Power surges through HDMI ports

Discussion in 'General Electronics Chat' started by guyrelax, Aug 28, 2016.

  1. guyrelax

    Thread Starter New Member

    Aug 28, 2016
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    I gutted my house over the past year and have been experiencing power surges that blow out the hdmi ports on my tv and stereo. It's happened 4 times. I've consulted an electrician, who installed a whole house surge protector. Well, despite this, another one blew out yesterday. It happened when I shut down the electric to install a switch. When I turned it back on my the port was blown. I'm at a loss of what the cause is and how to resolve this. I've also called the power company and had them check things on their end as well as my meter. All is fine there.

    Does anyone have any ideas? The electrician doesn't know the cause either...

    Thank you
     
  2. KeepItSimpleStupid

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    Mar 4, 2014
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    The whole house surge likely isn't going to do squat.

    Not knowing EXACTLY what you have and how it's hooked up is going to make this really hard.

    One POSSIBLE scenero is a bad outlet strip where your components are plugged in. Another is a bad outlet. I've experienced both in a work setting. An outlet strip with one outlet with a bad ground took out computers, created a 60 VAC potential between grounds and caused sparking.

    One very rare an odd incident was because of defective outlets. Ground was only by pressure and when two plugs were used in "defective outlets" there was the possibility that the ground would let go. We had 420 potential bad outlets that needed replacing.

    So, take a look at the differences in ground between outlets that you think are grounded properly. Also check the TV cable shield.

    I had determined that there was about 60 VAC between grounds. When the outlet was taken apart, we could see the issue.
    The Electricians were clueless as to how to detect a failed outlet.

    If you had a surge protector at your TV, it still won't help. Two power outlets where the HDMI devices are plugged in are suspect. If your using an outlet strip, that's suspect too.
     
  3. AlbertHall

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    Jun 4, 2014
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  4. guyrelax

    Thread Starter New Member

    Aug 28, 2016
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    Thanks for your reply. I don't believe its the strip, as I've changed the strip and the problem persists. I believe the issue is related to the current going to that wall. This is the only area I've notice surge issues. Just where my tv, stereo, and cable box are plugged in. Initially I noticed that when I ran the saw in my basement from one of the basement outlets it would spike that area where the tv is. It blew out my cable box. So, I stopped using that outlet. Then I noticed when there were storms it blew out hdmi's. I then installed whole house protector. Now still happening. Is there something I can test to narrow down the issue? Should I buy a multimeter? Is there a device that will measure surges I'm getting?
     
  5. AlbertHall

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    Is the ground in the outlets correctly grounded?
     
  6. guyrelax

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    Aug 28, 2016
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    The surges don't indicate a ground fault, and they appear to be wired normally.
     
  7. KeepItSimpleStupid

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    I'll come back with what I might use to troubleshoot, but without that, I might consider re-wiring. I'll assume your in the US.

    By re-wire, I mean use pigtails in each outlet and not the poke the wire in method. I have no idea what you used. My favorite is to use the Ideal term-a-nuts. http://www.idealindustries.ca/products/oem/twist-on/term-a-nut_pigtail.php

    A reminder, that if the box is metal, it has to be grounded too.

    So, first, lets say you can identify the path of the wire. You would use black and white term-in-nuts with a fork end for the black and white wires in each box. The fork terminal goes to the outlet.

    Wiring ground is the tricky one.
    1. Plastic box: green term-in-nut to ground wires, and fork to ground screw on outlet.
    2. Metal box (new style with tapped hole for ground screw) Use a fork to stripped wire green pigtail. Attach the term-in-nut to the grounds from the Romex(s) and the green pigtail. You'll have a fork on the term-in-nut that will attach to the ground lug on the outlet. The other fork will be grounded to a green ground screw that will fit the tapped hole (these are purchased separately).
    3. Metal box (old style. no taped hole) Much harder. You have to use a ground clip. Solid green wire to fork pigtail. Will explain better, if needed.

    So, now you have a solid connection for white, black, and green that will be independent of any single outlet issues.

    So, I'd "blanket replace" all of the outlets on that circuit and re-wire as above.

    I need some more time to think.

    There's some good things here and some possible bad things too. The important thing is to twist the wires together. The green term-in-nut to fork would make that install go quicker and nicer.

    Since the cable is involved that has to be looked at too as well as the voltage drop across the breaker terminals which you may not be comfortable doing.

    ==

    Describe in somewhat detail how the cable enters the house and what it connects too.
    There should be a grounding block and a ground wire. That's what I'm interested in.
    You may want to take pictures.

    ==

    You might want to pull one of the 120 V outlets out of the box and take a picture.

    how much did you pay for the 120 V outlets.

    ==

    I had an issue which I think could be similar to yours, but I had the right tool. Because the ground wires were not tightly twisted together, that ground was flakely. Finding it was tough, but much easier because I knew the path and had the right tool. This http://www.licensedelectrician.com/Store/ID/SureTest_Analyzers.htm thing.

    So, I am suggesting a "bad ground" in your parallel string of outlets. I also had a TV issue nearby, but tit was the TV distribution amp. The ground effectively was made through the RG-6 shield and not the ground wire. Visually the ground looked OK in the bad outlet.
     
    Last edited: Aug 30, 2016
  8. guyrelax

    Thread Starter New Member

    Aug 28, 2016
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    So here's what my outlet looks like when I just pulled it out. Based on the video you sent, not sure what to do with this given it has four connections. Can't say I understand everything you're telling me about the voltage drop or 120v outlets.

    Regarding the line coming into the house it's just a wire coming off the pole wired to the house goes down a tube and right into my foundation which goes into the back of the box. Should I be looking for something else?
     
  9. KeepItSimpleStupid

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    I'd actually flunk you for inspection, because I don't like the way the grounds were done.
    Generally, you really have to twist the grounds tightly together for a few inches and then pigtail attach to the ground screw to do it right. The 30-3480 would also work. The grounds get twisted along with the 30-3460 and a wirenut applied and the fork terminal gets connected to the outlet.

    What happens is that the copper develops an oxide, so even twisting doesn't make a good connection. The wirenut makes a gas tight connection at the point of contact, so now oxidation isn't a problem.

    Let's just look at the ground wire for now:
    Here https://www.worldelectricsupply.com/Images/img/783250/1293608.pdf the green termanuts (30-3380 pkg of 10) just make it a lot easier. Look at the diagram as to how they are used.

    So, you would twist the bare wires together at least an inch or more with lineman's plyers. Trim the end. Put a green termanut on the end of the twisted wire and attach the fork terminal to the green screw. The pre-twisting is IMPORTANT.

    That was exactly my issue - twisted, but no wirenut and attached to the metal box.

    If you were to use them on the white and black wires, you would remove both. Twist the white wires together and trim. use a white termanut. Do the same for black. Now, the outlet wiring is totally independent of the source. There's a smaller piece of metal whose cross-sectional area is not that same as a #12 or #14 and this raises the resistance of the power legs. The "right way" is to "pigtail" behind the outlet. The Termanut method makes it much easier. They are about $25 USD for 25.

    So, that's a $75.00 investment assuming 10 outlets and re-doing black , white and green.

    The Ideal Sure-test can help identify which connection is bad, but that's like $300.00 USD.

    How close to Philly (I don't live there) do you live?

    ==

    I was asking how the CATV connection enters the house and what it does when it gets there.

    ==

    I actually have Antenna with about 12 possible TV locations throughout the house. All home-run to a central distribution point. There is a huge amount of amplification in 2 places (mast and central distrbution) and tap distribution, not splitters. I'm in another league.

    ==

    INHO: Your grounds suck in my opinion and high current loads (saw) could have issues.

    ==

    For someone not having a clue, the possible test equipment I would like to have would be:

    1) A power line disturbance monitor (It's rentable)
    2) The Ideal Sure-test device which I do have.
    3) A wire tracer such as http://www.amprobe.com/Amprobe/usen...ed-wire-tracers/AMP-AT-7020-kit.htm?PID=79193
    4) Multimeter. or $6.00 it's worth having: http://www.harborfreight.com/7-function-digital-multimeter-90899.html

    BTW, I worked with currents as low as 2e-12 Amps, currents as high at 3000 Amps, Voltages as high as 100 kV (10 kW) and 1000 W into 50 ohms at 13.56 MHz. I also had to measure both v and i where V was below 0.6 V and I was below 10 mA.
     
  10. KeepItSimpleStupid

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  11. KeepItSimpleStupid

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  12. KeepItSimpleStupid

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    If that cut-out for the outlet is evidence of your carpentry skills, then you need to apply that same sort of meticulous effort into wiring. The real reason why I'm promoting the Termanuts is because it's easy, quick and in my opinion better and significantly faster.

    When a bedroom was re-painted, all of the outlets went to tamper-proof. These are outlets where you have to insert something in both sides in order to make the connection. Kids can't stick stuff (key, coat hanger) in one side. I upgraded from 2 wire outlets to 3 wire outlets and the Termanuts definately made it easier especially when the box and the outlet both needed ground.
     
  13. KeepItSimpleStupid

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    Last edited: Aug 31, 2016
  14. KeepItSimpleStupid

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    So, there are a few more things I want to add:

    Pigtailing:

    Note: No ground connection made to the outlet and it's a metal box. Not good.

    Pre-twisting: http://www.mikeholt.com/forum/Forum1/HTML/005609.html
    The Wago push-in variety works too.

    Note that this is a profession electrician;s forum, thus it has more clout than Joe's Youtube video.
    The general gist, is that the electricians prefer twisting, but some some manufacturer's say either will work.

    You have two basic problems:

    1) Your not allowed to have more than one wire on a screw. Your ground. The green wirenuts with a hole is one solution, but one ground wire has to be significantly longer. You need about 6" outside the box.

    2. The wires don;t have enough loop. You need to cover three sides.The loop has to be clockwise so the screw pulls the wire toward the center instead of loosening. I can see the evidence of problems on one of your white wires. Create the loop beforehand. Large needle nose works best for me.

    Pigtailing:
    a) It;s a way to connect a single wire to a screw like in your case with the grounds. It's also a way to remove the effects of a damaged outlet and you CAN work on the circuit live for those into that sort of thing.

    I think there is sufficient evidence to suspect poor wiring practices as a potential cause especially since it happened after remodeling. A whole house surge suppressor will do nothing in this case. They are a good idea.

    Two possibilities here:

    1. The ground connection could be poor and the path end up being through the coax CATV cable. This raises the ground potential because it's not low Z. The 5V on the HDMI cables is not tolerant of this at all.

    2. Loose connections on the neutral of Hot legs because of poor connections on the screws. Arcing possible.

    Other issues are surely possible, but this is the area you disturbed.

    The saw may be another problem or another location.

    Voltmeter:
    It does have a limited application here. Where I could be used is determining the voltage difference between two grounds (coax & outlet) for instance, Neutral and ground differences and the drop ACROSS the breaker. The Sure-Test has a better ability to evaluate bad connections. It's also one of the you can tell if it's bad, but can't tell if it's good kind of things.

    Temperature is a variable that can often be overlooked.

    IR Camera: The ones that take pictures could be another useful tool.

    Wire Path:
    Knowing the wire path would be very useful.

    You have the circuit(s) identified and the history and inspection (me) revealed issues because I know what to look for. No, I can't be 100% certain that it's your problem, but it's "a problem".
     
  15. KeepItSimpleStupid

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    I got an email back from Ideal:

    "Unfortunately, our Term-A-Nut product line was made obsolete several years ago, and we did not replace it."

    Just my luck. I like weird stuff that works.
     
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