Shunt Faults on Seacom and WACS

By Rudolph Muller, MyBroadband
March 13, 2020

There are shunt faults on the Seacom and WACS submarine cable systems which will require downtime to repair.

A shunt fault occurs in submarine cables when the cable insulation becomes damaged and causes a short circuit as the metallic core is exposed to seawater.

This type of fault will not cause system downtime as long as the power feed equipment can produce the additional voltage required to maintain the same current.

While there is no immediate downtime, shunt faults must be repaired within a reasonable amount of time to avoid causing problems down the line.

Fixing a shunt fault requires the submarine cable to be pulled up, which will create a typical outage of between one and three days.

Seacom shunt fault

Seacom confirmed that there is a shunt fault on its submarine cable in the Red Sea near Egypt.

The shunt fault is not currently causing any impact to traffic on the Seacom cable system but will need to be repaired as soon as possible.

Repair time will depend on repair ship availability, regulatory, and permitting approvals, as well as other factors such as weather.

“The actual repair of any shunt fault on a subsea cable means that the cable will need to be powered down while it is repaired,” Seacom said.

It added that this means that the cable cannot carry any traffic on the segment under repair.

Seacom told MyBroadband that repairing a shunt fault can take anywhere from 24 to 72 hours, depending on the nature of the fault and its location.

“As our international network has resiliency on other cable systems, the majority of traffic on the cable system under repair gets switched onto other subsea cable routes,” Seacom said.

“However, some customer services will be impacted during the repair work, which is done under a Planned Maintenance Event”.