Utility engineers and contractors need phase information for a wide variety of projects, ranging from system improvement to expansion for new housing developments. By quickly identifying the phase at a specific point of interest, the AP-10 offers a convenience compared with traditional phase-determination methods, which have required either de-energizing the lines or visually following the three lines (phases A, B, and C) from a substation while driving a crew truck to the point in question.
Replacing this error-prone, costly practice translates to productivity gains and significant cost savings, and even puts many previously unfeasible assessment and improvement projects within reach.
The AP-10 identifies phase and phase angle on all overhead conductors, such as power lines, and on vault and pad-mounted switchgear. The system handles 120 volts to at least 345 kilovolts and is designed to allow easy one-person operation.
Beta and pre-commercial versions of the AP-10 have been in use since early 2003 at several utilities around the US. Completed and anticipated uses include system mapping and verification, electromagnetic field modeling, phase verification on automated distribution switches, underground system expansion, and phase identification where underwater line extensions resurface.
The product is comprised of three components: a reference unit, kept at a substation; and a field unit and hotstick unit, which go to the job site. When touched by a live conductor, the hotstick unit transmits a reading to the field unit, which then calls the reference unit using a built-in cell modem to perform the phase calculation and provides successive phase readings in seconds each.
When out of cell range, the device stores a reading to let the user drive to cell range, then automatically dials the reference unit and completes the phase calculation.
