Last week, two of our portable PQ analyzers captured a voltage dip of about 13% (at 22kV) lasting almost 200ms. It was made known later that it was due to a fault in the Tuas South area.
Our PQ analyzers were in the Tuas West Drive area.
Based on experience, for a voltage dip of about 10 to 20% to be seen in another 22kV network, it will need to be a significant fault causing a voltage dip in the range of 80 – 90% in the fault area (Tuas South).