Overhauling - ABB VD4 36 Installation And Service Instructions Manual

9.3.

Overhauling

9.3.1. Interruption devices in general
Should it have been necessary to clean the devices during the
inspections, according to what is specified in par. 9.2.1., use
the following procedure:
• insulate the work area and make it safe, following the safety
regulations specified in the IEC/DIN VDE Standards;
• general cleaning of the surfaces:
– dry and eliminate light deposits of dirt with a soft dry
cloth;
– more resistant deposits of dirt can be removed using
slightly alkaline domestic type detergent or Rivolta BWR
210 type detergent;
cleaning insulating surfaces and conductive parts:
•
– light dirt: with Rivolta BWR 210 detergent;
– resistant dirt: with cold detergent type 716.
After cleaning, rinse thoroughly with clean water and dry
carefully.
Note
Only use detergents without halogens and never 1.1.1-trichloroethane,
trichloroethylene or carbon tetrachloride!
9.3.2. Tripping device: actuator and transmission system
Circuit-breakers up to 31.5 kA
To ensure correct operation of the circuit-breaker, inspection
and maintenance of the tripping devices is recommended
every 5,000 operations. For this purpose, please contact the
ABB Service office.
Complete replacement of the actuator, shock absorber and of
the other transmission system parts (shaft, main levers, safety
rings, etc.) must be carried out after 10,000 operations.
Note
Dismantling and replacement of the operating mechanism (trip box) can only
be carried out by ABB personnel or by skilled and specially trained personnel,
particularly for the necessary adjustments.
Details regarding overhauling
• When foreseen, cut of the power supply to the spring
charging motor and manually discharge the operating
mechanism spring by closing and opening the circuit-
breaker.
• Replace the parts subjected to mechanical stress or stress
due to particular environmental conditions, (contact and
ABB service centre).
Note
These operations can only be carried out by ABB personnel or by skilled and
specially trained personnel.
9.3.3. Circuit-breaker pole
The circuit-breaker pole and relative vacuum interrupter are
maintenance-free until the maximum number of electrical
operations for the type of interrupter is reached (see par.
7.2.3. Trip curves).
The operating life of the vacuum interrupter is defined by the
sum of the ultimate currents corresponding to the specific
type of interrupter in accordance with what is indicated in the
graphs of par. 7.2.3. Trip curves: when the sum of the ultimate
currents is reached, the whole pole must be replaced.
Note
Dismantling and replacement of the pole can only be carried out by ABB
personnel or by skilled and specially trained personnel, particularly for the
necessary adjustments.
25
To carry out the interrupter test without dismantling the
circuit-breaker pole, use:
– the VIDAR vacuum tester, made by the company
Programma Electric GmbH, Bad Homberg v.d.H.
To check vacuum tightness of the interrupter, the following
test values must be set on the VIDAR tester:
Rated voltage of the circuit-breaker
36 kV
The test must always be carried out with the circuit-breaker
open with the contacts at the nominal distance (36 kV )
Procedure for testing the degree of vacuum of the interrupter
of the circuit-breaker poles:
– Turn the power supply off and make the working area safe by
following the safety regulations specified in the IEC/DIN VDE
Standards;
– open the circuit-breaker;
– earth a terminal of each circuit-breaker pole;
– connect the earth terminal of the VIDAR tester to the circuit-
breaker structure;
– connect the high voltage terminal of the VIDAR tester to
the terminal of the circuit-breaker pole not connected to
earth (L1 phase) and carry out the test. Repeat the test for
phases L2 and L3.
Note
The tester connection cables can produce an indication due to the capacitive
effect. In this case the cables must not be removed.
9.4. Repairs
Replacement of spare parts and accessories must only
be carried out by ABB personnel or suitably qualified and
specially trained personnel.
Always work with the circuit-breaker open and locked so that
it cannot be closed again, with the work area insulated and
made safe.
The operating mechanism spring must be discharged.
All power supply sources must be disconnected and made
safe against any reclosing during removal and installation
work.
Should maintenance be carried out by the
customer's personnel, responsibility for the
interventions remains with the customer.
The replacement of parts not included in the "List
of spare parts/accessories" (par. 12.1.) must only
be carried out by ABB personnel. In particular:
– complete pole with bushings/connections
– actuator and transmission system
– closing spring set
– opening spring
– shock-absorber.
d.c. test voltage
60 kV