Safety as an integral part – arc resistance

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The arc barrier restricts the effects to one cubicle in case of arcing.

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Insulated main busbars prevent the occurrence of arcing.

Besides the reliability of power supply, a high level of personal protection plays a central part.

Protection for people and plant

An arc is one of the most dangerous faults, associated with the most serious consequences which can occur inside a switchboard, and it can also damage adjacent feeders, cubicles or the entire switchboard. Arcing can be caused by incorrect dimensioning and reductions in insulation due to pollution, etc., but it can also be the result of handling errors.

The effects, resulting from high pressure and extremely high temperatures, can have fatal consequences for the operator, the switchboard and even the building. Testing of low-voltage switchboards under conditions of arcing is a special test in accordance with IEC/TR 61641. SIVACON S8 offers the verification of per- sonal safety by testing under conditions of arcing. Furthermore, SIVACON S8 has passed the more severe test according to AS/NZS 3439.1 (Australian/New Zealand standard).

Your benefit

  • Personal safety by testing the switchboard under conditions of arcing

  • Plant safety by limiting the effects of internal arcing faults inside the switchboard

  • Reliability thanks to extensive systematic check

Arc protection levels

For SIVACON S8 with requirements concerning the arc resistance, Siemens has developed a level concept. The arc protection levels describe the limitation of the effects of an arc on the entire switchboard or parts thereof.

Level 1

Level 2

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Personal safety without extensive limitation of the arcing fault effects inside the switchboard.

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Personal safety with limitation of the arcing fault effects to one cubicle or double-front unit.

Level 3

Level 4

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Personal safety with limitation of the arcing fault effects to the main busbar compartment, to the device compartment, or to the cable compartment in one cubicle or double-front unit.

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Personal safety with limitation of the arcing fault effects to the place of origin.

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Tests under conditions of arcing in accordance with IEC/TR 61641

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Arc resistance measures are an integral part of SIVACON S8.

Safety as the primary objective

Preventive protection measures such as the high-quality insulation of live parts (e.g. busbars), standardised and simple operation, integrated operating error pro- tection and reliable switchboard dimen- sions prevent arcing, and thus personal injuries.

Moreover, reactive protective measures limit the effects of an arc. They include: arc-resistant hinge and locking systems, safe operation of withdrawable units or circuit breakers behind a closed door, and protective measures on ventilation openings at the front, arc barriers, or an arc detection system combined with the rapid disconnection of arcs. The func- tionality of the measures described has been proven by numerous, comprehen- sive arcing tests under “worst-case” con- ditions, performed on a wide variety of cubicle types and functional units.