power boards seem to have some weird effects on computer equipment as I remember a Bro-in-Law couldnt get a printer to work unless it was plugged directly into a wall outlet.
    This is a common phenomenon when using a network printer connected to a server/computer via a 'Powerline networking system' (see ).

    I have noticed on one power board that you MUST make sure the plug is inserted fully as even a few mm's out and whats plugged in wont work.
    I have put this down to the later version of plugs with that 'sleeve' on the pins and the internals of the board have only a small exposed of area to make contact with.
    This is a safety requirement (see below), which roughly translated states that a "standard finger" must be incapable of coming into contact with any exposed metal of the power plug pin when placed between the mains plug and the receptacle (in this case, the mains socket on the power board). The same restriction applies to power points.[/QUOTE]



    The plug pictured on the left, as used in Australia, New Zealand, Fiji, Papua New Guinea and many Pacific Island countries, has two flat pins forming an inverted V-shape plus a vertical earthing pin. These flat blades measure 6.35 by 1.6 mm (1⁄4 by 1⁄16 in) with the Active and Neutral pins 17.35 mm (11⁄16 in) long set 30 to the vertical and the vertical Earth pin being 20 mm (0.787 in) in length.[2] The pins are arranged at 120 angles around a common midpoint, with the Active and Neutral centred 7.92 mm (5⁄16 in) from the midpoint, and the Earth pin centred 10.31 mm (3⁄8 in) away.[2]

    As from 3 April 2005 the "live" (Line and Neutral) pins of every 10 amp and 15 amp flat pin plug sold were required to comply with the requirements of AS/NZS 3112: 2000, which states that the live pins must be insulated, as shown in the picture. ().

  • Bookmarks

    Posting Permissions

    • You may not post new threads
    • You may not post replies
    • You may not post attachments
    • You may not edit your posts
    •