Electrical Switches and Outlets

September 17, 2011

light-bulbLight Switches and outlets are taken for granted by providing endless amount of light and electricity at a moments notice. With proper care, these electrical elements will serve you and your house for 20 years or better. 

For the most part, we do not consider these items a problem until they are broken or when failure occurs. However, recognizing conditions than can be resolved today will allow you to fix the issue on your own schedule and ensure adequate safety to you and your home. We all know that failure typically won’t occur until you really need it. So take a look at your electrical outlets and switches today, you may be surprised to find that some of them are starting to show indications of wear that will eventually result in failure.  Replacement or repairing them now will ensure uninterrupted service.

Light Switches: This inspection involves visiting every light switch in the house. Go through each room, one at a time.

  1. Standard Light Switches: Operate every light switch in every room. It should operate smoothly. If it is warm, makes noise, won’t stay in the on or off position or feels mushy, it should be replaced.
  2. Dimmer Switches: There are different styles of dimmer switches,  they include standards/with secondary sliders, full sliders and rotary switches. Compared to standard light switches, it is not uncommon to find dimmer switches warmer than ambient. This is normal. Operate the switch through its full range. It should transition from off to 100% (on) smoothly. Some switches may have clicks or notches in the transition from 0% to 100%. If the light interrupts  or flickers during transition from off to 100% the switch should be replaced. TIPDimmer switches and CFL (compact florescent lights) don’t mix unless the switch and bulb is rated for it. This improper switch/bulb combination may act like a bad bulb or switch. 
  3. 3-way Switches: Are defined as two switches with one light circuit. Either switch on this light circuit should be able to turn the light on or off no matter the position of the other switch.
  4.  4-way Switches: Are three switches with one light circuit. Any one of the three switches should work the same as the 3-way switch and should operate the lights regardless the position of the other two switches.

TIP: If the 3&4 way switches do not operate as described, they could be bad or wired incorrectly. It is not unusual to find a 3 or 4 way switch to be previously replaced and not re-wired correctly. See Wiring a 3-Way switch or Wiring a 4-Way electrical switch

Electric Outlets: This inspection involves visiting every electrical outlet in the house.  Electrical outlets are very durable and can last a life time, however the excessive wear and abuse can cause damage to them.c140_product1

  1. Testing: Test each and every outlet to validate voltage and polarity. Purchase a low cost outlet tester much like the one pictured to the right for this inspection. They are self explanatory in their use. Generally you plug them in the outlet and they will provide a self check set of lights that will provide a go-no-go indication. TIP: Make sure you check both outlets on the receptacle as they can be wired separately.  An outlet can fail a test and appear to work properly. The three most common failures are, 1) reversed polarity, 2) open ground, 3) open neutral, 4) Hot open.
  2. Reversed Polarity: Hot and neutral are terminated on the wrong connectors. The outlet may still appear to work correctly. 
  3. Open Ground: The ground circuit is not complete. This usually happens when a grounded type (3 holes) outlet was used to replace a faulty 2-wire receptacle. TIP: Even though this outlet will appear to be working properly and will not cause an issue when using a lamp, this open condition can create issues with electronic devices such as computers, TV’s or stereo receivers.
  4. Open Neutral: Similar to Open ground.  TIP: Even though this outlet will appear to be working properly and will not cause an issue when using a lamp, this open condition can create issues with electronic devices such as computers, TV’s or stereo receivers.
  5. Hot Open: The outlet will be dead.
  6. Receptacles: 2 prong vs. 3-prong outlets were prevalent in houses built prior to 1965 and without an adaptor, you will not be able to properly use a plug cord with 3-prongs. The NEC code changed around 1965 requiring grounded outlets be part of new construction. If your house was built around 1965 and you find 3 prong outlets or a mix of both and the wiring was not upgraded, the tests performed in item 1 will reveal those problems for you (typically open ground). Even though the receptacles may appear to work properly, ghost problems may occur. If your electrical system is based on a a 2-wire system, 2 wire outlets and adapters yellowstone-0111are still considered acceptable. However, proper grounding for today’s electronics may not be compatible and rewiring your house may be considered.   
  7. Physical Damage: Inspect each outlet for physical damage. If the outlet or the face plate is damaged, they should be replaced.
  8. Warm Outlets: If the outlet feels warm to the touch, the outlet or the wire connection may be faulty. Replacing the outlet should resolve the problem. Purchase a higher quality version of the same receptacle (about 3 bucks) and used the screw down terminations. For more detail testing of this condition, see the article on Warm Outlets
  9. Overloaded Outlet: Most residential outlets are rated for 15 Amps maximum. Installing an excessive amount of electrical devices can cause problems. TIP: In these occasions where you need more outlets from the same receptacle, use a fused power strip. The power strip will include a fused breaker on the device. If an overload occurs, it will trip and protect the wall plug and the circuit from damage.
  10. GFI (Ground Fault Interruption) Outlets: GFI outlets are found in newer (or remodeled) houses. Typically GFI outlets will be found in the kitchen, bathrooms, garage, outside outlets or areas where the homeowner may be exposed to water while using the outlet. GFI outlets look a littleoutlet different and should be labeled as such and will have a self test button. The test button should disable the outlet and expose a reset light or button. Press the reset button and power should be restored. If the outlet does not disable and reset during the test, it should be replaced. In some cases, GFI outlets may be wired together and will cause multiple outlets to be disabled at the same time. TIP: These additional outlets may look like regular outlets but SHOULD be labeled as GFI, but don’t be surprised if they are not. Additionally the controlling GFI outlet may or may not be located in the same room.

Key Inspection Points and Action Items:

  1. Inspect and operate all electrical switches to ensure they operate properly
  2. Inspect and test all outlet using an outlet tester.
  3. Replace or repair the outlets and switches as necessary.
  4. Read my article on Warm Outlets.
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Wall Outlets Feel Warm?

September 17, 2011

According to the United States Fire Association (USFA) Electrical fires in our homes claim the lives of 485 Americans each year and injure 2,305 more. Some of these fires are caused by electrical system failures and appliance defects, but many more are caused by the misuse and poor maintenance of electrical appliances, incorrectly installed wiring, and overloaded circuits and extension cords.

A day doesn’t go by that I don’t get a comment on the webpage about warm or hot electrical outlets.  Before we get into the guts of the issue, lets define what most (residential) electrical branch circuits are designed to provide.

NEC 210-23  15 and 20 Amp branch circuits: …The rating of any one cord- and -plug connected utilization equipment shall not exceed 80% of the branch circuit rating. Furthermore… the total rating of equipment fastened in place shall not exceed 50% of the branch-circuit. In short, no one plug should exceed more than 80% of the circuit rating and that any stationary equipment (i.e. dishwashers, waste disposers) that constantly draws power should not exceed 50% of the rated circuit. Typical residential branch circuits (outlets, wall switches and fixtures) may be rated at 15 or 20 Amps.  Typically things like window air conditioners, washing machines and refrigerators are on their own circuit.

NOTE: This is a very basic description of this code requirement and how it is applied to typical residential branch circuits. There are numerous differences when applying the code to specific uses. Greater detail can be found in sections 210 and 220 of the NEC. 

 The National Electric Code (NEC) was originally developed in 1897. As the housing market continues to respond to new demands and changes in the industry, the Code is continually updated. However, as with most houses, the electrical system installed in the house was designed based on the code of the era and unless the house has had the electrical system upgraded, either all or part of the system is still based on the original design.  The most noticeable change to the average homeowner is that older homes have fewer outlets per room, and for this reason, it can be common to find excessive extension cords and power strips. All of these item place greater strain on a system that may have been designed and built 50 years ago. 

Why is the electrical outlet warm?

  1. What’s plugged in: Things  like  cell phone chargers, computer printers, lawn sprinkler controllers, DLS Modem, video cameras, MP3 players, cordless drills and some small appliance. All these products use a “transformer” (aka: wall wart). Based on what they do (change the voltage input to a different voltage output) will cause them to be warm. Unplug it, wait about an hour and check the outlet again. The outlet should be normal ambient temperature. It is not uncommon to find these wall warts as much as 20 degrees warmer than ambient. However if you find one that is too hot to touch, it should be replaced.
  2. Excessive Demand At An Outlet: As stated above, no one device plugged in to a single outlet (receptacle) should exceed 80% of the rated circuit.  To get perspective, residential grade appliances that are designed to plug directly into a standard (15A) wall plug will normally not exceed 1500W; such as a blow dryer (1500W/110V)/.95=14.35A  ((Watts/Voltage)/PowerFactor =Amps).  With two blow dryers in the same outlet or on the same circuit the circuit breaker should trip (e.g. turn off).  Add in the fact that in many older homes it is very common to find extension cords, outlet multipliers, outlet extenders or un-fused power strips. All of these items can increase the opportunity to overload an outlet.
  3. yellowstone-0111Excessive Demand on the Circuit: Most standard residential electrical circuits are wired in a series where the circuit wires loop through the electrical box, terminate on the outlet, then continue on to the next outlet.  In other words, the electrical current being used by one outlet (on the same circuit) may pass through terminations of another receptacle. If the current is excessive, the outlet may be warm without anything attached at the receptacle.  As part of an electrical design, it is normal  to have at least one outlet in the same room to be on a different circuit.  This allows you to share the load requirement from one room into multiple electrical circuits.  
  4. Poor Electrical Terminations: If electrical terminations (at the receptacle) are loose, or the wires are damaged, this too can cause excessive heat at both the point of use as well as in the circuit described in #2. Additionally, outlets terminated using the spring-loaded  stab-lock on the rear vs. the screw-down attachment can cause excessive heat.
  5. Oversized fuse or breaker:  Typically these values can be compromised in older homes as there are fewer outlets per room, and the circuits are not designed to support all the electronic gear we find in the modern home. Assuming the circuit was installed correctly, the circuit breaker should be the lowest rated item in the circuit and the wire in the wall should be the highest. For obvious reasons, if there was a fault or failure, you want the circuit breaker to fail first. If a breaker was replaced with a higher ampacity breaker, the circuit has been compromised potentially creating a fire risk by allowing higher current levels to pass through the circuit that was designed at a lower level. In this case finding a warm outlet is a warning that the wiring may be operating above its rating.
  6. Physical Deterioration of Plug: Outlet that appear worn, broken, cracked or chipped are all conditions that can compromise the function its function and can create heat at the outlet.

In urban areas, faulty wiring accounts for 33% of residential electrical fires.

What to Do?  Analyze the problem within your capabilities. Some of these suggestions may be beyond your comfort (experience) level, so you may want to contact an electrician at this point.

  1. Identify all the receptacles associated with the warm outlet.  After turning off the circuit breaker use an outlet tester to find all the outlets. Identify the circuit breaker rating found on the paddle of the switch. TIP: Inspect the entire house, both outlets and light fixtures. With the circuit breaker off you will be looking for dead outlets.
  2. Do any of the outlets have extension cords, power strips or outlet multipliers? Ensure the extension cord is rated  for its use.  Replace all unfused power strips or outlet multipliers with a fused power strip  as these devices include a circuit breaker to add further protection. Do not daisy chain multiple power strips or extension cords. Try to de load the outlet by re-associating the plugs to different circuits.
  3. Follow the testing methods as found in Electrical Switches and Outlets. These testing methods will identify any wiring issues that should be resolved as well.
  4. By now, you may have found the problems associated with an outlet, fixture or receptacle. If you still have problems, the outlets may be internally bad, the connections may have deteriorated or may be loose. With the electricity off, inspect the wiring of all suspect outlets. Check for tightness of the screw terminations, crimped or cut wires. You can also perform this test by using a digital thermometer gun with a laser site. Scan the electrical outlet, specifically the wiring terminations,  without disturbing the wiring. The probe should identify the problem by indicating a noticeably higher temperature.
  5. Replace suspect receptacles with higher quality equivalent receptacles using the screw down connection point.
  6. If you still have problems, review the tests found in the Electrical Service Panel post. Perform the tests that apply to the condition.
  7. If you still have problems, the circuit may have been compromised by enlarging the breaker, you may consider hiring an electrician to validate the condition and to correct the problem.

Additional Items to Consider

With over 15% of all electrical fires originating in the bedroom, municipalities have adopted local electrical code requirements that include arc fault circuit interruption (AFCI) circuit breakers to be installed in new construction. These breakers have the ability to recognize an arc usually due to a defective cord appliance or wiring.

One of the newest concern with electrical fires is the fact that many extension cords, plug adapters, power strips, appliances and etc. are coming from overseas areas that use counterfeit certifications. Here in the U.S., agencies such as UL, ETL, CSA are recognized as certified testers of electrical products. Unfortunately, many items are filtering in with fake labeling.  Always purchase name brand products from reputable stores and inspect the product for the safety agency’s certification.


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.


    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 – Mast

    January 6, 2009

    electrical-service-mastAt the house, the service cable will attach to a metal mast and enter a conduit through the weather-head. This conduit will serve a meter base. Inspect the mast and conduit to ensure it is mounted solidly, not pulled away from the house or overly distorted. A distorted mast is usually the result of undue stress on the service drop that may have occurred due to fallen tree limbs or debris that fell on the service cable. The masts are designed to endure quite a bit of stress and strain so it was probably a significant event to pull or bend the mast before the line was snapped (if at all).  This condition needs to be corrected as this could pinch or nick the conductors in the conduit. Additionally, this distorted mast can allow moisture or varmints into the house creating more issues. Consult a professional electrician regarding repair or replacement.

    Key Inspection Points

    1. Ensure Mast is secure and not pulled out of line.
    2. All roof attachments are secure and not causing leaks in the roof.
    3. Inspect for cracks or openings in the conduit that may be allowing water into the meter base.