Technical Guide
Testing self-powered relays with SVERKER 900
Page 5(33)
Figure 1. The test terminals provided by WIC-1 relay (from the WIC-
1 user’s manual [5], Copyright SEG GmbH)
and by the ABB REJ603 (
from the REJ603 user’s manual [6], Copyright ABB)
The currents are injected through the test points easily accessible from the relay. The current flows through the
special multi-winding main CTs, and it is induced back to the analog inputs of the relay. From that current, the
relay draws the energy to power itself (Figure 2).
The line/feeder must be de-energized; no primary current shall flow into the primary circuit (see par. 6.1.1 of
relay manual [5].
Figure 2. The injection in the test points L1 and N (1A in the figure) turns out to be an injection in the relay
analog inputs (S1 and S2) through the multi-winding current transformer (from the WIC-
1 user’s manual [5],
Copyright SEG GmbH). Note that the figure shows the relations for a particular CT type, which is the same used
in this document.
