Roxtec Cable Transits : Best Practice For Sealing Substation Cables

By Chris Dodds on 12th June, 2014

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Roxtec Cable Transits : Best Practice For Sealing Substation Cables




Many power industry players suffer from humidity in their substations, caused by water ingress from badly sealed cable entries and cable ducts.

Roxtec recently solved the problem for a wind power operator using innovative Roxtec cable and duct seals, backed-up by arguments in a White Paper written by experts from EA Technology.

One of the main conclusions of the White Paper is that there is an obvious connection between flooded cable trenches and excessive humidity and that cable trenches need to be properly sealed.

The EA White Paper on “Humidity Effects In Substations” states that high relative air humidity increases the risk of partial discharge.

This is electrical discharges occurring inside or on the surface of insulation materials caused by high voltage electrical stressing of the system when equipment is energised.

Over time this can leave switchgear vulnerable to circuit failures and power outages. The shutdown of equipment may stop manufacturing processes and a failure for a large generator corresponds to a huge loss of income, potentially leaving thousands of homes and businesses without power.

All failures must also be followed by costly and time-consuming investigations, replacements and functionality tests.

Roxtec Cable Transit Seals

T&D distribute a large range of Roxtec cable transit & pipe transit sealing system.

In addition T&D can provide nationwide site surveys to assess your on-site requirement for Roxtec cable and pipe sealing transit frames.

Prevent Humidity

“Keeping water out of a substation is vital,” says Gavin Cornall of Roxtec. Rain, flood water, high relative humidity or even dust must be prevented from reaching control equipment via roofs, walls, cable ducts, cable trenches or leaking basements.

To avoid condensation caused by high humidity inside the substation, it is important to maintain a stable indoor climate through adequate insulation.

Substation Cable Transit Seals Roxtec

Otherwise, the substation must be equipped with heaters, dehumidifiers or air-conditioning.

Gavin Cornall summarizes what the optimum substation cable sealing solution should be able to handle:

  • Cable retention
  • High water ingress protection
  • High dust ingress protection
  • Ability to seal a range of cables, including sealing trefoil cables
  • Oil egress protection
  • Install in wet or high relative humidity conditions
  • New-build and retrofit

See also : Roxtec H3 Trefoil & Triplex Cable Seals For High Voltage Cable Retention

Video: Roxtec Substation Cable Seals - Triplex Cables Using H3 Cable Seal

  • Further reading :

White Paper : Humidity Effects, Partial Discharge & Loss Of Substation Power By EA Technology

Sealing Cables In High Voltage Substations Using Roxtec Cable Transits

Roxtec H3 Trefoil & Triplex Cable Seals For High Voltage Cable Retention



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Discussion subjects include cable installations, cable jointing, electrical substation, overhead line and electrical construction at LV, 11kV, 33kV and EHV.

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Roxtec Cable Sealing Transits - Humidity Effects In Substations (EA Technology Whitepaper)

Category:  Cable Transits & Duct Sealing

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