• AC mitigation device

Buried pipelines running parallel to high voltage AC power transmission systems can be adversely affected by the close proximity of these overhead lines.

AC Mitigation Devices are used when AC interference is so caused on a pipeline. Because of the inductive coupling, AC voltages between the pipeline and surrounding soil are unavoidable.  Induced voltages can reach dangerous levels, causing both a safety hazard to pipeline operating personnel and a risk of corrosion of the pipeline.

The units act as blocking devices to DC voltages but allow the discharge of AC current through the earths connected to them, thereby reducing AC interference effects without compromising the pipeline’s cathodic protection system. Standard cables are 2 metres long 16mm² black, green/ yellow.  Other cable types, lengths and sizes can be supplied to suit customer’s specific requirements.

Additional information:

  • Maximum permissible safety voltages up to which personnel and equipment can be exposed are defined in international safety codes and standards.
  • It is necessary to give consideration to earthing measures to keep the magnitude of AC voltages within acceptable limits.
  • Weights & dimensions :
  • :
  • Weight : 4.4 kg including 2m cable tails
  • Dimensions : (approx) 280mm long x 125 mm diameter
  • DC Characteristics :
  • :
  • Diode reverse voltage : 1600V (2 x 800V)
  • DC current average : 35A (nom)
  • Peak current 10mS : 1300A
  • Surge energy current : 8450A
  • Voltage across device for 1mA current flow : > 0.9V forward/reverse
  • Voltage across device for 10mA current flow : >1.1V forward/reverse
  • DC Characteristics :
  • :
  • Xc of capacitor (100,000microF) @ 50Hz : 31.83MOhms
  • ESR of capacitor @ 100Hz : 5MOhms
  • Impedance of device @ 50Hz : 40 MOhms (estimated)
  • AC current for 1mA current through diodes : 15A
  • AC current for 10mA current through diodes : 20A
  • Commodity Code : 9027801100