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| Thread ID: 26411 | 2002-10-26 21:10:00 | Underground Phone Cables | Danger (287) | Press F1 |
| Post ID | Timestamp | Content | User | ||
| 93320 | 2002-10-27 03:11:00 | well it's a nasty little storm here... rocks of ice are falling on the roof and i'm glad the office sound is 200W and concert JBL It's up so loud that the meters are moving and i can still here the hail! flash bang... flash bang... I aint going outside in this! Just glad i've got services up to an innercity standard, if i were out at my better½s in weather like this it would be quick unplug the computer time! |
Clueless (181) | ||
| 93321 | 2002-10-27 03:20:00 | true..if it gets a direct hit which is extreamly rare(it totalled most of the house). lighting will go down the path of least resistance. a big strike will usually fry the conductors which tends to help stop the rest of it go through. a decent protector can save it but a big strike will simply jump over the cables and find the closest earth. however it isn't always lightening that spikes equipment. seen an alarm panel destroyed by a spike down the phone lines one a clear night, no lightning, no power failures, car crashes etc, with a direct line to the exchange. go figure. |
tweak'e (174) | ||
| 93322 | 2002-10-27 03:53:00 | well I sure as hell am glad that I've got a surge protector, comp and phone. Before the computer rebooted and the TV reception disappeared :O |
-=JM=- (16) | ||
| 93323 | 2002-10-27 03:59:00 | Got that here too JM, must have been a SI system disturbance. That WASNT a surge though, it was a brown-out, the opposite of a surge. Thats a case where a cheap UPS would have worked, to fill in the missing bit. |
godfather (25) | ||
| 93324 | 2002-10-27 04:41:00 | Telstra Coaxial network. The fibre optic cable is used as a link between the OTN, Mux's and the switch. OTN = converts fibre to coax Mux = converts fibre to telephony switch = data exchange Fibre optic is only used for main express transmission line or city link fibre net connections. Coaxial network should be earthed at Amps and end of line terminations. Telephony is only earthed at the mux cabinets. All coxial network for one node is joined together to the stand wire and which should be earthed, so if one part gets hit with a charge it will make live the rest of the network if not earthed properly. This includes underground network too. Coxial network carries a max charge of 63 volts AC and approx 24 Volts DC. |
333littledevil (2353) | ||
| 93325 | 2002-10-27 04:43:00 | Also most fibre optic is just straight plastic with kevlar braids to strengthen it. It will melt first than carry a charge |
333littledevil (2353) | ||
| 93326 | 2002-10-27 04:48:00 | Hi people,just a point.Strikes that effect the phone lines,and end up blowing phone jacks off the wall and frying PC's,doesn't have to happen anywhere near you to do the damage.We have heaps of occurances of lightning striking miles away from the damage.Phone cables are great conductors so the voltages will go a long way,and can come out anywhere,so in country areas surge protectors are a good idea. Also, you won't get a surge from the exchange going down,and coming back up again,as the exchange doesn't go down.It automatically switches to battery backup if the power goes off,and even if you were on the phone at the time it changed over,you wouldn't even know. Peter |
Peter Coleman (597) | ||
| 93327 | 2002-10-27 07:31:00 | 333littledevil, a question for you! > All coxial network for one node is joined together to > the stand wire and which should be earthed, so if one > part gets hit with a charge it will make live the > rest of the network if not earthed properly. This > includes underground network too. So how large an area is covered in one node in terms of households or streets? I'm assuming that the OTN's and the Mux boxes are those HUGE green boxes on the accational corner? If everything around me is underground, does that mean that the chances of lightning getting in is next to nothing? BTW is there anything to keep the system going in event of local power failure? |
Clueless (181) | ||
| 93328 | 2002-10-27 09:14:00 | > Got that here too JM, must have been a SI system > disturbance. > > That WASNT a surge though, it was a brown-out, the > opposite of a surge. > Thats a case where a cheap UPS would have worked, to > fill in the missing bit. Thanks for that godfather. I just assumed that it was a lightning strike as their was electricity in the air at the time. So thought it was a surge. Funny thing is that the fax didn't give an error print out. So maybe that wasn't affected. |
-=JM=- (16) | ||
| 93329 | 2002-10-27 09:24:00 | most machines have some sort of capacistor in the power supply that is there to smooth the ripples out of the power that the said machine runs on. Remember that mains is AC (alternating) current it drops and cahnges direction and back 50 times a second. what electronic toys generally like is DC, which is dead contant The capacitors work like little batterys, and smooth the recified AC into a a near contant voltage. If these caps are small, they will not prevent a fraction of a seconds worth of brown out. If they are large and also if the appliance is not running at full load (like your idle fax) then they will keep things going through a momentary drop in the supplie To see what they can do.. pull the plug on a decest sized audio amplifier sometime, it will keep going for a few seconds, and then the quality will turn to muck as the last of the power is drained from the caps. |
Clueless (181) | ||
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