Megger PVS 100i, Руководство пользователя

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For the purpose of this type of “remote” comparison, the PVS 100i consists of two
devices, one of which (the base station) is connected to a reference phase. The second
device (the mobile unit) can be connected anywhere in the network, and the phasing can
be determined across various voltage levels by comparing the angle of the phase
currently being tested with that of the reference phase.
Automatic comparison with a direct indication of the phase assignment takes place by
synchronising the two devices via a GSM connection. GPS is used, to provide a highly
accurate time base.
If there are one or more transformers between the base station and the test point, the
effect of these vector groups and the associated phase shifts (multiples of 30°) can be
easily taken into account by entering appropriate correction values.
The following illustration shows typical examples of how the PVS 100i can be used
within a network, regardless of voltage levels and connection options: