The content has been shared, if you want to share this content with other users click here.
The interruption occurred at 11:45am, and was caused by a failure at generator E-CL's Crucero substation, the regulator said in a statement.
Power supply was fully restored by around 5pm, according to grid operator CDEC-SING.
The outage left more than 270,000 homes without electricity.
SEC head Luis Ávila was quoted saying that the interruption was not caused by structural problems, nor a lack of generation capacity.
If it is determined that a regulatory violation occurred, Ávila said the punishment could range from a reprimand to a fine of up to 10,000 UFs (inflation-indexed units, US$434,917).
The SING covers 185,142km2 in Chile's three northernmost regions – Arica, Tarapacá and Antofagasta – with mining companies and other industrial clients accounting for about 90% of demand.
Argentina's planning ministry announced it helped cover demand in northern Chile with 126MW available from Termoandes' Salta province connection which can be increased to 300MW.
BNamericas will host its fourth LatAm Power Generation Summit in Santiago, Chile, on August 13-14. Click here to download the agenda.