Here is where we'll try to answer some often
asked questions. If you can't find your answer here, please feel free to call
and ask in person and we'll do our best to help.
-
What causes
my semiconductors and power supplies to fail?
-
My electronic equipment is going to be in a country where
ac is known to be unreliable, and equipment failures are commonplace. What
can I do to protect my equipment from experiencing failure and at the same
time make it run as smooth as possible?
-
I
have been told that a low-impedance isolation transformer will make my
systems work better. What exactly are the benefits of transformer
isolation?
-
What
are sags, source impedance, and neutral-ground bonds? And while you're at
it, how do I figure out what size UPS to buy?
- What
is PWM AVR?
-
What is a modified sine-wave
UPS?
-
I'm
wanting to get a couple of UPS to ship along with a small computer
network and telecommunications system to an underdeveloped country. What
kind of UPS should I get?
-
Why should I choose a line conditioner with an E-I type core transformer
instead of a toroidal isolation transformer for my medical applications
requiring a UL 2601 medical isolation transformer?
-
When printing out the home page or product group pages, not the PDF pages,
the right edge of the page is cut off and some text is missing. How do I fix
this?
1.
What causes
my semiconductors and power supplies to fail?
Thunderstorms and lightning are the most dramatic and
destructive causes of power line problems. However, downed
utility poles, squirrels, birds, and snakes shorting out
transformers, or even large industrial motors switching on
and off can create power surges. These surges are literally
surges of overexcited electrons, which contain a lot of
energy in short duration bursts.
Why
Power Supplies and Semiconductors Fail
~
(Click here for the paper in Adobe Acrobat PDF format)
2.
My
electronic equipment is going to be in a country where ac is known to be
unreliable, and equipment failures are commonplace. What can I do to
protect my equipment from experiencing failure and at the same time make
it all run as smooth as possible?
There is no easy short answer to this.
Voltage instability is more and more becoming a problem as population
demands grow upon what often is a weak ac generation system to begin
with. There are solutions that work though. There are two papers that
focus on this, the first having more to do with voltage regulation and
coordination of power quality devices, and the second with four different
types of uninterruptible power systems for where uninterruptible power
is also an issue.
Protection
Of Telecom Sites In Countries With Unstable AC Mains
~
(Click
here for the paper in Adobe Acrobat PDF format)
Choosing
UPS
Protection For Underdeveloped Countries
~ (Click
here for the paper in Adobe PDF Format)
3.
I have been told that a low-impedance isolation transformer will make my
systems work better. What exactly are the benefits of having
one?
The benefits of adding a low-impedance
isolation transformer are many. Logic accuracy is enhanced, electrical
noise on the vital ground line is virtually eliminated, and other
benefits are further documented in a short but concise paper that
addresses this question.
The
Benefits of UPS and Line Conditioners with an Isolation Transformer
~
(Click here for the paper in Adobe Acrobat PDF format)
4.
What are sags, source impedance, and neutral-ground bonds? And while
you're at it, how do I figure out what size UPS to buy?
These are terms that
help us define the electrical environment our systems work in. They
are important to understand. Below is a white paper which addresses
them in a brief but clear fashion.
TSi Power
Primer and Guide to UPS Terms
~
(Click here for the paper in Adobe Acrobat PDF format)
5.
What
is PWM AVR?
PWM AVR stands for
Pulse-Width-Modulated Automatic Voltage Regulation. This is the
latest state-of-the-art technology for automatically regulating your
incoming voltage levels. It utilizes an IGBT based inverter topology
to electronically modify the incoming electrical waveform to an
ultra-pure sinewave with ideal voltage and power quality
characteristics.
6.
What is
a modified sine wave UPS?
Typically this is what is called a
"standby" UPS. In normal operation it delivers utility
generated sine wave power. During an outage, or severe voltage drop,
the UPS takes over with battery backup and an output of an inverter
created modified sine wave. The
pulse-width-modified and optimized peak-voltage modified
square waveform can actually be more beneficial for some switchmode
power supplies. Switchmode power supplies are what
predominantly are utilized by computer and telecommunication systems.
The
Merits of Standby UPS with Modified Sinewave Output
~
(Click here for the paper in Adobe Acrobat PDF format)
7.
I'm
wanting to get a couple of UPS to ship along with a small
computer network and telecommunications system to an underdeveloped
country. What kind of UPS should I get?
That will depend upon what your
situation requires. You have to make a value judgment as to the
criticality to the mission that the equipment has. There are different
topologies of UPS. The following paper details the most cost-effective
ones and their suitability to handle an underdeveloped country's
electrical infrastructure.
Choosing
UPS
Protection for Underdeveloped Countries
~ (Click
here for the paper in Adobe PDF Format)
8.
Why should I choose a line conditioner with an E-I type core transformer
instead of a toroidal isolation transformer for my medical applications
requiring a UL 2601 medical isolation transformer?
TSi Power's medical-grade ILc-Med
isolation line conditioners were developed to meet the very low leakage
current requirements of UL 2601 standards for safety applicable to
medical equipment power supplies. TSi Power has deliberately chosen an
E-I core isolation transformer as the key component that provides
electrical isolation between input and output ac for the reasons stated
below:
1. An E-I core transformer is more stable and predictable for both
static and dynamic ac line and load conditions than an equally sized toroidal
transformer. A toroid's very low primary winding resistance acts as a short circuit during the
first half cycle of ac - which can trip an upstream circuit breaker. This problem
becomes especially serious for larger toroidal transformers of 500VA or larger whereas
even the largest of E-I core transformers do not exhibit this type of problem, thanks to
its greater reluctance against half-cycle pulses, which significantly softens the
impact of the first half cycle pulses.
The half cycle pulse
is a rather frequent occurrence during thunderstorms when spark- gap type surge arrestors operate to protect power lines and
distribution transformers. Grid switching and on/off cycling of power can also result in
unwanted tripping of circuit breakers.
2. TSi Power's E-I core isolation
transformers can easily be made to work with all common frequencies of 50Hz, 60Hz or between 47-63Hz. In
comparison, designing a toroidal isolation transformer for 50Hz (especially if the
power line is also unstable) can be a major challenge and an expensive exercise.
3. An E-I core transformer is an
inherently superior noise filter than a toroidal transformer. TSi Power's E-I core isolation transformer line conditioner
also includes a 3-stage surge protection and noise filtering system to provide the best
surge protection and noise filtering as recommended for the typically very expensive and
mission-critical systems whose down-time can be very costly and/or life threatening.
In summary, a toroidal transformer can be
used in low power (less than 500VA) applications as a medical-grade
isolation power source if one is willing to accept a reduced performance
in noise filtering and surge protection. However, if the load exceeds
500VA and excellent noise filtering and power protection are also
required, then only an
E-I core transformer-based isolation line conditioner should be used for
enhanced reliability, stability, noise filtering and protection of
connected equipment.
9.
When in Internet Explorer, and
printing out the home page or product group pages, not the PDF
pages, the right edge of the page is cut off and some text is missing.
How do I fix this?
While you are in Internet Explorer,
look up in the upper left corner, and click on:
File, then Page Setup and you should see
a dialog box similar to below.
Set your left and right margins to 0.5
inches, or the settings below, and that
should fix the problem. If it doesn't, you'll have to contact your
printer manufacturer for other help.
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