This pack includes 1 additional sensor for the efergy e2 or Elite energy meter.
By purchasing 2 of these extra sensors, you can monitor 3 phase power usage.
A total of 3 sensors are required to measure 3 phase power: 2x additional sensors, plus the 1x sensor included with the efergy e2.
Note, these extra sensors are optional accessories for the
Efergy e2 Wireless Smart Electricity Meter or
Efergy Elite sold separately (1 sensor is included with the Meter).
This sensor is
not compatible with the original efergy e.one - for that model, extra sensors can be
found here.