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             Philip C. Waters Electrician

                 PO Box 890

                 Pocasset, MA 02559-0890

                 (508) 564-6188  | 508-524-5562



Serving Cape Cod and Southeastern Massachusetts

  MA Lic # A19901, MA Lic # 30252 E, CT Lic # ELE 0125681






 Voltage drop is a well-known industry wide problem that has long been overlooked


Having worked continuously for 40 years in the electrical field, I have confirmed several of my suspicions relating to the issue of voltage drop. Starting out my career as an apprentice electrician wiring houses, I went on to receive an Associates in Science Degree in Electrical Technology and hold Master Electrician licenses from Massachusetts and Connecticut. Having completed advanced level courses in math and physics has given me the analytical skills needed to trouble shoot and solve more complex electrical problems. I have also taught journeymen electrical code and theory classes and hold a Preliminary Educator License. Having prior experience as an interim wiring inspector and listening to complaints from customers, I found that there were several major safety concerns dealing with too much voltage drop. I feel that there needs to be a better solution to fix this problem.


I have discussed the problems concerning too much impedance that can cause voltage drop with a lead application engineer who works for a major US instrument manufacturer. The engineer sent me a multifunction tester from the UK which I now use to evaluate home circuits. The instrument performs a loop impedance test from an outlet to the secondary side of the utility transformer and returns to the initial outlet to complete the loop. Too much voltage drop will indicate excessive impedance in the circuit which is extremely inefficient due to the high cost of electricity and the amount of wasted energy that converts to heat loss. It can cause power quality problems, equipment failure, the flickering of lights, and motors to burn out. Left unchecked, it can be quite costly in property damage to the US consumer.

Plug-in technology now provides a new tool to evaluate voltage drop conditions with excellent results. AC load testers are slowly becoming popular in the US and they can reveal a great deal more information. You can now easily check the loaded voltage drop at any point in home circuits. Instantly, scrolling through the instrument’s windows you can view the percentage of voltage drop, hot impedance, neutral impedance, ground impedance as well as check the amount of available short circuit current needed to safely trip a circuit breaker. These are all critical pieces of information needed to check the integrity of branch circuits.

Now available, this technology allows for safe circuit analysis, provides greater advantage to diagnose a problem much faster, displays GFCI trip time and trip current limits to check devices are operating within manufacturer specifications. The reliability and performance of electronic devices including GFCI outlets and arc-fault circuit breakers have taken on a greater role in electrical safety. They are extremely important measures used to prevent electrocution and help to prevent arcing that can lead to fires. These electronic devices are much more sensitive to voltage drop. When home wiring is completed, limited functional checks of the branch circuit wiring is generally performed. This reveals limited information about the circuits ability to function correctly. The use of more modern electronic diagnostic tools provides greater capability to evaluate performance and to check unsafe circuit conditions demonstrating a clearer picture of the overall circuit condition. Therefore, as a result, vocational training methods will have to change to address the latest technology needs.


 Voltage drop problems appearing on Cape Cod

The main issue appears to be the distance from the supply transformers in the public way to a home’s point of attachment. This creates a greater share of the voltage drop further down the line on the consumer side of the demarcation.  Beginning at the secondary side of the utility supply transformer cascading ends at the furthest outlet in the home. For reasonable efficiency, a maximum limit of five percent is recommended by the National Electrical Code. Most homes throughout the region far exceed this limit.

It appears in part to be a two-tiered problem that has not been fully addressed.  The utility side of the demarcation is the power company regulated by the Department of Public Utilities, and on the consumer side of demarcation is the home owner regulated by the authority having jurisdiction who enforces the Massachusetts and National Electrical Code for compliance.

On the consumer side of the demarcation, internal wiring issues can also contribute to additional impedance that can cause voltage drop. The problem can be exacerbated by the unprofessional wiring activities that can be difficult to enforce. In many cases, the wiring is unsafe, non-code compliant and puts occupants at risk. In larger scale homes, this presents an even greater challenge as the wires would be run at a greater distance. There are many contributing factors such as the unlimited number of electrical outlets on a circuit and loose wiring which can create potential fire hazards.

In the United States, a lower 120/240-volt, split phase system is typically used for residential customers. It is a multiple source voltage system that provides dual voltages. 120-volt circuits for general lighting and small appliance loads or it can be configured to serve heavier 240 volt loads such as electric dryers, ranges, heating, air conditioning and other 240v loads. However, 120 volts to ground, when used to supply 120-volt residential loads, cannot travel a very far distance over a wire. The voltage system in the US is unlikely to ever change compared to other countries but can be made much more efficient and safer.


Aging overhead electrical infrastructure

Repeatedly in the Northeast, and throughout the US there are problems with an aging electrical infrastructure that has been heavily impacted by: multiple storms dating back as early as the Hurricane of 1938; old utility poles and transformers that line the public way; overhead utility wiring that requires constant maintenance and repair; damage caused by falling tree limbs during storms; and power outages resulting in downed poles from traffic accidents. The public is then dependent on the utility company’s timely response to restore power when necessary by bringing in crews from outside the area to make emergency repairs. Having to continuously repeat this process eventually the cost is passed on to the American tax payer.


Fixing high impedance and arc-fault breaker problems

Other contributing factors to cause voltage drop are homes wired during the 1970s and ‘80s that used stab-in receptacle outlets. This wiring method was later discovered that the wires at the back of the outlets loosened over time due to possible vibration. This caused high impedance connections that resulted in the overheating and the eventual melting of these wires.

In 1999, arc-fault circuit breakers were originally developed to help prevent against arcing conditions. They were initially required by the National Electrical Code for bedrooms to prevent fires and perform other functions including overload, short circuit, and ground fault protection. In recent years, additional code regulations which requires more arc-fault breakers has fielded questions regarding the necessity and cost. There have been many concerns raised with arc-fault circuit breakers nuisance tripping. Manufactures appear to be trying to find a solution to rectify this issue. Nationwide, it is costing businesses revenue due to repeated call backs by frustrated home owners looking for answers.


Arc-fault circuit breakers are electronic devices that are sensitive to excessive voltage drop. With the increasing number of home electronics, which include appliances, the compatibility with these breakers has raised questions as the appliances are also sensitive to this power quality.  This presents nuisance tripping issues for the consumers. Unfortunately, the current infrastructure is not keeping pace with the modern technology.


Currently inspections are carried out by the electrical inspectors for code compliance and are mostly visual observations. Now, the voltage drop limit is not enforceable by the code. Therefore, the electrician installer is not required to check the installation in new or existing dwellings for excessive impedance that causes voltage drop. It has been my experience that this is becoming, with more occurrences, a major problem in housing across the region. Unsafe circuit problems in residential and senior housing is critical to fire prevention.


In other countries, much of the electrical systems are buried underground, and they have been using electronic diagnostic technology to their advantage. The most significant difference is the electrical contractor is required to verify that the electrical installation meets strict impedance values. The electrical contractor then submits documentation to the utility company before any final connections are made. This requirement assures the homeowner and general contractor that the electrical installation meets their national safety standards. 230/400-volt systems used in other countries are potentially more dangerous but are made much safer due to stricter safety verification standards. This type of supply voltage is used for homes by other counties around the world. There are several advantages of having 230 volts to ground system. As an example, the voltage can travel over a wire a much greater distance.


Renewable energy demand

There is now a greater demand for the use of renewable energy by using wind and solar power systems to lower our energy cost. Governments from around the world are concerned with the amount of CO2 emissions that can cause climate change. New polices shared by countries around the globe are trying to lower the amount of greenhouse gases that can damage the ozone. Utilities companies are now required to buy back power generated from renewable energy sources. These measures are helping to

lower our dependency on oil by reducing the amount of fossil burning fuels saving the environment for future generations. The demand for solar installations has increased significantly. Solar power systems employ electronic inverters and photovoltaic arrays adding to the greater demands of improving the efficiency of the electrical grid system.


Power Company Rate Hikes

Utility companies across the country have now been deregulated requiring customers to make a choice to buy power from a large pool of suppliers. Now the utility company in Massachusetts wants to charge some customers a huge rate increase if they don’t shop for competitive power. The public should not accept this $290 million proposal until the US government, the National Fire Protection Association, National Electrical Code, Department of Public Utilities, and the utility companies lay out a plan to change the regulations and upgrade the electrical infrastructure to address voltage drop problems.

In addition, utility companies in Massachusetts also charge customers costly design fees for upgrades to accommodate additional consumer loads. After the point of attachment, the responsibly shifts to the property owner to maintain and to pay for equipment repair such as private poles and service entrance cables.


The issue is not just an individual customer problem or complaint but appears to be national infrastructure problem with the electrical grid.


Problems with excessive voltage drop can be reported to the Department of Public Utilities who will investigate an individual customer’s complaint to determine the cause. Voltage drop awareness will likely bring present and future electrical code rules into questions. A coordinated effort to improve electrical safety will be needed. This will likely require government resources to provide funding to upgrade the electrical infrastructure on both sides of the demarcation boundary. Utility companies have done much work to repair and replace transformers and poles but much more work is needed. Billions of dollars in new investments will have to be made to fix this problem for our future needs.


NAPCEP Photo Voltiac Associate PVA-093016-015616

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