Transcript Power Quality

Power Quality
Understanding Effective Solutions
Presented by YOUR NAME HERE
What is power quality all about?
 First, it’s about understanding the needs of
the electronic system and it’s user
• What type of power disturbances affect the
system that’s being installed?
• How does the system react to power
disturbances?
• What happens to the user when a power
problem affects the system?
© 2001 POWERVAR, Inc.
What is power quality all about?
 It’s about not wasting resources
• Installing the correct power quality solution
• Not spending money unnecessarily
• Not loosing money during the warranty period
or after the system is on service contract
• Maintaining system uptime so that your
customer can accomplish what he hoped to
accomplish when he installed the system
© 2001 POWERVAR, Inc.
Where We Were
The Technology/Environment Matrix
High Tech Environment
Low Tech
Hardware
High Tech
Hardware
Low Tech Environment
© 2001 POWERVAR, Inc.
Where We Were
The Technology/Environment Matrix
High Tech Environment
Low Tech
Hardware
High Tech
Hardware
Low Tech Environment
© 2001 POWERVAR, Inc.
Where We Are
The Technology/Environment Matrix
High Tech Environment
Low Tech
Hardware
High Tech
Hardware
Low Tech Environment
© 2001 POWERVAR, Inc.
Where We Want To Be
The Technology/Environment Matrix
High Tech Environment
How do
we get
here?
Low Tech
Hardware
High Tech
Hardware
Low Tech Environment
© 2001 POWERVAR, Inc.
Getting Where We Want To Be
 We must understand what kind of electrical
power today’s systems want to see.
 First, we must understand how systems
have evolved.
 Today’s technology has different power
requirements than yesterday’s systems.
© 2001 POWERVAR, Inc.
Old Technology
Didn’t much care about
noise or neutral to ground
(common mode) voltage
 Needed stable voltage
 No voltage impulses
 Easily protected with our
“old friend” the dedicated
circuit.

© 2001 POWERVAR, Inc.
Dedicated Electrical Circuits
A Low Technology Environment
Main
Panel
Sub
Panel
© 2001 POWERVAR, Inc.
Dedicated Electrical Circuits
A Low Technology Environment
 Primary function was to prevent other
loads from affecting the nominal voltage of
the circuit powering the computer (sags
and swells)
 Secondary benefit was physical separation
of the computer from noise sources
 This was effective only because of the
relatively low state of the technology
© 2001 POWERVAR, Inc.
New Technology
Doesn’t much mind if voltage
varies over a wide range
 Needs power that is free of
transient impulses and noise
 Doesn’t like neutral to ground
(common mode voltage)
 May need continuous power
for servers, hosts, muxes, etc.

© 2001 POWERVAR, Inc.
What New Technology Sees
Main
Panel
Sub
Panel
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Protecting Modern Technology
 Dedicated Circuits
 Voltage Regulators
 Surge Diverters
 Noise Filters
 Uninterruptible Power Supplies
© 2001 POWERVAR, Inc.
Surge Diverters
© 2001 POWERVAR, Inc.
Surge Diverters
 Basic protection for catastrophic events
 Convert normal mode (damaging events)
into common mode (degrading and
disruptive events)
 Seldom effective for electrical
disturbances smaller than 300-350 volts
© 2001 POWERVAR, Inc.
Surge Diverters/Noise Filters
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Surge Diverter/Noise Filters
 Divert both high energy-high frequency and
low energy-high frequency power
disturbances away from the computer
 Convert normal mode to common mode
 Performance is very unpredictable -sometimes cause more problems than they
solve
© 2001 POWERVAR, Inc.
Even a UPS is no Guarantee
UPS
© 2001 POWERVAR, Inc.
UPS Systems
 Come in a variety of flavors (sine wave,
square wave, modified wave) WATCH OUT!
 Primarily a tool for providing backup power
 Can be a complete power quality tool if
properly selected. However, expect to pay a
premium price. Remember -- YOU GET WHAT
YOU PAY FOR!
© 2001 POWERVAR, Inc.
What is Really Needed?
 A device that combines surge diversion
and noise filtration with elements to
prevent the occurrence of neutral to
ground (common mode) voltage
 Such a device is called a low impedance
power conditioner or a low impedance,
power conditioned UPS
© 2001 POWERVAR, Inc.
The Power Conditioner
A properly designed power conditioner will allow less than
ten volts of a power disturbance to reach the system in
normal mode (hot to neutral) and less than 1/2 volt to appear
between neutral and ground (common mode).
© 2001 POWERVAR, Inc.
Voltage Let-Through is Important
 10 volt and 1/2 volt specifications
were
recommended by the semiconductor
industry as long ago as 1986
 Most surge protectors, filter devices, and
UPS products have let-through voltages of
330 volts or more in both modes
 These devices may prevent outright
destruction but can’t prevent degradation
or disruption
© 2001 POWERVAR, Inc.
Ask Yourself
 Off all our service calls,
– How often do we replace destroyed boards?
– How often do we replace malfunctioning boards
that have no apparent damage?
– How often do we respond to customer calls for
which there is no problem found
– How often does the customer report such things as
system lock-up, garbage files, and other system
operation problems?
© 2001 POWERVAR, Inc.
Three Points to Remember
 Non-destructive power disturbances are
far more common than destructive ones
 Non-destructive power disturbances cause
component wear and tear and system
disruption.
 Surge protectors, noise filters, and most
UPS systems do nothing but allow most
power disturbances to reach the computer
© 2001 POWERVAR, Inc.
Effective Protection
 A low impedance power conditioner that
contains an isolation transformer, surge
diverter, and noise filter or . . . . . . . . . .
 An uninterruptible power supply that
contains the same three protection
elements
 Either solution will provide total control of
the AC power interface with the computer
© 2001 POWERVAR, Inc.
By now you’re wanting to know . .
If this is
the answer to all
our problems,
why are we still
using dedicated
circuits?
© 2001 POWERVAR, Inc.
Why?
 Most systems now consist of one or more
networked components.
 The data cables that connect the different
components together can create “ground
loops” within the system.
 “Isolated grounding” conductors attempt to
minimize ground loops by keeping safety
ground impedance very low.
© 2001 POWERVAR, Inc.
Dedicated/Isolated Circuits
 In addition, most installers try to ensure
that all dedicated/isolated circuits for a
single system are fed from the same
transformer phase and the same panel.
 Ground loops must be prevented to ensure
that power disturbances do not enter the
data cabling subsystem.
© 2001 POWERVAR, Inc.
Otherwise this is what happens
Main
Panel
Sub
Panel
© 2001 POWERVAR, Inc.
Are there other alternatives?
 New patented technology combines power
conditioning with special elements to
prevent “ground loop” formation
 These special elements prevent power
disturbances and noise currents from
entering data cabling from the electrical
system grounding conductors
© 2001 POWERVAR, Inc.
Ground Guard
TM
Power and Ground Conditioner
Data Cable Ground
© 2001 POWERVAR, Inc.
Ground Guard Conditioners
 Provide all the functions of normal low
impedance power conditioners -- surge
diversion, noise filter, and isolation
transformer
 Prevent ground currents and power
disturbances from entering the data
cabling subsystem
 Prevent formation of ground loops
© 2001 POWERVAR, Inc.
Ground Guard Conditioners
 Eliminate the need for dedicated/isolated
electrical circuits
 Eliminate the requirement for same
transformer, same phase wiring
techniques
 Eliminate the hassle, time, and expense
associated with special wiring
© 2001 POWERVAR, Inc.
What About UPSs
 UPS products should still be used to
provide reserve power for servers, muxes,
hubs, etc.
 UPS systems should be sine wave and
either contain power conditioning
elements or be installed with a power
conditioner attached
© 2001 POWERVAR, Inc.
What about existing installations?
 Power conditioners can be added to
existing installations and UPS systems
© 2001 POWERVAR, Inc.
Where We’ve Arrived
The Technology/Environment Matrix
High Tech Environment
Low Tech
Hardware
High Tech
Hardware
Low Tech Environment
© 2001 POWERVAR, Inc.
Effective Power Quality Solutions
 Reduce service costs by eliminating no
problem found service calls, failed boards,
and destroyed systems
 Make happier customers and more
productive field engineers
 Increase revenue and expedite
installations by eliminating electrical
contractors
© 2001 POWERVAR, Inc.
Effective Power Quality Solutions
Ensure that today’s high
technology systems are installed
in a high technology electrical
environment.
© 2001 POWERVAR, Inc.
© 2001 POWERVAR, Inc.