8 Operation
Maschinenfabrik Reinhausen GmbH 2020
102
6385142/08 EN
ETOS
®
ED
8.3 Operating the motor-drive unit with the hand crank
WARNING
Danger of explosion!
Unauthorized operation of the motor-drive unit with the hand crank may re-
sult in death or serious injury.
► Never operate the motor-drive unit electrically or with the hand crank be-
fore the transformer has been disconnected if you think there may be a
fault in the transformer or on-load tap-changer / de-energized tap-
changer.
► Never use the hand crank to complete a tap-change operation that has
begun electrically, but has not been ended completely.
► If the hand crank is difficult to move, you must stop using it.
► When operating the motor-drive unit with the hand crank, never reverse
the direction of rotation.
► If there is any doubt about the on-load tap-changer / de-energized tap-
changer being in proper working condition or about the cause of a fault in
the motor-drive unit, contact the Technical Service department of Maschi-
nenfabrik Reinhausen GmbH immediately.
► To operate the motor-drive unit manually, only use the hand crank
mounted in the motor-drive unit.
For information about fault rectification, refer to the "Fault elimination" chap-
ter.
Normal operation
During normal operation, there is no need to operate the unit with the hand
crank. The hand crank is mainly required during installation and for tests in
the transformer plant.
Use of the hand crank for operating the motor-drive unit is permitted if the
transformer is disconnected, e.g. for maintenance tasks, if there is no de-
tectable fault on the transformer or on-load tap-changer / de-energized tap-
changer and the previous tap-change operation has been completed cor-
rectly.
Emergency operation exception
An operation is considered an emergency operation if a tap-change opera-
tion is absolutely necessary when a transformer is energized, despite a fault
in the motor-drive unit. In this case, be sure to observe the warnings listed
above.
Operating the motor-drive unit with the hand crank
To carry out a tap-change operation with the hand crank, proceed as follows:
1. Open the door of the protective housing for the motor-drive unit.
2. Switch off motor protective switch Q1 (position 0).