Repair; Repair Of Surface Damage; Replacement Of Components - ABB VM1 Instruction Manual

• Earth all poles of the VM1 circuit-breaker on one
side.
• Connect the earthed test lead of the VIDAR
vacuum tester conductively to the station earth.
• Connect the high voltage test lead of the VIDAR
vacuum tester with phase L1 of the unearthed
pole side and test the vacuum interrupter
chamber with the circuit-breaker contact gap
open. Repeat for phases L2 and L3.
Note:
Connected cables may lead to a "defective"
indication on the vacuum tester as a result of their
cable capacitance. In such cases, the cables are to
be removed.
7.4

Repair

7.4.1 Repair of surface damage:

Circuit-breaker part in general
• Sheet steel parts, painted:
– Remove rust, e.g. with a wire brush.
– Grind off paint coat and degrease.
– Apply anti-rust primer and top coat.
– Use a top coat in the standard colour
RAL 7035 or the relevant special colour.
• Sheet steel parts with aluminium-zinc surfaces
and chromated functional parts:
– Remove white rust, with a wire brush or
cleaning pad (e.g. Scotch-Brite, white).
– Remove loosely adhering particles with a dry
cloth.
– Apply zinc spray or zinc dust primer.
• Functional parts, phosphated:
– Remove rust, with a wire brush or cleaning
pad (e.g. Scotch-Brite, white).
– Clean with a dry cloth.
– Grease with Isoflex Topas NB 52 lubricant.
Withdrawable circuit-breaker part in general:
• Where required, regrease or thoroughly clean
slide plates and bearings in the panel and
regrease them with Isoflex NB 52 lubricant.
Remove the contact system for thoroughly
cleaning as described below (Figures 9/26 and
9/27):
– Slide the two inner annular tension springs
34.2 facing the breaker pole to a position
beside the other two outer annual tension
springs, thus releasing contact system 34.1,
and remove the contact system from contact
arm 34.
– The contact pin of the contact system and the
slot on the contact arm are to be cleaned and
greased.
16
– Fit the contact system back to front on the
thin end of arbor 39, and slide it forwards onto
the thicker part of the shank.
– Fit arbor 39 onto the relevant contact arm 34,
slide the contact system 34.1 over onto the
contact arm, and withdraw the arbor.
– Check all contact fingers and annular tension
springs for perfect fit.
Note:
The set installation position of contact arms 34
must not be changed by the improper use of
force.

7.4.2 Replacement of components

• Only remove and reassemble circuit-breaker
parts and accessories when the breaker has
been switched off and the working area is to be
isolated and secured against reclosing.
• All supply voltage sources must be disconnec-
ted and secured to prevent reconnection during
the removal and installation work.
• The storage capacitor is to be discharged in
accordance with the instructions in section 7.1.
1. Circuit-breaker control unit:
Replacement of the circuit-breaker control unit
may only be performed by ABB after-sales
service staff
personnel. Reason: the internal sequence times
for the control unit are set by jumpers on each
control unit.
2. Withdrawable assembly:
(Figures 9/10, 9/12, 9/29 and 9/30)
• Disconnect plug connector 37.
• For motorized withdrawable assemblies,
remove the two socket head bolts which are
accessible from below the assembly.
• Unbolt the
withdrawable assembly (4 x M12 bolts).
• Mount the circuit-breaker on a new with-
drawable assembly in the reverse order.
• Check the settings of the slide blocker 41.2:
– The circuit-breaker is in the ON position.
– The distance between pawl 35.5 on the
withdrawable assembly and slide blocker
41.2 must be 0.1 + 0.4 mm. If a correction
is necessary, the screws 41.3 are to be
released and the slide blocker 41.2 is to be
adjusted by a feeler gauge. Thereafter the
screws must be fixed again.
or specially trained
circuit-breaker from
skilled
the