The nbn electrician suggests that hfc is vulnerable to electrical surge and thunderstorms.
Does anyone know if it's a good idea to channel the fibre through a surge protector such this one https://www.amazon.com.au/dp/B0748MQXP5/ref=cm_sw_r_other_ap…
Keen to know if I would lose substantial speed or not, and if not any small/cheap surge protector you can recommend as I only need 1 port.
He said all hfc, this is the disadvantage of it.
I don't care about the nbn modem, but I care about all my others.
The are trying to up sell and get you to buy something.
Ignore, don’t buy it. You don’t need it at all.
It was telstra technician, but what could he possibly want me to buy from him?
I asked him if it's worthwhile applying to switch to fttp, and he said no need, hfc is good, the only downside is as I said before
@[Deactivated]: HFC is fine. He was upsellin* a filter. You don’t need one and it isn’t true that it wouldn’t be fixed if damaged by a storm/gone faulty.
You originally said an NBN tech, NBN and Telstra is different.
@PVA: I signed up nbn with iinet, iinet said its nbn technician, the person who comes has telstra badge however.
So there is no point to change hfc to fttp then? Why is there an option to do that then?
@[Deactivated]: In case anyone sees this post because it comes up on Google, the tech was right. You can have surges that destroy your ntd and other devices up stream from it.
Ubiquiti make a cat6 surged protector that works.
I had the coax protected by a power board but the NTD still died. So I'm now looking for something else. Yes it doesn't cost you to get NBN to replace it but you are down for a day or two waiting for them to come out.
HFC is a copper core shielded cable. Any lightning strike will hit the outside which is earthed.
How about electrical surge?
There should be a 3.5kV inline isolator installed on the outside of your house.
Doesn't make sense. Then what is the disadvantages of hfc?
@[Deactivated]: If that really an issue, then it would be mandatory for surge protectors to be used. It obviously is not an issue. Secondly, the most you will fry is the aerres box and the modem, which will be replaced :). PLus it is underground, what are the chances lightning will hit your the earth above your cable and then go to your cable? which is shielded. Like come on, think about it.
It has been used for Foxtel for years, have they had any serious issues? no because it is reliable and hence why it is now used for nbn
@hmac: What is the disadvantages of hfc? This is the electrician answer.
Thanks for your guess. Good guess, but guess it seems still though. Isn't it?
@[Deactivated]: Not sure your q but you have a surge protector in the isolator box outside. You don’t need an internal one.
Likely the company the is the contractor for NBN has asked their installers to up sell (I know Telstra did it a few years back) or the installer just has no clue about the HFC network (a lot of contractors come from many areas, mechanics, taxi drivers, anywhere, they are not engineers and honestly don’t get a massive amount of training.
@PVA: That part makes sense, what doesn't to me is why do people think hfc is worse than other kind.
@[Deactivated]: there was controversy when it came out, but it is capable of providing faster reliable speeds than FTTN/C/B
@hmac: HFC needs constant upgrading and maintenance thanks to the way it transfers data. Every upgrade to consumers from here on out, on hfc, will require millions and millions of investment. Not to mention constant callouts due to its unreliability and nbns insistence that rsp's supply dynamic public ip over dhcp which has its own weaknesses. The taps are also vulnerable to flooding because they are not designed to be undergound. Theres also massive upload contention on hfc which is the biggest hurdle and will require more billions in investment to get it to what fttp offers now for upload in NZ(also here for business plans)
hfc is also very esoteric so it's harder to find experienced engineers/technologists who have not moved onto bigger and better things. It took years for telstra and optus to provide a reliable broadband service on hfc.
It offers great download speeds, up to 750Mbps for some in australia, when its working however its an archaic technology. fttc, aka frankenstein's baby, was engineered because of how expensive it would be to service more homes with nbn hfc. fttc also offers a cheaper upgrade path than hfc because all you have to do is replace the units underground.
@hmac: What part isn't fact? many experts have stated that the hfc remediation has been costly, a waste of money and it still remains 10 times as unreliable as the fttp network. Future generations are going to have foot the bill again to finally replace this archaic technology. Many billions sunk into hfc remediation and the service unreliability complaints keep showing.
Overseas hfc networks have demonstrated you need constant investment to refurbish and maintain a coaxial to the node network.
Dropouts are unacceptable no matter what nbn or your isp tells you.
On the weekend we had a severe electrical storm. All my network devices mentioned below (and other devices) were plugged in to a decent (I think) surge protector (https://www.cyberpower.com/au/en/product/sku/br700elcd).
In the house, what I believe was a surge took out my NBN NTD connected to HFC. Connected to the NTD was a Unifi USG, which survived. However, it also took out a switch which was connected to the USG. In the shed down the back, another switch powered by a BR700ELCD UPS and connected to the USG connected switch was also taken out. Other devices on this UPS in the shed survived.
I'm now uncertain what was the cause. If it was a spike from the HFC, why wouldn't the USG which was the only device connected to the NBN NTD be damaged, yet the switch connected to it was, as was the next switch connected to the first switch? Why weren't all the devices connected to the damaged switches also damaged? If the UPS is toblame, why weren't the other devices connected to the same UPS weren't damaged. Could it be that the USG was just lucky, and the surge passed through it from the NTD to take out the other 2 switches, or should be be blaming the UPS?
If the cause was indeed a surge from the HFC, protection would be a good idea. The tech who replaced the NTD yesterday said many were being replaced, and he didn't know of any protection devices available.
Any ideas on the cause and solution?
A solution (and reasons for damage) was well understood even over 100 years ago. A concept originally demonstrated by Franklin over 250 years ago.
A destructive current seeks earth ground. One conductive path to earth was a wooden church steeple. Wood is not conductive enough. Massive amperage creates a high voltage. Destructive energy dissipates inside on a path to earth ground..
Did Franklin stop or absorb surges? Of course not. Franklin simply diverted lightning to earth. A conductive path that remained outside meant 10,000+ amps caused no damage (no destructive voltage). Entire surge harmlessly dissipated outside in earth.
A destructive current seeks earth ground. One conductive path to earth is any household appliance. Appliances are not conductive enough. Massive amperage creates a high voltage in each appliance. Destructive energy dissipates inside on a path to earth ground..
What inside will stop or absorb surges? Nothing. An effective protector simply diverts lightning to earth. A conductive path that remained outside (and low impedance) means 10,000+ amps caused no damage (no destructive voltage). Entire surge harmlessly dissipated outside in earth.
Clearly that did not exist. NBN cable, if properly installed, already is connected low impedance (ie less than 3 meters) to earthing electrodes.
Surge damage only exists when that current has an incoming and another outgoing path. Incoming to everything on AC mains. Now hunting for earth ground. A best outgoing path is that NBN cable (that should be properly earthed). A best outgoing path via a modem.
Damage is often on the outgoing path. Then wild speculation assumes that was an incoming path.
That surge was incoming to everything. Since a best outgoing path was via a modem, then that modem protected a dishwasher, LED & CFL bulbs, furnace, digital clocks, refrigerator, RCDs, door bell, central air, microwave, recharging electronics, clock radios, dimmer switches, and smoke detectors.
Protection only exists when every wire inside every incoming cable makes a low impedance (ie less than 3 meter) connection to the same earth ground electrodes. Before entering. Only then do hundreds of thousands of joules dissipate harmlessly outside. As Franklin demonstrated over 250 years ago. As found in every Telstra switching station - that suffers about 100 surges with each storm. And no damage.
Best protection cost about $1 per protected appliance. And is completely unknown to most. Since most only know what advertising has ordered them to believe. Rather than learn from 100 years of well proven science.
That 'whole house' solution is essential to even avert what firemen learned the hard way. No plug-in protector claims effective protection. Anyone who learns what a protector does and learns its near zero joule numbers (always read specification numbers) would understand why so many protectors nearly created a firehouse fire: http://www.esdjournal.com/techpapr/Pharr/INVESTIGATING%20SUR…
No protector does protection. Not one. A protector is only as effective as its low impedance (ie less than 3 meter) connection to and the quality of single point earth ground. Only then do hundreds of thousands of joules harmlessly dissipate outside in earth - via those electrodes.
Wall receptacle safety ground clearly is not earth ground. A protector is only as effective as its earth ground.
The NBN technician didn't recommend something? If it was such a high risk/high probability event, I would have thought it would be installed with something to mitigate it in the first place.
How often will you not be home during a thunderstorm to unplug the cables?
Also, doesn't the HFC (NTD) modem technically belong to NBN, so if it gets damaged from a storm, wouldn't they replace it free of charge? I mean, you didn't pay for it in the first place right?
In my entire lifetime I've only recently lost an old plasma TV and an ADSL modem to thunderstorm/lightning in the same storm, just a year or two ago.