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A permanently installed surge protection device

Surge Protectors

Dear Mr. Electrician:  What are the best surge protectors that will protect my computer from lightning and how do I install it? Answer: Methods to install whole house surge protectors vary slightly between devices, and the main electrical panel.  However compared to other electrical wiring tasks installing a surge protector on your main electrical panel is relatively easy, though hazardous because of the live electrical components that you have to work around.  NOTE: Text links below go to applicable products on Amazon and EMP Shield. Finding the best surge protectors that will protect your computer from lightning will involve looking at the various specifications of the many brands of surge protection devices.  In addition to surge protection, consider a device that also offers protection from Solar Flares and Electromagnetic Pulses, both of which can be harmful. Do some homework before making a surge protector purchase.  Read reviews from other purchasers, compare the product ratings, check the price ranges for your budget. Read the manufacturer's installation instructions before purchasing.  Many installation instructions are available online. TYPES OF SURGE PROTECTORS A type 1 surge protection device is rated for the line side of an electrical service before the main disconnect.  This type would most likely be installed by the power company. A type 2 surge protection device is rated for the load side of an electrical service after the main disconnect.  This is what would normally get installed inside of, or attached to your main electrical panel. A type 3 surge protection device is typically the point-of-use plug-in modules or power strips, and surge receptacles.  They must be at least 30 feet or 10 meters away, as measured by the wiring distance from the main electrical service.  If less than 30 feet they should also be rated for type 2. A type 4 surge protection device shall only be installed by equipment manufacturers on, or inside of their distributed appliances and machines. INSTALLATION OF SURGE PROTECTORS In my area surge protectors installed in a main electrical panel are required to be inspected by the town's electrical inspector.  An electrical permit must be applied for at the building department.  I submit a copy of the surge protector installation instructions with the permit application. If it is a complicated job or there are unusual circumstances I will also submit a typed, one page "Scope of Work" briefly explaining the planned installation and the materials to be used. If there is something that the inspector doesn't like, I prefer to know about it in advance rather than after the job is done.  Surge protection device installations are covered by article 242 in the 2020 National Electrical Code (NFPA 70). When working with electricity safety is paramount and precautions should be taken.  Do not wear any jewelry including watches and rings, tie back long hair, use insulated tools, and cover exposed bus bars.  Read my post on safety. Shutting off the main circuit breaker will help, but I am sometimes reluctant to do that on older panels because there is a possibility that the main circuit breaker will not turn...
The Telephone and Cable TV Demarcations were Grounded to an Old Pipe

Lightning Protection For TV and Telephone

Dear Mr. Electrician:  What can I do for lightning protection for my TV and telephone lines?  My neighbor was blown out of her chair when lightning hit her TV.  How can I prevent that from happening to me? Answer:  There is no 100% full proof method of stopping a lightning strike from doing damage.  However several things can be done to prevent or reduce the damage.  Basically everything electrical needs to be properly grounded and bonded in such a manner as to provide a good direct path for lightning to flow to the earth. The photos below depict an actual job of mine correcting the grounding for a 1940's single family detached house. Article 250 in the National Electrical Code concerns grounding and bonding.  Some relevant sections are: 250.8, 250.52, 250.90, 250.94, 250.104.  Also read article 800.100 on grounding communication circuits and 820.100 which concerns the grounding of cable TV systems.  NOTE: Some text links below go to applicable products on Amazon or EBay. LIGHTNING PROTECTION FOR POWER, TV, TELEPHONE The above photo depicts how I found the TV and telephone lines grounded.  It turns out that this pipe was not connected to anything.  It was in the ground only a few inches and contained a piece of cut electrical cable, the remains of which is protruding from the pipe.  Needless to say, this would not be adequate protection if lightning were to strike. The telephone demarcation point and the cable TV demarcation terminal both need to be bonded to the grounding electrode conductor for the main electrical service.  Newer electrical installations have an intersystem bonding termination for the grounding conductor from the telephone and cable TV to connect to. On older houses the telephone and cable TV grounding conductors are sometimes connected to an existing ground rod, or have their own ground rod, or are connected to the grounding electrode conductor. EMP Shield Makes Excellent Surge Devices That Protect From EMI Pulse  Above was the existing ground connection for the cable TV service to the house.  I installed a new #10 copper wire and clamped it to the grounding electrode conductor which was connected to the water pipe inside of the house. The copper wire for grounding TV and telephone must be no smaller than #10 AWG.  #8 wire would probably be too big for most demarcation terminals. Additionally all interior metal piping must be bonded to each other with jumpers around water meters, water filters, and other devices whose removal would interrupt ground continuity. The hot and cold metal water pipes must have a jumper between them.  This is usually done at the water heater.  Although the code requires gas pipes to be bonded, some local areas do not want that.  Best to check with your local building department about bonding the gas pipe. The arrow in the photo above indicates the existing grounding terminal on the original telephone demarcation point.  It was still active with it now being fed from the new outside telephone demarcation box.  The existing ground wire was attached to a water pipe at a sink...
Ground rod with acorn clamp and wire

Grounding Electrode System

Dear Mr. Electrician: How do I install a grounding rod as part of the grounding electrode system for my house?  An electrician told me that the grounding electrode system for my house did not have a good grounding rod and gave me a ball park price to fix it up.  Why do I need this and what is involved with fixing or installing a grounding rod? Answer: To install a grounding rod some tools and muscle will be needed.  NOTE: Some text links below go to applicable products on EBay, EMP Shield, or Amazon. A grounding rod is a very important component of the electrical wiring in your home or place of work.  It is part of the grounding electrode system for voltage stabilization and lightning protection.  A ground rod is also referred to as a grounding electrode or anode.  It is required by article 250.53(D)(2) in the National Electrical Code. The power company has their power transformer grounded with a grounding rod.  If the neutral conductor from the transformer to your house ever got disconnected, the return current would travel through the earth to get back to the transformer.  In addition, when lightning strikes on or around your house the rod creates a path for the high voltage electrical charge to go directly to the earth and avoid causing damage to your home. Whenever you hear of someone's house getting struck and damaged by lightning it is usually because the grounding electrode system was deficient. The grounding electrode system consists of a wire or two that originate on the grounding terminal in your main electrical panel or disconnect switch.  From there the wire(s) will connect to the home's water pipes and to one or more grounding electrodes. The grounding electrodes can be ground rods, concrete encased rebar, copper plates, copper wire in the footings, concrete embedded steel or other means that provide an approved electrical path to earth.  See article 250.52(A) in the National Electrical Code. GROUNDING ELECTRODE SYSTEM The main grounding electrode connection for many houses is at the metal water pipe at the point where it enters the home before the water meter.  Look at this area and you should see a copper or aluminum wire; bare, insulated, metal armor jacketed, enclosed in conduit, or taped green.  It should be connected to the water pipe using an approved ground clamp.  The connection should be tight and free of corrosion. The ground clamp in the above photo is attached at the point where the water pipe enters the basement.  An armored grounding conductor requires a ground clamp with an extra clamp on it for the armor to be secured with. If the ground clamp and wire appear corroded or feels loose you should remedy this right away.  A new ground clamp costs only a few dollars and can be purchased at any electrical supply company and at many home improvement stores.  You will also need some emery cloth or sandpaper to clean the pipe. A good precaution when doing this would be to shut off the main circuit...