User Tag List

Results 1 to 10 of 10

Thread: CABLE BOX EXPLOSION NEAR METER

  1. #1
    Join Date
    Apr 2017
    Location
    Florida
    Posts
    63
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    CABLE BOX EXPLOSION NEAR METER

    If you notice next to this metered box there existed a DMARC where the underground feeder for XFINITY came into the home. That dangling thing hanging from the metered box is where the connections unionized. Do you think that this was due to a lightning strike and because of the poor bonding of our copper ground to the metered box not being where it should that this caused this?

    Let me know your opinions as to how you think this happened.

    Click image for larger version. 

Name:	image1.jpg 
Views:	249 
Size:	146.1 KB 
ID:	18544Click image for larger version. 

Name:	image2.jpg 
Views:	270 
Size:	144.4 KB 
ID:	18546Click image for larger version. 

Name:	image3.jpg 
Views:	253 
Size:	150.1 KB 
ID:	18545

  2. #2
    Join Date
    Jun 2012
    Location
    NW Ohio
    Posts
    1,184
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    First glance looks to be lightning strike damage, if there was a open neutral on the utility side I would expect to see some melting of the jacket on the coax or its grounding wire. Speaking from experience.

  3. #3
    Join Date
    Apr 2017
    Location
    Florida
    Posts
    63
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by mopowr steve View Post
    First glance looks to be lightning strike damage, if there was a open neutral on the utility side I would expect to see some melting of the jacket on the coax or its grounding wire. Speaking from experience.
    If its grounded to that meter why would an open neutral cause this, wouldn't it dissipate to GEC that is also in the box?

  4. #4
    Join Date
    Jun 2012
    Location
    NW Ohio
    Posts
    1,184
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Only when a coax comes from utility poles does it lend itself as a parallel neutral path via the shielding of the cable. If utility neutral opens due to corrosion or damage then high currents will use the shield to return current back to transformer. These higher currents often times will melt if not start a fire on the coax and/or its grounding apparatus. Ground rods will never be able to sink enough current (due to ground resistance) to keep bad things from happening.

    Since it looks to have blown the box off the wall, I would say a splitter grenaded durring a strike.

    Lightning is the resulting arc of two charges. Charges so great that it will arc across miles of air space. No little POS in a box has a chance of survival in a direct hit.
    Last edited by mopowr steve; 09-20-17 at 09:18 PM.

  5. #5
    Join Date
    Jan 2011
    Location
    United States
    Posts
    9,380
    Mentioned
    1 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by Cybatrex View Post
    If its grounded to that meter why would an open neutral cause this, wouldn't it dissipate to GEC that is also in the box?

    More current will flow on the COX shield then the grounding electrodes back to the POCO due to the COX shield having a lower resistance. Unfortunately something like 18 gauge wire isn't going to handle 40 amps like a 4/0 neutral- so a LOT more I2R losses.

    Here is a "milder" version in that no fire started:

    https://www.electrical-forensics.com...n-Neutral.html
    Our comedian shamelessly joked about a blackout. Talk about dark humor.

  6. #6
    Join Date
    Jan 2011
    Location
    United States
    Posts
    9,380
    Mentioned
    1 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by mopowr steve View Post
    Only when a coax comes from utility poles does it lend itself as a parallel neutral path via the shielding of the cable. If utility neutral opens due to corrosion or damage then high currents will use the shield to return current back to transformer. These higher currents often times will melt if not start a fire on the coax and/or its grounding apparatus. Ground rods will never be able to sink enough current (due to ground resistance) to keep bad things from happening.

    Since it looks to have blown the box off the wall, I would say a splitter grenaded durring a strike.

    Lightning is the resulting arc of two charges. Charges so great that it will arc across miles of air space. No little POS in a box has a chance of survival in a direct hit.
    Not saying it is- but could also be 7000+ volts getting on the shield from a primary falling into the phone lines.
    Our comedian shamelessly joked about a blackout. Talk about dark humor.

  7. #7
    Join Date
    Jun 2012
    Location
    NW Ohio
    Posts
    1,184
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by mbrooke View Post
    Not saying it is- but could also be 7000+ volts getting on the shield from a primary falling into the phone lines.
    I agree, It was just based on first assumptions.

    Though now I see he is from Florida and that is quite possible with the recent hurricane winds.
    Last edited by mopowr steve; 09-20-17 at 10:14 PM.

  8. #8
    Join Date
    Jan 2011
    Location
    United States
    Posts
    9,380
    Mentioned
    1 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by mopowr steve View Post
    I agree, It was just based on first assumptions.

    Though now I see he is from Florida and that is quite possible with the recent hurricane winds.
    Not to worry- I myself am also assuming. Could be any of those 3 things.
    Our comedian shamelessly joked about a blackout. Talk about dark humor.

  9. #9
    Join Date
    Apr 2009
    Location
    Williamsburg, VA
    Posts
    6,042
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Pretty sure it was hit from a blast of an Illudium Q-36 explosive space modulator... or lightning for those who still believe in 21st century conspiracy theories.
    Electricians do it until it Hertz!

  10. #10
    Join Date
    Jul 2013
    Location
    Boston, Massachusetts, USA
    Posts
    87
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by JFletcher View Post
    ...Illudium Q-36 explosive space modulator...
    For those of you who didn't immediately catch the reference to the classics...

    http://evil.wikia.com/wiki/Illudium_...pace_Modulator

Tags for this Thread

Posting Permissions

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