The PQUBE3 installed at my home’s incoming supply (230V Phase L3) detected an RVC (rapid voltage change) of 3.97% during the early morning of Thursday 22/02/2024.
And today, while retrieving a portable PQ monitor from one of our worksites in Banyan Drive, I noticed the following voltage trends (occurred at about the same time as my PQUBE3 event). This was recorded at 22kV.
For these 2 locations (one on the mainland in the western part of Singapore, and another on Jurong Island), to have similar voltage variations suggest that a transmission level fault had occurred during the said date/time.
We have two other sets of portable PQ monitors, one in Loyang (east of Singapore) and another in Marsiling (north of Singapore) which will be due for data retrieval next week. These PQ monitors would have similar stories to tell.
Updated – 28/2/2024
As expected, the other two set of portable PQ monitors captured the same event (at 22kV), with the PQ monitor at the northern part of Singapore saw the worst dip values, which was expected as the fault was made known to have originated from our northern neighbour (TNB – Malaysia).
Here, it can be deduced that it was a single-phase fault on the Blue phase (Phase L3).