ABB VD4X, Instruction Manual

24

V D 4 X  

I N S T R U C T I O N   M A N U A L

—

Maintenance

Maintenance serves to ensure trouble-free 
operation and achieve the longest possible 
working life of the switchgear. In accordance 

with DIN 31051, IEC 62271-1 it comprises the

following closely related activities:

Inspection:

 Determination of the actual 

condition

Servicing:

 Preservation of a functional 

condition

Repair:

 Measures to restore the functional 

condition

5.1 5.1 General

Vacuum circuit-breakers are characterized by 
their simple and robust construction. They have 
a long life expectancy. Their operating mechanisms 
have a low maintenance requirement, and the 
interrupters are maintenance-free during their 
working life. There is no adverse effect on the 
vacuum, even from frequent switching of operating 
and short-circuit currents.

The servicing intervals and scope are determined 
by environmental influences, the switching 
sequences and number of short-circuit breaking 
operations.

Note

The following must be observed for all 
maintenance work:

•  The relevant specifications in section 

“Standards and specifications”

•  Notes on safety at work in section 

“Commissioning / Operation”

•  Standards and specifications in the country 

of installation

Maintenance work may only be performed by fully 
trained personnel, observing all the relevant 
safety regulations. It is recommended that ABB 
after-sales service personnel should be called 
in, at least during the performance of servicing 
and repair work.

While the work is in progress, all supply voltage 

sources must also be disconnected and secured 
to prevent reconnection.

Note

In order to prevent accidents 
(particularly injury to hands!) extreme 
care should be taken during all repair 
work on the operating mechanism, 
especially with front plate removed.

The spiral spring in the spring energy 
storage mechanism, for instance, 
retains a basic tension which is 
independent of the charging and 
discharging processes during 
switching, so as to ensure correct 
function. This spring energy can be 
inadvertently released if work is 
performed incorrectly on the spring 
mechanism!

5.1.1 Service-life

Typical life-expectancies for VD4X circuit-breakers.

Vacuum interrupter

Up to 30,000 switching cycles (see section 
“Permissible numbers of switching cycles” page 9)

Device

Up to 30,000 operating cycles, depending on 

switch type and assuming conscientiously 
performed inspection and maintenance work 
and normal operating conditions.

5.2 Inspection and functional testing

5.2.1 Switching devices in general

•  The proper condition of the switching device 

is to be verified by regular inspection

•  Inspection at fixed intervals may be waived if 

the switchgear is permanently monitored by a 
qualified personnel

•  The checks first and foremost comprise visual 

examination for contamination, corrosion and 
moisture

•  In unusual operating conditions (including 

adverse climatic conditions) and/or special 
environmental pollutions (e.g. heavy 
contamination and aggressive atmosphere), 
inspection may also be necessary at shorter 
intervals

•  If an incorrect condition is found, appropriate 

servicing measures are to be initiated

5.2.2 Stored-energy spring mechanism

Functional testing of the operating mechanism 
is to be performed:

•  after 5,000 operating cycles or
•  during servicing work as set out in section 

“Inspection, switching devices in general”

Prior to functional testing, switch the breaker 
off and isolate the outgoing feeder.

Note

Isolate and secure the working area in accordance 
with the safety regulations specified by DIN 
VDE/IEC.

Scope of functional testing

•  Perform several switching operations under 

no-load, above all with circuit-breakers seldom 
operated in normal service

•  Switch off the charging motor (if fitted) and 

discharge the spring energy storage  
mechanism by ON/OFF switching operations

•  

Examine visual the condition of the lubrication 

on rotary bearings, sliding surfaces, etc

•  

Check the proper mechanical/electrical sequence 

of the individual functions

5.2.3 Breaker pole

No inspection of the breaker pole above and 
beyond the stipulations of section “Inspection, 
switching devices in general” is necessary.

5.3 Servicing

5.3.1 Switching devices in general

All parts which are located within the gas 
compartment and are therefore inaccessible 
require no maintenance.

5.3.2 Stored-energy spring mechanism

Servicing of the operating mechanism is to be 
performed after 10,000 operating cycles.

Prior to servicing, open the circuit-breaker, 
isolate and secure the outgoing feeder to 
prevent reconnection.

Scope of servicing

•  Switch off the charging motor and release the 

spring energy storage mechanism by closing 
and opening the breaker

•  As a precaution, replace parts subject to high 

climatic and mechanical stresses

•  For replacement of highly stressed 

parts, release the pretension of the 
spiral spring, noting the 
pretensioning dimension. Take care 
when handling springs

• Relubricate pawls, support shafts, 

sliding and rotating bearing surfaces. 

Lubricant: Isoflex Topas NB 52

•  Check the fit of fasteners (e.g. locking 

pins) in cranks, pins, bolts etc. Check 
the tightness of fastening bolts

•  Always replace any spring lock 

washers, split pins and other 
fasteners removed during the work 
with new parts when reassembling 
the equipment

•  Check the general condition of the 

operating mechanism and recharge 
the spring to the pre-tensioning 
dimension noted

•  Perform comprehensive mechanical 

and electrical functional tests 
(Observe the setting instructions)

Note

Above mentioned work may only be performed 
by servicing personnel from ABB or adequately 
trained specialist staff.

5.3.3 Breaker pole

The breaker pole with the vacuum interrupter is 
maintenance-free up to the permissible number 
of operating cycles as sent down in section 
“Permissible number of vacuum interrupter 
switching operations”:

•  When the permissible number of operating 

cycles as a function of the breaking current has 
been reached, the vacuum interrupters are to 

be replaced (see section 2.3)

Note

The above activities may only be performed by 
servicing personnel from ABB or adequately 
trained specialist staff, as they require work on 
the circuit-breaker itself.

5.4 Repair

5.4.1 Run-on block

Should irregularities occur in the area of the 
internal control mechanism and the charging 
function of the spring energy storage mechanism, 
a run-on block blocks the next closing operation 
in sequence.

This is a protective function to prevent damage 
to the circuit-breaker.

Release of the run-on block may only be performed 
by servicing personnel from ABB or adequately 
trained specialist stuff.

5.4.2 Replacement of circuit-breaker parts and 

ac cessories

•  Only remove and reassemble circuit-breaker 

parts and accessories when the breaker has 
been switched off and the working area 
properly isolated and secured to prevent 
reconnection. The spring energy storage 
mechanism must be discharged

•  All supply voltage sources must be 

disconnected and secured to prevent 
reconnection during the removal and 
installation work

•  Connecting and adjusting elements 18 and 18.1

to 18.4 (see Figure 3/1) must be removed, inter

alia, prior to removal of the circuit-breaker 
operating mechanism

•  

Only use original parts when replacing defective 

components