Residential Surge Protection Using TVSS’s SPD’s Part II

June 7, 2009

damaged modemAn  analysis commissioned by State Farm Insurance found of 5500 detailed claims, more than half of the loss was related to telephone and electronic appliances.

As we become more connected through smart technology, AC power and low voltage or non-voltage carrying conductors become intertwined through the technology. When you think about it, more and more devices have an AC power cord  and a communications port for the transmission/reception of an external signal (video, DSL, etc.). Known as  “multi-port” equipment (AV Receivers, TV’s Modems, Computers, etc.) these devices add complexity to the transient voltage issue by creating additional doorways into the equipment. As we saw  in the AC Ground and Bonding article, external surges can enter the house as easily through the Telephone line, CATV or Satellite Dish as the AC utility. Studies show, even with a TVSS in the AC circuit, micro-electronics embedded in the equipment have failed due to transient voltages passing through the communications link. According to the same insurance study mentioned above, equipment including micro-electronics such as computers, TV’s, VCR’s and Satellite receivers recorded more significant losses than single-port equipment. This is not news to most of us. However, the point to recognize here is that any incoming services that arrive inside the house on a current carrying conductor (copper wire) has the potential to allow a voltage surge into the house and into our electronic equipment.

To make matters worse, having proper surge protection on the AC service and not on non-power related services may actually enhance the opportunity for a fault to occur in the multi-port equipment through surge current.  This  surge current  can create a  voltage shift  at the secondary-port on the equipment producing damage in the equipment. This voltage shift condition can also be rooted to a difference in voltage potential or ground reference at (you guessed it) the service entrance ground. This is the reason why we have seen more emphasis from the standards bodies (National Electric Code and National Institute of Standards Institute)  on the common grounding and bonding of all the incoming services (Telephone, CATV and Satellite TV) found in a typical residence. For this reason, in 1992 the IEEE  recognized this potential fault condition and coined the term Surge Reference Equalizer. Even though the industry has not really picked up on the term nor have they created a specific standard, the  UL1449 listing for this Class B surge protectors is acceptable for the time being.

 Proper Bonding and Grounding  Remain the Key Contributor to Both the Problem and the Solution

If you have read the four articles up to this point, you may think I am beating this subject to death, but grounding/bonding  remains the key contributor to both the problem and the solution. Complete the 8 point check list found in the AC Service Bond and Ground Part II.  If your house is less than 10 years old, it would be a fair assumption that all the incoming services enter near or at the AC service meter. Assuming all the services are bonded correctly as mentioned, you should be in good shape with the Telephone and CATV. For the rest of us, these services could attach any where around the house this also includes Satellite TV Antennas.  If possible, bringing all of these services within 20 feet of the AC Service entrance and attaching them as mentioned will assist in improving the ground system. (TIP: Satellite installations are typically located where they provide the best signal, bringing the ground termination from AC service entrance is important here as well).

Surge Reference Equalizer

surge protector class b 2At this point, we will assume that you have a good common ground with an equal ground reference. With that said you have successfully reduced the risk to multi-port equipment, BUT, both the IEEE and the NIST support the use of the Surge Reference Equalizer. As pictured, it looks like a typical Class B surge protector, but also has ports for communications ( RJ45 terminal, and threaded CATV terminal. With this type of TVSS there will be a PORT-IN and PORT-OUT set of connections.  Consider a Class B surge protector that includes both communication ports and CATV connections collectively in the same product for home theater equipment, set top boxes, satellite equipment, computers and any other mutli-port electrical equipment.  

Additionally Square D has release a whole house model that includes a Class C surge protector and the connections for Telco and CATV services. Tiered protection is still recommended if you decide to follow the whole house approach. (Square D Model SDSB1175C). NOTE: This method of reference equalizer is fairly new as previous practices supported keeping the services segregated until the point of termination, (CATV, Phone) independently until they reach the point of  use or the device that is common (i.e. TV, PC). As you will note, that is how I built my system. This is still an acceptable solution. 

Additional Choices – Surge Protection for Communication, CATV and Satellite:

Telephone Service: Most wire-line telephone service companies provide surge protection. If your telephone service was installed less NIDthan 10 years ago or has been worked on in that time frame you will probably have a NID (Network Interface Device) at the telephone entrance.  Telephone companies typically use “Gas filled arrestors”. Even though you may not have a NID, you probably have gas arrestors  if your phone  has been serviced in the last 20 years. Gas arrestors replace Carbon arrestors as the gas style will defeat the surge without a long term loss in service as they will self restore automatically. Since I built my grounding system before the Surge Reference Equalizer was readily available,  I placed an additional surge suppresor on my telephone line (Channel Vision C-0410). Much like the Telco provided unit it will disconnect the line in the event of a surge then restore it momentarily. Based on the performance characteristics of a Surge Reference Equalizer (SRE), in theory, I may still have a fault occur if my ground reference is not equalized and my Category A, B and C surge protectors are unable to defeat the surge prior to entering any of the protected equipment.  Since the current UL1449 is the only published document and it seems to favor an AC type failure,  for now, I am staying with my current system architecture using the C-0410  surge protection. TIP: You may have communications and/or video services provided by fiber optics. They will not have surge protection as optical services are unable to carry voltage or surge current.  If you are unsure if you have fiber optic services, the NID will have a consumer replaceable battery pack that you were informed about during the installation of the services.

4EDHICCAOT4EQ5CAS0S8SJCAJTJ6C8CATZJ50ECAZ5INCICAHEAI1MCAUYSD7KCAH7U0MDCAW5L3WSCA19XS37CAG3S3RACAVHVBMWCAXWUAI6CAED0UDWCAI9J2UFCAR71UZ8CA65BE4DCAQB2POKCATV and Satillite Services:In practice, the gas style arrestor  is used in these services as well. Because they use coax as a cable medium the arrestor looks a little different but perform in a similar fashion as the communications arrestor.

Theory vs. Science

One of the difficulties with this subject is it is very difficult to test your solution. To replicate a surge equivalent to a lightning strike is not feasible nor recommended. For this reason, surge protection, TVSS’s, SPD’s and bonding and grounding is not as black and white as we would like it to be and neither are the solutions. As you have seen in this article , there may be multiple solutions to the methods I have described. But overall, the method should still retain the same theme.   I have engineered large systems in multi story buildings and spent hundreds of thousands of dollars (not mine) to create the right grounding network  and still had recordable faults, so don’t think you will ever be 100% protected.  

One of the best articles written to date for residential bonding/grounding and surge protection is “Surges Happen”   produced by the Institute of Standards and Technology. This article covers the topic in very simple language and easy to understand instructions.

If you haven’t already, you may also want to read my 4 previous articles; AC Ground and Bonding, Electrical Switches and Outlets, AC Service Bond and Ground Part II, Residential AC Surge Protectors,

Key Inspection Points and Action Items:

  1. Annually check all your TVSS devices to insure the they remain in the protected mode (LED indicator).
  2. Follow the inspection routines as defined in AC Service Ground and Bonding Network by inspecting the mechanical connections and terminations.

In writing this series, it became apparent that I could not cover the subject in 1 or 2 postings. I hope I kept your attention and it made sense. Feel free to comment or send specific questions to Homeownerbob@gmail.com

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Residential AC Surge Protection Using SPD’s and TVSS’s

May 31, 2009

lightningNeither the IEEE (Institute for Electrical and Electronic Engineers) or ANSI (American National Standards Institute) recognize Joule Rating as a means to determine any level of surge protection.

The best way to deal with electrical surges and spikes is to divert them from entering the house in the first place. This is why the external ground system mentioned in Part II is so important. Spikes and surges look for the quickest and shortest path to ground.  Industry Standards recognize that creating a tiered or layered approach to transient voltage  management for your house will provide the best protection, but it’s still no guarantee. Lightning strikes and surges can appear to have their own mind when it comes to seeking ground.  Following the recommendations that I have mentioned in this series of articles will assist in properly protecting  you and your house.

Layered Approach to Surge Suppression

Approaching  surge protection with tiers serves to create layers of  filtering .  ANSI and IEEE acknowledge 3 tiers, A, B and C.  Each level is recognized to provide protection for a defined application. Look at the following drawing to visualize the different tiers and location of the protection device. Class C is located at the service entrance or meter, Class B serves sub-panels and points of distribution (power strips), and Class A provides protection at the source or point of use (POU).

 TVSSv2

Most whole house residential grade TVSS’s  (transient voltage surge suppressor) use MOV’s (metal oxide varistors) for protection. By design, the TVSS does not absorb the fault but divert it to ground. By doing so, these faults erode the MOV’s over time. For this reason, most high quality TVSS’s include some form of “wellness” indicator or failure alarm (red or green LED lamp). Once the MOV’s are destroyed, the lamp indicator is extinguished or in some cases sets off an alarm. Studies show these MOV equipped TVSS’s can last up to 10 years. Granted, this life expectancy is directly impacted by the number of spikes and surges diverted by the MOV’s. So if you live near me in Texas, Oklahoma or places with lots of lightning, don’t count on the 10 years of life. 

The IEEE  recognizes three classes of surge protection and they all perform a defined task, but regardless of the class, all the surge protectors should meet these standards.

  • Listed  with UL 1449 Second addition (not meets, complies or designed to). TIP: If a product is “listed” with UL, Underwriters Labratory actully tested it for compliance to the standard.
  • Comply with ANSI/IEEE C62.41 as it pertains to the class category (C, B or A)
  • SVR rating of 400V or less (probably the most important rating)
  • Per phase rating of 70,000A or less
  • TVSS shall protect against line to line, line to ground  and neutral to ground voltage transients
  • Include visual indicators (red or green LED) for proper operation or failure of the TVSS
  • Class C & B devices shall operate bi-directional and treat both positive and negative impulses, yielding line control and short fliker ride-through. If the Class A does this that’s good too, but more important in the Class B and C
  • In shopping for a TVSS (aka SPD or Surge Protection Device) look for this information on the box or possibly in the fine print with the instructions.

    Surge Protection Devices come in many shapes and sizes at each class allowing you different choices. If you choose to install a Class C unit, you may have to employe an electrician, otherwise  you can use plug-in modules for the other two levels. 

    Class C Whole House TVSS Suppressors for Service Entrance Applications: Intended to be located at the incoming AC service or AC service panel. For various reasons, there are multiple types and styles for Class C residential TVSS’s. Hopefully one of these styles can be integrated into you electrical system.

    8MLB34CAXTULUCCA683WXWCAZ9RMICCAAJD0LLCA2TBUMZCAJP70R2CAQBLV90CAXW8Z0KCAD3SO8UCAWLMVA8CAW85X0MCA09XOTYCAIKMTBACAXK0BG6CAGJA7AICA11C7C0CAZRGZN5CASXME2QMeter Base TVSS: In some municipalities the utility carrier may offer to sell or lease you this type of TVSS. Other than the fact they will probably want to charge you a monthly fee, I like the meter base style. This TVSS is placed in the circuit prior to entering the house service panel. This allows the TVSS to divert any external surge to ground prior to entering the AC Service Panel where a surge could go through the house instead of the intended ground source.   I spoke with my electric provider but they did not offer this service nor would they allow me to supply my own.

     Circuit Breaker Derived TVSS: With this design, the TVSS is wired into the house AC Service panel. Like most, it is equipped KGXLCICAK8YY0ACA4Y6SENCAT00S0QCA8ILWGGCAI4RG93CAPL7N6JCAIOLQEOCA89V8DICADV5D7SCAFP6C2ZCA6SSVLQCACWP20OCA0IU2YTCARFBJFUCAW6A4B2CABBYFDICAZGFPHTCAIU4OGSwith MOV’s and a state of health LED lamps. These styles can be purchased for both indoor and outdoor applications (indoor model pictured). The key here is to keep the TVSS installation as close as possible to the service panel and the connection wire should be as with the short as possible (6″ or less). For my house I also re-arranged my circuit breakers in the panel to allow me to place the TVSS circuit breakers as close to the incoming mains as possible. This is just a little added work to divert the surge as soon as it enters the panel. 

    QO Breaker TVSSAC Panel Based TVSS: Similar to the circuit breaker design previously mentioned. This breaker style TVSS consumes 2 breaker positions to provide panel protection. The advantage of this type is that it connects directly to the bus terminations in the AC Service panel. The disadvantage is that it consumes two positions and you may not be able to locate one that fits your AC service panel. 

    Power StripClass B  TVSS Suppressors for Distribution and Short Branch Circuits: As a classification the “B” type is recognized to serve electrical sub-panels and distribution, meaning a power strip with multiple outlet with a collection of devices to protect.   The Class B is the most common type found in electronics, computer stores and home centers. You will have numerous to choose from. Just remember to use the criteria listed above to  help with your choice. I would not use the joules rating as part of your decision making process.  Belkin surge protector

      Class A TVSS Point of Use Surge Protection Device for Outlet and Long Branch Circuits:  As a Class A TVSS, this device can either be an individual plug-in module (as pictured) or the outlet itself. I have used both and depending on the application the outlet version can be a better choice when you have limited space, such as behind a refrigerator or Plasma TV. Additionally, I found the outlet style more difficult to obtain and more than double the cost of the plug-in style. They both include the proper operation indicator. 

     By this point you should recognize two major points. 1)  Having proper grounding is imperative and, 2) surge suppression goes beyond point of use (POU) devices, 3) implementing a tiered approach is necessary to protect you and your household adequately. 

    Believe it or not…. there is still more. Next time I will discuss specific surge protection for your CATV and Telephone service.

    You may also want to read: Electrical Switches and Outlets, AC Service Ground and Bonding, AC Service Ground Part II,


    AC Service Ground and Bonding Connections Part II

    May 17, 2009

    electricalLightning is responsible for more than $5 billion in total insurance industry losses annually, according to Hartford Insurance Company.

      Here in the Southwest the weather is struggling between winter and spring which brings heavy rains and torrential thunderstorms. These conditions increase the opportunity for electrical surges and spikes. The impact of these storms can cause both personal and property damage. Proper grounding and surge protection can  be your best defense.

    Unplugging electronic devices was the old school method of protecting our electronics, however with more microprocessor based equipment that may be built-in or hardwired it becomes difficult to do that.  This can be good and bad. On the good side, this “smart” technology can allow our washing machines to weigh the clothes to determine how much water to use, to our sprinkler systems determining how moist the soil is before it waters our landscape. On the bad side, all of these electronic devices are highly susceptible to the negative effect of power surges and spikes. Any technology less than 10 years old can easily be a candidate for failure due to technological advances based on micro-processor based technology. With all that said, it becomes very important to protect all of these devices from electrical surges and spikes. Even if you live in an area with very little lightening, or thunderstorms, your equipment is still subject to utility and equipment based electrical surges. 

    Even though most of us recognize electrical surges as they occur from outside sources, (severe storms, etc.) power fluctuations (or spikes)  from utility switching equipment and even equipment within our house have the ability to create power transients that can have an impact.  So, to properly protect you and your house, you may consider going beyond the typical power strip or point of use (POU) surge protector by having multiple layers of protection.  Obviously, equipment such as a Flat Panel TV, computer or audio equipment require point of use (POU) surge protectors but including  Surge Protection at the point of entry (electrical service panel) will also provide protection for items such as dishwashers, HVAC systems, microwave ovens, washers, dryers and so on.    

    tt43kicamiqr72cajlxf3qcaqg2uy9cataa1tgcaozp5xycal1ce1jcanvsd5ycaf7gwszca1aq9vncaubtid9cayql0nrcav7a5t3ca26lasucaabxmn3ca179qr3cagr0p6uca5rqldfca8ochrrProper surge protection cannot be discussed without stressing the importance of  a grounding network for your house. My article on bonding & grounding covers how to identify and inspect your system, but the subject warrants a bit more discussion. The reality of the situation is that your household experiences electrical spikes and surges regularly even without a storm in sight and the source can be any incoming services (Commercial AC, CATV, Satellite TV and Telephone Service) as well as electrical appliances in your house. 

    Both the National Electric Code (NEC) and National Institute of Standards recognize the importance of proper grounding  by providing recommendations and standards to increase this level of protection. Read the following articles before you go too much further. For your house to be properly protected, the integrity of the complete house is essential. Bonding and Grounding, Electrical Switches and Outlets (especially testing of the outlets). TIP:  Any outlet without proper grounding should not be used for any electrical equipment that requires protection even when you have a POU surge protector plugged in.

    Ensure your grounding systems is up to par:

    1. Test all your outlets as mentioned above.
    2. If your house is over 30 years old and the electrical service has never been upgraded, the water pipe may be the only source of ground. Adding a ground rod would be a good idea at this point. Add the ground rod near the electrical service meter and a new wire between the rod and the ground termination bar in the service panel. It’s okay to leave the cold water pipe connection in tack. The grounding schematic  found below is considered a perfect world design. Creating this form of grounding arrangement will optimize your ground system.
    3. Grounding SchematicIf you have a ground rod and it is over 20 years old, it may be time add a new one. Underwriters Laboratory (UL) recognizes standard copper clad ground rod have a life expectancy of 20 years. If the electrical system has not been upgraded, replacing the ground rod will be cheap insurance.  Its perfectly okay to have multiple ground rods connected together in an array. 
    4. National Standards recognize ground systems with less than 5 ohms of resistance as being acceptable. Unless you live in a very dry climate or have known issues, testing an installed ground rod may not be necessary. If you are thinking you need to replace it,  it’s cheaper to just add it than have it tested.OYL94SCAGD0QOUCAYL04A3CAWYLBW6CAAH81G0CA0L2SH0CAHPGADSCAA7UEPWCAR3W6D8CAEFUGXNCAWGM712CAE6Z75SCAHKAUTPCAM64A17CAYGWHLQCAY41LE9CAXSYBESCAAW9HKRCASITYXC
    5. Ensure that all CATV, Telephone, Satellite services are collectively grounded at the same location as the AC service. TIP:  The closer these services are to each other and the shorter the ground wires used to connect them; the better.  Using the proper grounding hardware, the ground wires can be connected together at the ground rod, or you can use a collection device like the one pictured.    
    6. NEVER EVER connect a ground wire or ground rod to a natural gas pipe.
    7. As noted in the Grounding Bonding Post, having all the incoming services enter the building in the same general vicinity is most desirable.  TIP: With existing houses, these services may already be installed. If you are remodeling or building, keep this item in mind as you go through the process.   When the services all enter from different locations, surges may travel through the house to reach the intended ground source. Unfortunately in those type cases, this can increase the opportunity for the surge to follow an unintended path that may include passing through a television or computer.
    8. Following these items will reduce the risk and opportunity for surges and spikes, however damage from direct strikes are nearly unavoidable. 

     Odds Stacked Against You:  Having  a good ground system as mentioned above will protect you in most cases, however there are certain issues that will work against you. Some of the conditions you can change,  some not. Either way you need to be aware of them. 

    1. Tall structure; having the tallest structure in the general vicinity
    2. Having the largest or tallest trees in the area
    3. Large antennas, such as amateur radio
    4. Located near open water
    5. Older vintage building wiring systems that did not include proper or adequate grounding
    6. Living in an area served by aerial electrical, telephone or CATV lines
    7. Living in an older neighborhood with numerous tree’s in the utility easements
    8. A combination of any of the previously mentioned situations

    I know this is a lot of information, but these grounding issues are regularly overlooked until a failure or problem has occurred. If you see the value of this, but its over your head, consult with an electrician about evaluating your system and performing the upgrades for you. My next article will cover the actual surge suppression devices (aka. TVSS). We will see the different classes of TVSS’s, where and how to apply them  and how to recognize a good one.  Look for my next post on Residential AC Surge Protection Using SPD’s and TVSS’s.


    Seasonal Reminder – Spring To Do List

    March 7, 2009

    springSPRING HAS SPRUNG!!  Okay not everywhere. Here in my part of the country the daffodils have been out for about 4weeks. Yep, it got here early, so if your local temperatures are above freezing and the trees are starting to bud, it’s time to move forward… its inevitable. It’s time to fix all those items that broke during the winter months, repair the items that have deteriorated over the last few months and perform a little preventative maintenance around the house. This seasonal reminder  provides a list of items you need to review before the summer months set in. If you need details on what to look for or what to do, click on the link (if there is one) and it will take you to the post that was written on the subject and provide more detail.

    1. Heating/Cooling-Air Filters: Assuming you have a forced air system, change the filter prior to the heavy air conditioning months.
    2. Roofing-Looking For Leaks:  Spring rains are approaching so inspect your roof for leaks, trim away any tree limbs and clean debris off the roof. Look for raised nails and any breaches in the roof surface.
    3. HVAC Outdoor Unit: Get your garden trimmers out and trim away any vines or growth away from the  outside condenser. You should have 18″ to 2 100_0233feet clearance around the unit. Also take your water hose and wash down the outside coils  that may have accumulated dirt. Check the condensation drain that comes from the air handler in the house. Ensure that it is clear of obstacles or debris by pouring water through it.100_02311
    4. Water Leaks: Check all water fixtures and toilets for leaks. Inspect fixture drains for water puddles or loose joints in the traps.
    5. Lawn Sprinklers: Exercise the system. Look for excessive water traveling down the driveway or sidewalks. Inspect the sprinkler heads, look for blow-by and odd spray patterns. Replace or repair the heads.
    6. Exterior Inspection:  Walk around the house, look for rotted wood, peeling paint and other exposed surfaces. Use caulk to re-seal cracks and touch up paint to reseal the surfaces. Replace rotten wood as necessary.
    7. Interior Inspection: Winter dry-out will have caused some surface cracks around doorways and windows. Also  re-caulk/grout any cracks that may have surfaced in the bathroom and kitchen, especially around the tub and shower. These two areas experience the most use and require the most maintenance.  Replace or clean water filters, faucet strainers and vent-a-hood filters in the kitchen. Flush kitchen and bathroom sinks with scalding hot water for approximately 3-5 minutes.
    8. Water Heaters: Tank type water heaters should have their pressure release valve tested (opened and closed). This will also validate the the drain pipe is clear and open.
    9. Gutters and Downspouts: Clean you gutters of leaves and debris. Flush them with water to ensure they flow freely.
    10. Surface Water Drainage: Culverts, waterways, landscape drainage systems should be cleared of debris and overgrowth that may have occurred.100_0206
    11. Windows and doors: Look at the edges where the windows and doors connect to the house. Ensure the caulk is in good shape and add caulk as necessary, indoors and outdoors.
    12. Electrical Service: Inspect the Entrance, Mast and Weather-head. Look for any damage that may have occurred over the winter. Look for tree limbs that may be contacting the entrance cable.
    13. Electrical Service-Smoke Detectors: Clean your smoke detectors of cob webs and change the battery.
    14. Test your security system: Work with monitoring service to validate all the door, window, glass break, and motion sensors operate properly. 

    If you are needing some additional information on one of the topics that I have not written about, let me know and I will put it higher on the list of articles to write. Email to HomeownerBOB@gmail.com


    Electrical Service-Panel

    January 18, 2009

    The electrical service panel would be considered the heart of the electrical system. A properly sized, correctly wired panel will serve the electrical needs of the home for many years. Proper care and inspection will reduce the potential of system level problems and failures.

     

    electrical-service-panel1If you have many of today’s modern conveniences such as a dishwasher, clothes washer, dryer, electric heat and air-conditioning, your service is likely 100 Amps or greater. If your house has anything smaller than 100 Amps, upgrading  your service to 150 Amps or greater is highly recommended. If you have very few of the items mentioned, the inspection covered in this section may or may not reveal immediate problems associated with a small panel, but as you add more electrical devices, you will start to see issues that are discussed in this topic.

    Look at the table below to help determine what level of electrical service panel you may have. Generally speaking, service panels are not well marked to provide you an exact rating number, but the fewer positions the lower the rating. More positions typically equates to larger service. This is all based on the assumption that the panel is supplied with large enough cables in the first place. If you live in an older house, don’t be surprised if you have add-on panels that are used to provide additional capacity, if they are installed correctly there should not be any problems. If you question the cable sizes, have an electrician look at the panel for greater clarity.

     

    servicepanelchart-fullinit_

     

    With our increased dependency on electricity, the minimum acceptable size of AC service panels has slowly increased over the years. If your house is in category A or B with the original AC service panel, upgrading to a 150 Amps or greater can be a wise decision, as adding additional circuits will be problematic. In fact, some insurance companies may not issue or renew a policy because of the fire risk associated with the smaller panels.

    INSPECTING THE PANEL

    With relative ease, and a tool or two, the homeowner can inspect the electrical service panel to identify conditions that may warrant further investigation or repair. Additionally, if you would like to analyze your AC requirements, send me an email and I can forward you an spreadsheet to calculate your AC demand. This will provide you a general reference of demand vs. capacity.

    Visual Inspection: This level of inspection is performed with no more than the door open. No screwdrivers or tools should be required to expose the face of the panel. There should not be any exposed wires at this point. Your service panel should (generally) resemble this picture (for a panel newer than 1960). Look at the general condition of the panel.

    1. The door should open and close without difficulty or obstruction.
    2.  The panel should fit snug to the adjacent wall. No gaping holes around the panel face around the Sheetrock or wall covering. If you find conduit or Jacketed Metal Conduit (JMC) leaving the sides of the panel, this is okay assuming the electrical conductors are not exposed.
    3. With the door open, look for missing knockout where breakers may have been removed. TIP: Home centers have plastic filler plugs to cover these holes. 
    4.  No standing water, corrosion or signs of water in the panel is acceptable. Call an electrician for resolution.
    5. Look at all the breakers for deformation, if they look melted or are no longer holding their original shape, they should be replaced. This can also be an indication the breaker has or is exceeding its limitation.

    Heat and your AC Service Panel: Heat generated by the electrical service panel is an indication of potential problems that may result in an interruption of service. Heat can be recognized in a couple of different ways. 1) by touch or, 2) or digital  infrared thermometer.  If you don’t own a digital thermometer, they can be purchased for a reasonable price ($15 to $100) over the Internet or discount tool supply. The digital thermometer will be referenced throughout HomeownerBOB and its a great addition to your tool box. You will find lots of uses for it.inferred-thermometer

    Before you look for heat issues, try to answer these questions.

    1.  Have you noticed that you regularly trip breakers?
    2. Does it occur at a certain time of the day?
    3. Does it occur when you use specific appliances such as a vacuum cleaner or hair dryer?
    4. Is it the same breaker(s) that have to be regularly reset?

    If you answer yes to any of these questions, it’s a good decision to replace the breaker(s) now. All breakers have a service life and can deteriorate over time due to frequent tripping or heavy loads. Large commercial breakers can be tested and repaired, but it is more economically feasible to replace residential breakers if there is any question of their reliability. Furthermore, this will further the isolation process of the breaker if it continues to trip.

    1. Test by Touch: Without a digital thermometer, you can place a finger on the face of the plastic breakers. TIP Look for temperature differential. If you find an individual breaker noticeably warm, and it has been tripping, you may have an issue, so have the breaker changed out. If you already changed it out and it is still warm, the load on the circuit is probably high. If the breaker has not been tripping, no further action is required. Just make a note in your inspection journal and look for a change from one inspection to the next.
    2. Test by Infrared Thermometer: TIP: Look for temperature differential. If you find 25% in temperature difference between the hottest breaker and the coolest, and it is not tripping, log it in your home inspection journal.
    3. Tripping Breakers: If the breaker has started tripping, replace it first, then try the following trick to resolve the issue if it continued to trip after replacement. TRICK: Identify everything plugged into this circuit and try moving some appliances to other circuits to de-load this one. If you can live with this change, you have solved the issue, no further action is required. If it’s not a convenient arrangement, you may need to hire an electrician to re-associate some outlets to different circuits. This can get expensive, but it will take an on-site analysis to figure it out. Regardless, re-associating the circuit should solve the problem.

    Testing and Exercising Circuit Breakers:Some professionals recommend circuit breaker testing by switching breakers on/off 5 consecutive times once per year. HomeownerBOB considers this optional. If the service panel is over 10 years old and breakers were never exercised for test, cycling them may actually cause some deterioration. TIP: Determine the brand and style of the breakers and buy a couple of the most common sizes (15, 20’s and 30’s are the most popular) and keep them for an emergency. If you choose to exercise the circuit breakers in the future, you will have ready access to a replacements. If the house is fairly new, exercise them if you wish.

    Service Panel and Breaker Caution:  If your service panel is a Federal Pacific brand, some municipalities require them to be replaced. FPE Panel Controversy.

    gfci-breaker GFCI Circuit Breakers:These special breakers will look different than a standard breaker as it includes a test and reset button, just like a GFI (ground fault interruption)outlet. In newer houses the electrician may wire an entire bathroom or all the kitchen circuits as GFCI in lieu of installing individual GFI outlets. You may also use an outlet tester with a GFI  testing feature to trip the breaker. Either way will work but HomeownerBOB prefers to test at the outlet as this allows you to associate the outlets with the breaker. See Outlets and Switches.

    afci-breakerAFCI Circuit Breakers:  AFCI  breakers may look like a GFCI, both will be properly labeled to identify the difference. Arc Fault Circuit Interruption breakers are designed to prevent fires based on an arc flash that could occur in an electrical appliance. Read their full description in US Gov. AFCI doc for more information. Since 2002, the NEC has required these breakers be used with all bedroom circuits. TIP: These breakers can be quite sensitive and may trip for no apparent reason. If your inspection finds no fault, the breaker has been replaced and it continues to trip, you may consider having an electrician evaluate the circuit. Even though HomeownerBOB cannot recommend the removal and replacement of this breaker with nothing other than the same breaker, there have been cases where replacement with a traditional standard breaker has solved the problem without issue. 

    Replacing Breakers: There are many links on how to change out a circuit breaker. Here is just one. Replace a circuit breaker.  If you are replacing your own breakers, they should ALWAYS be replaced with a like-for-like size and rating of the breaker being removed. NEVER up-size a breaker because it continues to trip. If you replaced the breaker because it was hot and it is still hot or it continues to trip. Make a note in your inspection journal. If it starts to trip over the year, follow the testing isolation method described above. The NEC (National Electric Code) allows for residential grade breakers to supply up to 80% of their rating. So in other words, if you have a 20 Amp breaker, the actual measured load should not exceed 16 Amps (1920 Watts) at any one time.


    Electrical Service-Meter Base

    January 10, 2009

    electrical-meter-baseThe mast/conduit will typically penetrate the roof and attach to a meter base. Depending on the area,  the meter base is usually serviced and maintained by the local electric utility. At the meter base, there may be another conduit that feeds into the electrical service panel located here outside the building. It can be different from one utility to the next but typically they will maintain items one and six of the items depicted on the sketch. The homeowner is normally responsible for everything else. Hire a professional licensed electrician to perform any work on these items.meter-base-diagram2

    Key Inspection Points

    Inspect for physical integrity. If there is any physical damage noted that would allow water or varmints inside the enclosure, notify your electric utility.


    Electrical Service Entrance

    January 4, 2009

    100_01491 

    During an extreme weather condition where the loss of electricity is widespread, individual service lines are consider lower priority than lines serving a community or neighborhood. For this reason, your home may be without services for an extended period of time if your only problem is the service entrance cable. Keeping you service cables free from tree limbs and obstructions will reduce your risk.

    electrical-entrance2On the outside of the house, look for the location the electrical service arrives at the house. If you have a large black cable originating from a nearby utility pole, your service is considered aerial in lieu of underground. If you have underground service no routine or inspection is required. For aerial service, typically the utility pole is within 20 to 50 feet from the house. Visually follow the path of the cable to the house.

    Look for a clean unobstructed path in which the cable travels to get to the house.   If there are tree limbs or other items pushing the cable from its natural path to the house, this condition should be addressed. If there has been limbs rubbing the cable, use binoculars to inspect cable sheath to make sure it is still intact. If trimming is required; a minimum of 18″ to 24″ area of free space should encircle the cable. If tree trimming this area has never been performed, this could be quite involved, but after you perform it the first time, yearly inspections and pruning will be simplified. DO NOT TOUCH THE CABLE WITH ANY DEVICE THAT COULD CONDUCT ELECTRICITY. Never use a metal object to move the cable. If you do not have appropriate trimming tools, consider hiring a professional tree trimmer. If you choose to perform the work yourself, only perform the work on a clear dry day. If there has ever been any large limbs fall on the service line, ensure the service line is still a minimum of 10 feet above the ground at its lowest point. If the service wire (drop) is too low, there is usually a reason for it as previously fallen tree limbs may have caused the damage. electrial-entrance31

    A similar inspection of telephone and TV cable (CATV) should be performed as well. Different from the electrical service provider, the cable and telephone suppliers will trim the trees around their service lines between the house and the service poles, but it may be difficult to get them to perform this work just because the foliage is heavy. Typically, they only perform the function if there is degradation in service or they are on site for another reason. In other words, you can wait till it breaks and call them out to fix the problem or you can trim it yourself if the foliage around the lines need trimming. Normally there is no dangerous voltage or high current associated with the CATV or telephone line, but follow the same precautions as with the electrical service.

    Additionally, both the CATV and telephone lines should retain a space cushion of approximately 12″ to 18″ below the electrical service drop in its parallel path to the house. It’s okay for the CATV and telephone lines to touch each other but not the electrical line.

    Key Inspection Points and Action Items:

    1. Visually inspect the electrical service drop for cuts, chips, flakes or bare spots.
    2. Trim trees and shrubs away from the line.
    3. Ensure the electrical line is at least 10′ high at its lowest point.
    4. Repeat inspection and correction process for the CATV and telephone service drops.
    5. Contact the appropriate utility (or electrician) if the the service drop(s) are in need of replacement.