ABB UniSec Operation And Maintenance Manual page 9

D I S T R I B U T I O N S O LU T I O N S
2.3 Enclosure and segregation
Material
The enclosure and internal segregations of the unit are
made of 2 mm thick galvanized steel sheet.
The doors and end plates are accurately cleaned and
treated against corrosion before being painted with
high-quality coatings. RAL 7035 colour paint is used for
the top coat (other colours can be provided, subject to
agreement). The cable compartment doors are
pressure-resistant and equipped with inspection
windows. The auxiliary circuit compartment for the
secondary equipment is completely protected from the
high voltage area by metallic segregation.
Cable nd circuit-breaker compartment
The high voltage compartment (circuit-breaker or cable
compartment) is equipped with an inspection window.
Neighbouring units are segregated from the other by
its respective walls. The front of the unit is closed by a
pressure-resistant removable door. On the sides of the
end units, cover plates ensure a good appearance and
are mechanically and thermally arc proof
Ventilation openings
Openings in the outer enclosure are needed for
ventilating the extra heat, which may be generated in the
busbars and branch connections. The gas exhaust flaps
form the ventilation openings for the units.
2.4 General information about
interlocks
The interlocks are designed to prevent incorrect
operations, thereby ensuring a higher level of safety
for both personnel and the installation. The interlock
function operates even when the doors of the cable
compartment, operating mechanism compartment
and apparatus compartment are open.
Purpose
The purpose of the interlocks is to prevent the switch-
disconnector and earthing switch from being
operated incorrectly, thereby ensuring safe conditions
for the operators. The interlock function operates
even when the doors of the cable compartment and
operating mechanism compartment are open.
Interlock function
The interlock function includes:
• normal interlock: standard equipment installed on all
the units
• supplementary interlocks: these are optional and
must be chosen by the customer.
Interlock for LSC2A-PM units
Positions
The switch-disconnector units and combined
switch-fuse and breaker units have two holes for
operating the switch-disconnectors:
• top hole for the "open" and "closed" position
• bottom hole for the "earthed" position.
Interlock between the operating lever of the
switch-disconnector and the motor
This is an electrical lock that prevents the motor
from functioning when the operating lever is in the
seat of the line and earth switch-disconnector.
If a motor-operated control is installed, the spring is
loaded by a motor operated by push-buttons on the
panel front. Insertion of the operating lever, which
can only be performed in the open - closed positions,
acts on a microswitch which cuts off the power
supply to the motor, thus preventing it from
operating.
Locking devices
The padlock prevents the operating lever from being
used in any position ("closed", "open", "earthed").
Earthing switches
The interlock also applies to the earthing switches used
to earth the bottom of the fuses and current
transformers. These disconnectors are mechanically
connected to the operating mechanism of the GSec
switch-disconnector and function at the same time as
the GSec when this is switched between the "open" and
"earthed" positions.
Door open
The GSec switch-disconnector is locked in the
"earthed" position until the door is closed.
Supplementary interlock function
Interlocks
• For separate units, the interlock function between
the circuit-breaker and GSec can be obtained by
key interlocks.
• The interlock function can be controlled by a
microswitch when the motor is activated
• Double key interlock on the GSec switch-
disconnector. Supplementary interlocks, such as
Ronis and Profalux, are also available.
Interlocks per type of unit
Interlock
Unit l1 l2
•
SDC, SDS
SFC, SFS, SBC,
•
SBS
DRC
Table 6. the different interlocks available
9
l3 l4 l5
• •
•