ABB UniGear 500R - Cable Test Equipment and Procedures

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7.3.3. Three-position disconnector operation from
OFF to EARTH position
WARNING
Before performing the following operations, ensure
that the cables are dead (Incoming/ Feeder unit) or
relative busbar side is dead (Bus-section unit).
1. Ensure that the circuit-breaker is open (Figure 96)
- A).
2. Remove the padlock (if fitted) from selector of the
threeposition disconnector (Figure 90).
3. Shift the selector to the right, hold and insert the
threeposition disconnector handle into the open
(right) socket (Figure 96) - B). The operating lever
must by fully inserted in the operating slot to the
end otherwise the interlocking mechanism can be
damaged.
4. Pull the three-position disconnector handle fully
down to the end of its movement (EARTH position)
(Figure 96) - C).
5. Remove the handle and release the selector which
will return to the central position (Figure 96) - D).
Now it is possible to close the circuit-breaker
6. The indicator of three-position disconnector
position will show EARTH (Figure 96) - E).
Note: When the three-position disconnector is in
the EARTH position, electrical tripping of the
circuit-breaker is disabled
7. Lock the selector of three-position disconnector
with the padlock, if fitted (Figure 90).
WARNING
Selecting the EARTH position does not earth the
circuit/cables. To apply the earth, the circuit-
breaker must be also closed. A padlock shall be
fitted onto the circuitbreaker opening button to
prevent inadvertent removal of the circuit earth
(Figure 89).
Figure 96: Three-position disconnector operation from OFF to EARTH position.