Power Surge

Power surges can come from many sources and I have found that even modern televisions are prone to damage. Being a repair technician I see my share of power related problems. Most television power supplies will have some form of surge suppression built in. But, in practice it has been little help.  Televisions have two primary entrance points for a power surge; one is through the power cord, and the other is through the antenna connector(s), other possible entrances  but not often causing a power surge, will be through the aux inputs.

The impression I have with our customers is that they believe that lightning has to hit their house in order to have a power surge. That could not be further from the truth.  A Lightning strike miles away can cause a damaging spike.  It can strike either the power lines or the cable lines.  Another myth is that lightning is the only cause of power surge damage.  Large electric motors can generate electrical spikes on transmission lines;    An electric motor and an electric generator are basically the same type of device,  if an electric motor in a factory is spinning and the flow of kinetic energy in the machinery is turning the motor instead of the motor turning the machinery,  that motor will become a generator,  causing a back flow of electricity into the power lines. This inductive loading is called reverse emf. This same thing can be seen to a smaller degree with all appliances in your house that use electric motors. Some manufactures will try to shunt some of this excess energy to prevent this effect. But those components can fail and the appliance will still appear to be functioning correctly, but it will be pushing spikes back into the electrical system. Another form of electrical surge would be from disconnection or reconnection of electricity to a house from the transmission lines outside.  What I have mentioned above is only a short list of possible sources for electrical surges

                Recently our shop had seen a plasma television that was struck by lightning. The surge came in through the antenna.  Since this TV was used in a unique manor it had to be fixed.  No substitute was available. We ended up replacing every board except for the power supply board, including the plasma display it’s self.  The cost of repair was more than the original cost of the television. Normally we would have replaced it but like I mentioned before it’s unique use warranted the extreme repair.


                What can you do to help prevent equipment loss due to power problems?

1.)    Your first line of defense is your house, check to make sure your earth ground is good and the wire running from your electrical box to the stake in the ground is in good condition.  I suggest even pulling on the wire connected to the stake, it should be strong.  If you see excessive corrosion, replace the ground stake or the bolt connecting the wire to the ground.  Also check the cable wire coming into your house, your cable company should have a connector outside with a ground strap going to your ground stake, this wire is the one I see fail most often.

2.)    Get a good surge suppressor for your equipment.  Don’t be fooled by a suppresser costing you  5 or 10 dollars.  These are worthless, they will usually only have a mov or other such inept device in them. Get a good suppresser that will detect current balancing(Transient current). This type will test the current going in and the current returning (similar to a GFI) and it can sense when the current is out of balance and react very quickly to the event.(picking and choosing a good surge suppressor is beyond the scope of this document I might post about this later)

3.)    Pay attention to your surge suppressor.  Most good suppressors will have an indicator light telling you when it is no longer protecting your equipment. This usually means that it has sacrificed it’s self to save your equipment. This may have been a  silent occurrence that is easily missed. So periodically check to see if the warning light is on.

4.)    Make sure your third prong ground (the round one) is connected correctly and that your house is wired correctly for that ground to function right. Most good surge suppressors will have an indicator on it letting you know if the ground is working properly.  If it is not,  correct the problem, or the suppressor will not function properly.

5.)    Read; educate yourself by reading articles and asking questions. The more you know the better you can prevent that big investment loss.


I have a 42 inch plasma screen Philips TV that was the victim of a power surge two nights ago. The TV is two years old and cost 800 bucks when I bought it. Is it possible to fix a TV after it has been zapped by a power surge? Or am I looking at a total loss?

If it is indeed a zero-sum issue, the federal government provided, as states cut, then the effect of the stimulus is zero, unless you look at debt obligations. In this case, the stimulus was not zero,Debt Management but negative by the fact that the federal government owes money.

If it is indeed a zero-sum issue, the federal government provided, as states cut, then the effect of the stimulus is zero, unless you look at debt obligations. In this case, the stimulus was not zero, but negative by the fact that the federal government owes money.Debt Management

yes, but it can be costly if it came in through the power cord that is your best chance, it may require a new power supply. if it came in through your cable it can spread everywhere and will usually ruin more than just one board. expect a minimum of a $200-$300 repair.

Check this company out. I stumbled upon this website and they claim that by using their gadget, your equipment and also the user will be safe from lightning zap. Link: www.cal-lab.com.

I stumbled upon this company and they claim that their gadget can help to safe your equipment and also users from lightning ZAP. 3w.cal-lab dotcom


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