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Power Quality

Halton Hills Hydro is committed to providing distribution excellence in a safe and reliable manner. We are committed to providing the best possible quality of power and least amount of power interruptions and disturbances we can provide.

In this ever growing and changing world in which we live and work, customers (residential, commercial, and industrial) rely on the utility to provide uninterrupted power that is free of disturbances that can affect their equipment. We realize that even small disturbances that may not impact some customers could affect other customers with more sensitive equipment such as industrial processes and we are here to help.

Types of Electrical Disturbances

  • Voltage Sag: Characterized by a reduction in power on the distribution system. Typically a sag event results in voltage levels falling below acceptable limits.
  • Voltage Swell: Characterized by an increase in power on the distribution system. Typically a swell event results in voltage levels rising above acceptable limits.
  • Transients: There are two types of transients, impulsive and oscillatory. Impulsive transients are characterized as a quick high magnitude change in voltage/ current. An oscillatory transient is characterized by a change in the condition of the voltage and/ or current waveforms.
  • Interruptions: An interruption is a loss of power where no voltage or current is present.
  • Waveform Distortion: Numerous types of distortions can affect the supply voltage (ex. harmonics, noise, ringing)Harmonics are often a result of non-linear loads such as solid state electronic equipment turning on/ off, variable speed motor drives, ballast lighting, etc and can occur when single phase loads are added to one phase of a three-phase system but may also be present in wholly single phase systems.

What Causes a Power Disturbance (Internal/ External)?

In your office or at home, there are all sorts of equipment that can negatively affect your power supply. There are numerous possibilities as to where and how electrical disturbances are being created. A few examples are provided below: If you are operating an industrial process you may think that problems you are experiencing are a result of a large machine not operating properly, but if fact it could be the office computer or printer introducing disturbances and affecting your machinery.

  • In your manufacturing plant where you have your own service monitoring equipment, you find the voltage dips below acceptable levels when you are starting up equipment. This might be the result of starting a motor and it drawing a large amount of current (referred to as in-rush current) when starting. This in-rush of current required by the motor can cause the voltage level to sag until the current being drawn by the motor decreases to its operating current (ie: steady-state current).
  • You are at home and you notice that every time you turn your hair dryer or vacuum on the lights dim. That may mean your equipment and the lights are connected in a series circuit and starting some equipment like a vacuum could cause the voltage to sag momentarily which can be visibly seen by lights dimming and then returning to normal brightness.
  • You are in a building and notice some rooms and lights have power but others do not. At other times the rooms that did not have power now have power and others do not. This may be the result of a loose connection either at an electrical panel or other point in the building. Loose connections, poor grounding, and incorrect wire sizes can result in poor power performance.

In all cases, a licensed electrician and/ or manufacturers of equipment may be able to assist you in examining the problems you are experiencing within you facility. By no means should you ever consider opening and working on a live electrical panel, socket, machine or other piece of equipment for which you are not qualified.

There is a wide variety of equipment you could be operating that can affect your service. Examples of such equipment are:

  • Computers/ printers/ Uninterruptable Power Supply (UPS)/ electronic equipment/ kitchen equipment
  • Lighting
  • Air conditioners
  • Compressors and welders
  • Motors and Frequency Drives
  • Load switching devices
  • Improperly balanced circuits (internally)

However, your internal operations may not be the sole source of the problems you are experiencing. The electrical distribution system we and all other utilities operate is subject to a variety of influential disturbances that can cause disturbances in the power being supplied to you. Some of the more common influences are:

  • Weather (lightning, wind, ice)
  • Tree branches or animals contacting our power lines or equipment
  • Vehicular accidents
  • Digging into underground cable/ contacting overhead wires
  • Equipment malfunctions
  • Theft and vandalism
  • Capacitor bank switching

The extent to which a disturbance affects your residence or facility can in part be dependent upon the magnitude of the event and its proximity to you.

We always work to prevent problems on our distribution system from impacting your service by installing protective equipment, performing preventative maintenance and inspecting our equipment on a regular basis. However, there are some events (ex. weather related) which we have little to no control over but we do our best to restore power as soon as possible in a safe and professional manner.

Disturbances to Your Service

What is a disturbance or how can one be identified? Well, consider the following questions:

  • Do your lights flicker/ dim/ or brighten?
  • Does your computer or other electronic equipment turn off on its own?
  • Is your process equipment acting abnormally?

If so, this may be the effects of power disturbances. Disturbances, even momentary ones, can affect sensitive equipment.

In today’s technological world, power disturbances are more prevalent than ever but remain undesirable. It is always a good idea to ensure you are protecting your equipment at home and at work. Protection of your equipment ensures that it will function properly and not cause you or your business problems.

You may ask why in today’s modern age of technology have power disturbances become more of a problem. Prior to the use of computers, printers, and digital control equipment, much of the equipment used in the workplace was of a linear nature and did not introduce transients into the distribution system. However in today’s more technologically advanced society where computers, printers, and digital control equipment are much more prevalent, these non-linear loads can introduce transients into the electricity supply and affect equipment.

How can Halton Hills Hydro Help?

Halton Hills Hydro can help by monitoring your service for power quality problems and assist in identifying sources of disturbances. We have specialized equipment capable monitoring the quality of power and will work with you to determine where the source of disturbances may be originating. We typically install power quality monitoring equipment at the point of demarcation or as close as physically and safely possible. Contact our Engineering Department at 519-853-3700 to address and discuss your concerns. You can also submit a request using our Power Quality Report Form.

Power Quality Report Form

If the sources of power disturbances are being generated within your facility we will advise you to contact a licensed electrician. Electricians are often best suited to work with you to examine your internal electrical set-up and make recommendations.

Where the source of power disturbances are found to be on the utility power distribution system, we will take action as best we can to correct the problems on our distribution system.

In the design of your internal electrical set-up, it is always a good idea to work with qualified professionals to determine what effects your electrical equipment will have on your facility. The design stage is the best time for you to decide on and install protective devices to protect your equipment and help yourself ensure your facility remains in operation. As well, regular backup of data, installation of correctly sized UPS’s, and making sure sensitive equipment is protected are a few of many ways you can better ensure you are protecting yourself against power disturbances. Your equipment manufacturers, suppliers, and installers may be able to assist you in determining protective needs for equipment and should be consulted in this respect.

Please see Halton Hills Hydro’s Conditions of Service for additional information.

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This information is provided as a public service. While every effort was made to provide accurate information, Halton Hills Hydro does not guarantee results nor do we assume liability for any loss, costs, damages or injury whatsoever, resulting from the use of this material. Halton Hills Hydro Inc. shall not be held liable for any misinformation or action taken by a customer or those they contract as a result from reading this information.

Download Power Quality Report Form (PDF)