Kitz Forum

Broadband Related => FTTC and FTTP Issues => Topic started by: cwaite on August 08, 2018, 05:43:42 PM

Title: Thunderstorms Causing FTTC (G.993.2; VDSL2) Problems
Post by: cwaite on August 08, 2018, 05:43:42 PM
We dont get Thunerstorms much here, probably get around 5 a year and even then probably only 3 or 4 rumbles of thunder each time.
 
The past 3 times that we have had thunderstorms in the area, my Fibre connection has disconnected briefly, often resulting in a slower sync rate which usually recovers within a few hours or days, now I know that lightning is capable of causing interference to a number of things, but is this quite normal to do this everytime we have lightning?, the only reason I ask its that I have never noticed lightning causing problems in the past with my VDSL connection

I have recalled the last two dates that we had lightning and attached the stats. Last night the broadband seemed to cut out after the storm had passed which I think is strange.
Title: Re: Thunderstorms Causing FTTC (G.993.2; VDSL2) Problems
Post by: burakkucat on August 08, 2018, 07:59:37 PM
I've made a slight alteration to the subject line to avoid any confusion with usage of the "Fibre" word.

Any xDSL technology can be affected by atmospheric electrical discharges (thunderstorms). The degree of disturbance will be directly proportional to the distance between the discharge and the xDSL circuit. Obviously the closer the storm, the greater the potential for disturbance. If there should be a ground strike adjacent to either the PCP or its "fibre" twin cabinet then I suspect that all circuits will be affected . . . the DSLAM may not survive.

I'm not sure if anything can be deduced from the information you have provided. Nothing is obvious, to me.
Title: Re: Thunderstorms Causing FTTC (G.993.2; VDSL2) Problems
Post by: Ixel on August 08, 2018, 09:08:29 PM
I've never experienced a loss of sync, even during that other thunderstorm earlier this year which almost constantly lit the sky up. I usually experience many errored seconds however, which DLM appears to ignore during a thunderstorm (assuming the threshold for MTBE red is exceeded).
Title: Re: Thunderstorms Causing FTTC (G.993.2; VDSL2) Problems
Post by: cwaite on August 08, 2018, 09:10:17 PM
Thanks for taking a look, was just curious as the storms we have had have been distant and as I said last night it went down about 5 minutes after the last noticable flash of lightning.
Title: Re: Thunderstorms Causing FTTC (G.993.2; VDSL2) Problems
Post by: johnson on August 08, 2018, 09:41:37 PM
Its amazing how sensitive VDSL is to electrical storms. There were maybe 2 audible rolls of thunder yesterday evening where I am and the connection went down twice, both some time after them.
Title: Re: Thunderstorms Causing FTTC (G.993.2; VDSL2) Problems
Post by: Weaver on August 09, 2018, 02:48:53 AM
The charged cloud and charged ground patch may move to a distant area and then be affecting important kit there, such as at the far end of you line, if you have along line, that is. There could be current flow down you line too, duebto the potential difference between the the places where the two ends of the line are, if long line, and this Ground Potential Rise or Earth Potential Rise GPR/EPR could be insidiously harmful, slow cooking. I have heard of kit been heated by this in the USA. I don't know about it here, most lines too short and it often would not be recognised anyway. The ubiquitous popularity of wireless lans has protecteca generation of computers so we do not hear much about lightning damage any more, compared to what it would be like otherwise, with burned out ethernet NICs or worse.
Title: Re: Thunderstorms Causing FTTC (G.993.2; VDSL2) Problems
Post by: cwaite on August 13, 2018, 11:55:49 AM
Had another thunderstorm Friday night and again went off 4 times Friday evening and then once at around 6am Saturday morning, this has cause my interleaving to go from 4 to 8 and my inp to drop from 51 to 44 which I think is a bit strange for the DLM to lower the INP?.
Title: Re: Thunderstorms Causing FTTC (G.993.2; VDSL2) Problems
Post by: j0hn on August 13, 2018, 01:11:59 PM
The changes in INP were a result of DLM changing your line from Retransmission High to Retransmission Low.
Title: Re: Thunderstorms Causing FTTC (G.993.2; VDSL2) Problems
Post by: Weaver on August 13, 2018, 01:32:05 PM
where abouts thunderstorms?
Title: Re: Thunderstorms Causing FTTC (G.993.2; VDSL2) Problems
Post by: cwaite on August 13, 2018, 02:49:37 PM
The changes in INP were a result of DLM changing your line from Retransmission High to Retransmission Low.

Just seems strange I would have thought that if the connection was showing alot of errors then the Re-transmission should have stayed at High?
Title: Re: Thunderstorms Causing FTTC (G.993.2; VDSL2) Problems
Post by: cwaite on August 13, 2018, 02:50:11 PM
where abouts thunderstorms?

South East Essex UK