17
7
1
11
2
3
4
10
9
8
6
5
Caption
1
Blocco a chiave
1
Key lock
2
Closing spring charging lever
3
Operation counter
4
Seat of the undervoltage release mechanical override
5
Mechanical indicator for closing springs charged/
discharged
6
Mechanical indicator for circuit-breaker open/closed
7
Closing pushbutton
8
Opening pushbutton
9
Geared motor protection circuit-breaker reset
pushbutton
10 Indicator for release trip
11 PR521 release
Fig. 6
Mechanical override of the
undervoltage release (on
request)
Undervoltage release ena-
bled. The circuit-breaker can
only be closed if the under-
voltage release is supplied
with power.
Undervoltage release disa-
bled. The circuit-breaker can
also be closed if the under-
voltage release is not sup-
plied with power.
b) Electrical charging of the closing springs
On request the circuit-breaker can be fitted with the following accesso-
ries for electrical operation:
– geared motor for automatic charging of the closing springs
– shunt closing release.
When supplied with power, the geared motor automatically recharges
the springs after every closing operation until the yellow indicator ap-
pears (7). In the case of a power cut during charging, the geared motor
stops and automatically starts charging the springs again when the
power returns.
In any case, it is always possible to complete the charging operation
manually.
In the case of an installation with several circuit-breakers with motor
operator, to avoid excessive consumption, it is advisable to charge one
operating mechanism at a time during the starting stage.
c) Circuit-breaker closing
The operation can only be carried out with the closing springs com-
pletely charged. For manual closing, press the pushbutton (7 - fig. 6).
When there is a shunt closing release, the operation can also be carried
out remotely by means of the special control circuit. Closing having
taken place is signalled by the indicator (6 - fig. 6).
In the VD4/UniAir plug-in circuit-breakers without PR521 release, the
closing pushbutton is not accessible.
d) Circuit-breaker opening
To open manually, press the pushbutton (8 - fig. 6).
When there is a shunt opening release, the operation can also be car-
ried out remotely by means of the special control circuit. Opening having
taken place is signalled by the indicator (6 - fig. 6).
6. Instructions for operating the circuit-breaker
6.1. Safety indications
The VD4 circuit-breakers guarantee a minimum IP3X de-
gree of protection when installed in the following condi-
tions:
– fixed circuit-breaker, installed behind a protective metal
net
– plug-in circuit-breaker, installed in switchgear.
Under these conditions the operator is totally guaranteed
against accidental contact with moving parts.
Should mechanical operations be carried out on the cir-
cuit-breaker outside of the switchgear, take great care of
the
moving parts.
If the operations are prevented, do not force the mechani-
cal interlocks and check that the operating sequence is
correct.
Racking the circuit-breaker in and out of the switchgear
must be done gradually to avoid shocks which may de-
form
the mechanical interlocks.
6.2.
Operating and signalling parts
6.3.
Circuit-breaker closing and opening operations
Circuit-breaker operation can be either manual or electrical.
a) Manual charging of the closing springs (fig. 6)
Repeatedly activate the charging lever (2) (maximum rotation angle of
the lever: about 90°) until the yellow indicator appears (5). Maximum
force which can be applied to the lever: <150 N.
