transient voltage suppressors`

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shaw0486

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Location
baltimore
can someone tell me exactly what a transient voltage suppressors does and what the word transient mean. i know it functions like a surge protectors
 

gar

Senior Member
Location
Ann Arbor, Michigan
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090109-0916 EST

shaw0486:

From www.dictionary.com
tran?si?ent (trān'zē-ənt, -zhənt, -shənt) Pronunciation Key
adj.
Passing with time; transitory: "the transient beauty of youth" (Lydia M. Child).
Remaining in a place only a brief time: transient laborers.
Physics Decaying with time, especially as a simple exponential function of time.

n.
One that is transient, especially a hotel guest or boarder who stays for only a brief time.
Physics A transient phenomenon or property, especially a transient electric current.

A transient voltage as related to transient limiters usually means a large undesired voltage spike superimposed on your normal voltage. For example: A 120 V 60 Hz power line has a 8' Slimline connected to it. Upon opening the light switch a large inductive kick voltage is created that adds to the line voltage. This large voltage may destroy some electronic components.

If a non-linear device is placed across the 120 V line that draws no current below 200 V, but becomes a short circuit between the supply line and an internal 200 V level, then the supply line is clamped at 200 V, and you have a transient voltage limiter. This is an ideal device, none exists, but some come close under certain conditions.

The source of the transient voltage will have some internal impedance and available energy.

The transient limiter also has some internal impedance and capability to dissipate energy.

To provide reasonable clamping the transient source must have an impedance of moderate level relative to the limiter's impedance. Also the limiter must have an energy dissipation capability greater than the energy from the transient.

Most power line transient limiters have a very soft clamping characteristic and therefore do not sharply limit voltage. A 5000 V transient might be limited to only 1000 V with a 200 V limiter.

I do not know that a surge suppressor is any different than a transient voltage limiter. But the words surge suppressor could be applied to current if you wanted to. So could transient suppressor. Some ocean waves are transient and you might want to suppress these with some device. A 16" gun when fired produces a large mechanical transient in the ship and its position, and also a large transient sound boom and wind gust.

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dereckbc

Moderator
Staff member
Location
Plano, TX
There is not much difference between a TVSS and surge protector. A TVSS comes with more Bells & Whistles, but they do the exact same thing.
 

ohmhead

Senior Member
Location
ORLANDO FLA
M o v

M o v

Well we do agree there the same in a way , Transit meaning spikes or line voltage changes up do to switching or faults in system normal stuff .TVSS keeps line at its normal voltage or from a surge that may damage you electronic stuff . Inside these is metal oxide varistors there in every electronic device in most power supply circuits it is basically what a tvss is all about or most arrestors , M O V are rated at a certain voltage it will not let a voltage higher than its rated voltage to pass thur it it opens up becomes a high resistance to over voltage protecting your stuff . best to ya
 
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rattus

Senior Member
The "Sidactor":

The "Sidactor":

Another method is the "crowbar" circuit in which the device short circuits the line when the voltage threshold is exceeded. This causes a fuse to blow which protects the circuit from further damage. This technique is used in some telephone trunk lines for example.

"Sidactor" is the trade name of such a device made by Teccor/Littlefuse.
 
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