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Mid-April 2006
American Power Conversion (APC)
The Virtues Of Good Power Protection And Conditioning
How can your system benefit and what type of power protection solution is best for you?
Article By Patrick Donovan, Senior Product Manager at APC
Power Is The Foundation Of Your System
Every type of system on earth relies on a safe and secure foundation for its
very survival. Democracies rely on the rule of law, corporations on its
employees, buildings on their concrete foundations and transportation systems
rely on the roads, tracks and waterways for their continued operation. In
a very similar way as these examples, audio-video systems depend on a secure
foundation of power. Without safe and steady power, an AV system’s
performance and even its very survival are at risk.
Threat Assessment
Dangerous power disturbances can occur anywhere, anytime. For most
people in North America, their utility power is safe and relatively steady most
of the time. For many others, however, poor power is an everyday fact of
life. Either way, it only takes one bad power event to harm equipment.
There are many factors that impact the probability of experiencing a power
problem that leads to reduced performance or outright damage. Some of
these factors include weather, wiring conditions in your house, state of loads
on the Utility Company, quality of power distribution of the Utility’s
network, animal infestation and even the existence and status of other
electronic equipment in your own house. Following is a list of some of the
common power disturbances that can occur in your home along with what impact
they can have on your audio-video system.
Surges
This is a short-term increase in the voltage level often caused by the
starting and stopping of household appliances such as heating furnaces, air
conditioning units, power tools and washing machines. Surges can also be
caused by the Utility itself or by other large loads connected to the
Utility’s power network. Depending on the amplitude, these power surges
can put a lot of electrical stress on the power supplies in your home
audio-video components. This stress can shorten the lifespan of the
equipment or even lead to immediate failure.
Spikes
A power spike constitutes a very dramatic and near instantaneous increase in
voltage that like an electrical tidal wave can destroy most anything in its
path. Lightning is a common cause of this. If unprotected, a nearby
lightning strike can destroy your entire system in a single flash.
Electrical Noise Interference
If severe enough, Electro-Magnetic and Radio Frequency Interference (EMI/RFI)
can travel through the air or over electrical wiring to negatively affect
audio-video signals that lead to less than ideal picture and sound quality.
This interference can be generated by home appliances, motors, nearby radio
stations and even AV components themselves. It can also cause sensitive
equipment like media servers, Digital Video Recorders (DVRs), automation
controllers to behave erratically, lockup, or even crash.
Brownouts/Over-Voltages
Short to longer-term low (brownout) or high (over-voltage) voltage levels can
be a very common, everyday experience for many people. In fact, brownouts
constitute the most commonly experienced power anomaly. This problem is
often noticed when you see your lights flicker momentarily or dim slightly for a
second or two. These fluctuating voltage levels are often caused by the
Utility Company as they work to manage shifting power demand throughout the grid
during peak activity. Larger loads in the house (like when a furnace turns
on) can also cause voltage fluctuations. If severe enough, these low and
high voltage levels can hurt AV quality while also putting a lot of stress on
the component power supplies. Just like a surge, these types of power anomalies
can shorten the life span of AV equipment.
Blackouts
Outages can be caused by many things including overloaded Utility networks,
downed power lines, animal infestation and weather. Depending on what type
of AV system you have, the effects of a blackout can vary significantly.
At a minimum, your entertainment is interrupted for the duration of the outage.
For those with a DVR, scheduled recordings can be missed and recordings stored
on the hard drive can be lost permanently. If power is lost at just the
wrong time, the hard drive can even be rendered useless. Cutting power
suddenly to a projector, plasma or other light bulb-based TV before the internal
fans have a chance to cool down these expensive bulbs can lead to premature
failure of the video display. Many components also contain system pre-sets
that can be lost due to a power outage.
Ground Loops
Just about every AV system involves having multiple components connected to
each other via AV interconnect cables. These components are often plugged
into several different power receptacles. This means that the system can
have several different grounding points. Between any two ground points
there is likely to be a potential difference in charge (ie, voltage).
Because two components are connected to each other via some sort of
interconnect, this voltage will try to equalize between the two grounds by
having current flow through one component over an interconnect cable to the
other component connected to the other ground point. This current flow
often results in an audible hum heard through the speakers or seen as bars on
video displays. If the current traveling over the cabling is large enough,
hardware damage can even result. Many AV power protection units allow you
to connect all your components to a single ground point, thereby eliminating the
annoying and potentially dangerous ground loop.
It’s Not A Question Of "If", But Rather
"When"...
It should now be clear that your system faces several different power-related
threats from several different sources, most of which you have no control over.
You do, however, have the power to mitigate all these threats by selecting an
appropriate power protection solution that will protect your investment,
possibly improve performance and maintain uninterrupted operation.
Promises Of Better Picture And Sound...
When selecting a power protection/conditioning unit, beware of companies that
make wild claims of improving sound and video quality. If you have power
problems that are severe enough to negatively impact AV quality, then a good
power conditioner can make a positive difference by eliminating or at least
reducing the cause of the signal degradation. Another way to phrase it is
that a good power protection unit enables your system to perform to its maximum
capabilities by eliminating or reducing power problems that impact AV signal
quality. Without these power anomalies, a power conditioner will not
magically make things better. On the other hand, a poorly designed device
can, in fact, degrade quality by injecting more noise into the system or by
reducing signal strength of AV signals traveling over satellite, antennae or
COAX lines. Some inappropriate conditioners can even cause dangerous
situations, especially those lacking a UL, CSA or other regulatory listing.
What Type Of Power Protection Unit Or Conditioner
Is Right For Me?
The answer will depend on which power protection benefits are important to
you. If you’re principal concern is protection of your investment from
damaging surges, spikes and lightning, then a good surge protector may be all
that you need. However, if you also want to ensure power does not impact
your entertainment experience by degrading signal quality in addition to
protecting the hardware from damage, then you should select a complete power
conditioner that offers surge protection, noise filtering and voltage
regulation. Beware of companies who market their surge protectors as
“power conditioners.” Remember, a complete conditioner offers surge
protection, noise filtering and voltage regulation. If your system
includes a DVR, projector, plasma TV, LCD TV, home automation equipment and/or
components with volatile memory settings, then a battery backup system is your
best choice. Battery backups that are specifically designed for use with
high performance AV systems will likely also include a high degree of surge
protection, noise filtering and voltage regulation. Be sure to check for
these important features before purchasing one. A power conditioning
battery backup represents the most comprehensive solution in that it protects
you from virtually every type of power anomaly found in a home environment.
Which ever type of solution you choose, make sure there are enough outlets to protect all your connected components. Leaving one connected component unprotected creates a power path to all the other components via the interconnect cables. Also, ensure that the unit has the appropriate number and type of COAX, phone and/or Ethernet surge protection jacks. It is not uncommon for surges and spikes to travel over these data lines. Higher end AV power protection units will include COAX, phone and/or Ethernet jacks that will protect your system from these types of surges, and do so without significantly impacting signal strength. It is also good to choose a solution from a reputable company who has a proven history of standing behind their products. Look for products that offer lifetime equipment protection policies that will pay to repair or replace any of your costly equipment should it be damaged by a power event while connected to the protection unit.
"I Can Just Go To My Local Computer Retailer And Pick One Of These Things Up, Right?"
This is not a good idea. There are several reasons not to use a PC power protection unit for your home AV system. It is important to select one that has been designed for audio-video environments. PC or home computer surge protectors and battery backups have almost no noise filtering. Additionally, battery backups designed for your computer are usually not capable of supporting the large current draws seen with bigger AV components. If these components turn on while the battery backup is operating on battery power, for example, its possible to permanently damage the backup unit.
Aside from the performance reasons mentioned above, there are other unique features found with better AV power protection units that make them more suitable for your AV environment. The industrial design is usually such that it lends itself to being placed within an AV rack or amongst living room decorum. The shape is similar to other AV components with easy to decipher digital displays on the front panel and outlets on the rear. High-end AV power protection units allow you to adjust display and LED indicator brightness. Superior AV battery backups are specially designed to remain cool while contained in a rack and will also operate much more quietly than a unit designed for computers. AV power protection units will also tend to offer you more data line surge protection jacks that are more prevalent in audio-video applications.
In Summary...
Regardless of how good your power quality might have been in the past, your
entertainment system does face many different power threats that could at any
time strike and damage your equipment or reduce its performance. A good
power protection solution represents inexpensive and hassle-free insurance.
You’ll have peace of mind that your investment is safe and secure. Your
system will continue operating at its peak capabilities regardless of what
happens to the power.
Company Information
American Power Conversion Corporation (APC)
132 Fairgrounds Road
W. Kingston, RI 02892
Voice: (800) 555-2725
Website: www.apc.com
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