Technical information

3/19
1SDC210033D0202
Time delay device for undervoltage release (UVD)
The undervoltage release (UVD) can be combined with an external electronic power supply time
delay which allows circuit-breaker opening to be delayed with preset and adjustable timing if the
power supply voltage of the release either drops or fails, thus preventing untimely tripping caused
by temporary faults. The time delay must be used with the undervoltage release (UVR) of the cor-
responding voltage.
A remote control positive safety opening command can be created by connecting an opening push-
button to the UVR combined with the UVD.
UVD - Electrical specifications
Power supply Voltage [V]
24...30V AC/DC
48...60V AC/DC
110...125V AC/DC
220...250V AC/DC
Settable delay [s]
0.25 - 0.5 - 0.75 - 1 - 1.25 - 2 - 2.5 - 3
Opening time tolerance
±15%
Auxiliary contacts
Contacts which allow information about the operating state of the circuit-breaker to be routed out-
side the circuit-breaker. The following information is available:
Q
open/closed: indication of the position of the circuit-breaker power contacts (Q);
Q
trip: signalling circuit-breaker opening due to the current release tripping (owing to overload or
short-circuit), the residual current device, the opening or undervoltage releases, the emergency
opening pushbutton of the motor operator, or owing to use of the test button (SY);
Q
trip unit tripping: indicates that one of the protection functions of the electronic or thermomag-
netic trip unit has tripped (S51).
Changeover of auxiliary contacts Q (open/closed), SY (Relay tripped) and S51 (trip unit tripping)
Normal sequence
CB Open Q=12 SY=96 S51=06
CB Closed Q=14 SY=96 S51=06
Trip Sequence
(trip caused by:
- SOR,
- UVR,
- Trip Test)
CB Open Q=12 SY=96 S51=06
CB Closed Q=14 SY=96 S51=06
CB Trips Q=12 SY=98 S51=06
CB Resets Q=12 SY=96 S51=06
Trip Sequence
(trip caused by trip unit)
CB Open Q=12 SY=96 S51=06
CB Closed Q=14 SY=96 S51=06
CB Trips Q=12 SY=98 S51=08
CB Resets Q=12 SY=96 S51=06
Time delay device for
undervoltage release
Cabled auxiliary
contact
Not cabled auxiliary
contact
Cabled auxiliary contact for
withdrawable circuit-breaker
24V DC and 250V AC/DC auxiliary contacts
250V AC/DC and 24VAC/ DC auxiliary contacts are installed without the need for any screws. They
are extremely easy to fit. Simply use slight pressure in the appropriate place. The following versions
of auxiliary contacts are available: