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TAG Triggered Arc Gaps

The transient over-voltages caused by the effects of lightning on an overhead line distribution network can be damaging to the system equipment and inconvenient to the customer suffering from a likely loss of electricity supply.

The greatest source of over-voltage on the United Kingdom distribution system is from lightning activity. Its effect on the lower voltage networks for example at 11kV & 33kV is also very different from that on those operating at higher voltages. At 11 & 33kV most of the incidents of over-voltage due to direct strikes are far outnumbered by induced over-voltages resulting from lightning ground strikes in short proximity from the overhead line; these are known as indirect strikes.

The widespread use of surge arresters has indeed reduced some of the lightning related incidents but mainly due to direct lightning strikes. A more cost effective and reliable way to reduce lightning related incidents and damage is the rapid extinguish of over-voltages using the unique self-extinguishing properties of TAG’s (Triggered Arc Gaps). The response time of the TAG ensures that there is no upstream protection operation hence no circuit interruption or power outage is necessary to clear the over-voltage.

With many years of operational experience in the United Kingdom with over 10,000 units now in service, the TAG has proved to be an effective, reliable and inexpensive means of over-voltage protection. Potentially reducing lightning related incidents by up to 30%. Additional benefits include:

  1. Lower cost option to surge arresters
  2. Unaffected by Rain & Pollution
  3. Excellent Reliability
  4. Provides better protective level than surge arresters
  5. Simple to install (and can be installed live)
  6. Maintenance Free


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Welcome Shayden & Jack

We are delighted to welcome two new engineering apprentices Shayden & Jack to Allied Insulators. Both apprent

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