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(Surge
Protector Questions?)
HOW OUR SURGE PROTECTORS WORK
Most surge
protector manufacturers make grand claims about their products but
publish little of the technology involved.
We claim that our Brick Wall surge
protectors offer performance, reliability and safety advantages that
cannot be matched by other surge protectors. The following
represent the basic engineering principles.
External surges first encounter the
Series Mode surge reactor L1, and must pass through this surge reactor to
reach the protected equipment. L1 resists the surge frequencies and
immediately (zero response time) provides current limiting. The
Brick Wall surge protector reactor behaves like a relatively high value resistor at the
surge frequencies and dissipates some of the surge as heat. Unlike MOV’s, TRANS-ZORBS and similar shunt
based surge protectors that use elements weighing less than
1/4 ounce, Brick Wall surge protectors can easily absorb any surge
repeatedly with absolutely no degradation.
Our surge protector reactor in conjunction with
the capacitor C2, restricts the incoming voltage slew rate of
up to 5,000 volts per microsecond to a maximum of 100 volts per
microsecond (1 volt per 10ns). L1 and C2 operate continuously and
react instantly for surges or noise lying within the normal dynamic
range of the power wave. If the surge exceeds the normal ±180 volt
peak dynamic range of the power wave, the dynamic clamp
circuit (D1 C3) which tracks the peak of the power wave comes
into play. With a diode clamp response time of 5ns, and maximum slew
rate limited by L1 and C2 to 1 volt per 10ns, even a worst case
surge will be clamped by the time the voltage exceeds the clamp
voltage by 1 volt. The clamp circuit places a 180µf capacitor (C3)
in parallel with C2, reducing the surge slew rate to about 8 volts
per microsecond.
Two 'crowbar' circuits act on high
energy surges. The series connected crowbar circuits consist of a
SCR switch, inductor and a 180µf capacitor, chosen to minimize
the disturbance on the power wave. The first crowbar circuit
responds to the slew rate of the incoming surge. If a surge is
large enough to generate more than 30 volts in less then 2µs across
C3, then the slew rate crowbar neutralizes the surge. Should C4
become charged, and the voltage again begins to rise, a second
crowbar will activate at 220 volts peak to provide a final measure
of protection.
Since the surge reactor is a high
impedance at the high frequencies of the surge, minimal high
frequency current flows in the neutral wire and consequently the
'common mode' problem created by simple shunt surge protectors does not
exist with Brick Wall Surge Protectors.
Our engineering staff is always
available to answer any technical questions you may have. Computer
simulations and custom configurations can be provided.
HOW OUR SURGE PROTECTORS WORK
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