How do surges damage electronic equipment?

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Lightning – Globally there are 1.4 billion lightning strikes occurring per year as recorded by the Lightning Imaging Sensor aboard NASA’s Tropical Rainfall Measuring Satellite. This high-frequency occurrence makes lightning the undisputed number one cause of destructive surges and surge-related failure.

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Utility grid switching – Power is not generated from a single power station but from many locations. The utility company, therefore, instead of altering generating equipment operation, switches power across the grid as required. This switching of the power on the grid, in turn, creates transient surges that flow down the transmission lines.

cycling of power on equipment – Surges caused by the intentional or unintentional switching of power to equipment, although the least extreme, are the most frequent cause of surges. These nominal surges damage equipment over a longer period and are less noticeable to the end-user.

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Electrical noise- Is the result of more or less random electrical signals getting coupled into circuits where they are unwanted, i.e., where they disrupt information-carrying signals. Noise occurs on both power and signal circuits, but generally speaking, it becomes a problem when it gets on signal circuits. Signal and data circuits are particularly vulnerable to noise because they operate at fast speeds and with low voltage levels. The lower the signal voltage, the less the amplitude of the noise voltage that can be tolerated.

Equalization of earth potential differences through copper cable-This is the most common source of failure in exterior HUB type of designs.

 

How does S.T.E.V.E solve these problems?

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Transient Surge Arrestors – This class of surge arrestors function by creating a low impedance path to ground, should the voltage exceed its particular rating. Examples of these are gas arrestor tubes, silicon avalanche diodes, and metal oxide varistors.

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Isolation transformers – By utilizing an isolation transformer, the equipment has no physical connection to the primary feed. Isolating the connection provides increased resistance to surges, eliminates ground looping and when used in conjunction with an earth screen, reduces capacitive conducted noise dramatically.

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Earthing- All equipment running on a STEVE is bonded ensuring that no earth potential differences are present.

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The S.T.E.V.E units are site-specific and customizable in 200VA Increments, up to 10KVA

Outputs are as per site requirements,

The specifications below are for a typical single-phase STEVE:

 

SPD according to EN 61643-11 / IEC 61643-11 type 2 / class II

Energy coordination with terminal equipment (≤ 10 m) type 2 + type 3

Nominal voltage (a.c.) (UN) 230 V (50 / 60 Hz)

Max. continuous operating voltage (a.c.) [L-N] (UC) 320 V (50 / 60 Hz)

Max. continuous operating voltage (a.c.) [N-PE] (UC) 255 V (50 / 60 Hz)

Nominal discharge current (8/20 µs) (In) 20 kA

Max. discharge current (8/20 µs) (Imax) 40 kA

Lightning impulse current (10/350 µs) [N-PE] (Iimp) 12 kA

Voltage protection level [L-N]/[N-PE] (UP) ≤ 1.5 / ≤ 1.5 kV

Voltage protection level [L-N] / [N-PE] at 5 kA (UP) ≤ 1.2 / ≤ 1.5 kV

Follow current extinguishing capability [N-PE] (Ifi) 100 Arms

Response time [L-N] (tA) ≤ 25 ns

Response time [N-PE] (tA) ≤ 100 ns

Max. mains-side overcurrent protection 125 A gG

Short-circuit withstand capability for max. mains-side overcurrent

protection (ISCCR) 25 k Arms

Temporary overvoltage (TOV) [L-N] (UT) – Characteristic 335 V / 5 sec. – withstand

Temporary overvoltage (TOV) [L-N] (UT) – Characteristic 440 V / 120 min. – safe failure

Temporary overvoltage (TOV) [N-PE] (UT) – Characteristic 1200 V / 200 ms – withstand

Operating temperature range (TU) -40 °C ... +80 °C

DC Output Options: 3.3, 5.0, 9.0, 12.00, 24.00, 48.00

AC output Options: 24AC, 36AC, 48AC, 220AC

Temporary overvoltage (TOV) [L-N] (UT) – Characteristic 335 V / 5 sec. – withstand

Temporary overvoltage (TOV) [L-N] (UT) – Characteristic 440 V / 120 min. – safe failure

Temporary overvoltage (TOV) [N-PE] (UT) – Characteristic 1200 V / 200 ms – withstand

Operating temperature range (TU) -40 °C ... +80 °C