Battery knowledge · High-voltage and functional safety

Contactor arc suppression

The means by which a high-voltage DC contactor breaks current under load. Permanent magnets push the arc sideways to stretch and cool it — so many contactors are polarised and break less current in reverse — and hermetically sealed chambers filled with hydrogen or hydrogen–nitrogen gas cool the arc and keep the contacts clean.

Also called
magnetic blow-out, arc quenching, arc chute, gas-filled contactor

Example

High-voltage and functional safety: an example situation

Normal-operation current limits do not demonstrate correct contactor behavior under a welded-contact or sensor fault.

Read Contactor arc suppression alongside Arcing in this context. Current continuing through ionised gas across a gap, typically between contacts as they separate. An AC arc goes out by itself at each current zero, a hundred times a second at 50 Hz; a DC arc has no zero and keeps burning until it is stretched and cooled so far that its voltage exceeds the source’s, which makes high-voltage DC far harder to interrupt.

Use in Lemonergy

Relate protection to faults, detection and response.

This is a reference concept. No executable Lemonergy block has been verified for this term.

References & further reading

Further reading on this topic

These sources provide broader context; they are not presented as citations for every statement in this entry.

  1. ISO 26262-1:2018 — Road vehicles — Functional safety — Part 1: Vocabulary

    International Organization for Standardization · 2018

    Topic background · Scope and terminology of automotive electrical/electronic functional safety. The catalogue is not the full standard.