L3447
Emax DC
26/108
L3728
Doc. No.
Model
Apparatus
Scale
Page No.
1SDH000635R0002
10.2 Mechanical locks
a-b) Lock in open position
Different mechanisms are available which enable the circuit-breaker to be locked in the open position.
These devices can be controlled by:
– a key (a): a special circular lock with different keys (for a single circuit-breaker) or with the same keys (for several circuit-breakers). In the latter
case, up to four different key code numbers are available.
– padlocks (b): up to 3 padlocks (not supplied): Ø 4 mm.
c) Circuit-breaker lock in connected - test isolated - disconnected position
This device can be controlled by a special circular lock with different keys (for a single circuit-breaker) or with the same keys (for several circuit-
breakers available up to four different key code numbers) and by padlocks (up to 3 padlocks, not supplied - Ø 4 mm).
Only available for circuit-breakers in withdrawable versions for installing on the moving part.
d ) Accessories for lock in test isolated - disconnected position
In addition to the circuit-breaker lock in the connected - test isolated - disconnected position, this allows locking only in the disconnected or test
isolated positions. Only available for circuit-breakers in withdrawable versions for installing on the moving part.
e) Accessories for shutter padlocks
They enable the shutters to be padlocked (installed on the fixed part) in the closed position.
Only available for circuit-breakers in withdrawable versions for installing on the fixed part.
f) Mechanical lock on compartment door
This prevents the compartment door from being opened when the circuit-breaker is closed (and connected in the case of withdrawable circuit-
breakers) and prevents circuit-breaker closing with the compartment door open.
Transparent protection covers
a) Protection covers for opening and closing pushbuttons
These protection covers, applied over the opening and closing pushbuttons, prevent the corresponding circuit-breaker operations except by
using a special tool.
b) IP54 door protection
This is provided by means of a transparent plastic escutcheon plate which fully protects the front of the circuit-breaker and ensures a degree
of protection to IP54. Mounted on hinges, it is fitted with a key lock.
Interlock between circuit-breakers
This mechanism makes the mechanical interlock between two or three circuit-breakers (even of different sizes and in any fixed/withdrawable version)
by means of a flexible cable. The electrical circuit diagram for the electrical changeover by means of a relay (to be provided by the customer)
is supplied with the mechanical interlock. The circuit-breakers can be installed vertically or horizontally.
4 types of interlocks are available:
type A: between 2 circuit-breakers (power emergency)
type B: between 3 circuit-breakers (2 power su emergency)
type C: between 3 circuit-breakers (2 power su bus-tie)
type D: between 3 circuit-breakers (3 power supplies / a single closed circuit-breaker)
The emergency power supply is generally supplied in order to substitute the normal power supply in two cases:
– to supply safety services for people.
– to supply essential parts of the installation, other than the safety services.
The change over from the normal supply to the emergency supply, can be done manually (with a local or remote control) or automatically. For
the change over, the circuit-breakers must be supplied with the necessary accessories for the electrical remote control and for electrical and
mechanical interlocks provided for the changing over.
The accessories can be for example:
– the shunt opening release
– the shunt closing release
– the motor operator
– the auxiliary contacts.
For the change over, the customer can use a suitable electronic relay, whose diagram is supplied by ABB SACE. The mechanical interlocks between
two or three circuit-breakers are made by means of cables that can be used for circuit-breakers installed, either side-by-side or one over the other.