| |
UN, UP
|
 |
| VOLTAGE RELAYS |
| |
| Application |
| |
|
The voltage relays find wide scope of applications in:
- the protection of electric power systems (transformers, generators
etc.)
- signalling the network voltage conditions for equipment cut-out or
close-in as protection from failures
- schemes of local transformer substation control (automatic close-in
or cut-out of stand-by feeders, sections, etc.)
- any point where a.c. voltage value monitoring is required
The scope of applications has been further extended by the availability
of the voltage relays UN and UP with instantaneous operation (UN 10 and
UP 10) or delayed operation (UN 14 and UP 14). The operation voltage and
time delay are continuously adjustable within the setting range, so very
accurate settings of required values are possible.
|
| |
| Description |
| |
The voltage relays are independent devices
of the system for automatic control in transformer stations SAUT. As the
other units of the System the voltage relays are static devices with only
their actuating elements being electromechanical relays permitting both
direct control and signalling as well as galvanic isolation of signalling
and control power circuits from internal circuitry of the unit.
The units are housed in a standard case for surface mounting (see dimensional
drawing in fig. 3). The front plate, under a glazed cover, bears the elements
for setting of operation voltage U/Un and time delay t>, and a block
diagram with a connection diagram is printed on the cover.
Reaching of the volage value set on scale U/Un results in an intantaneous
operation of the relay "b" and of the time dely circuit t>.
Should the time delay circuit t> be activated for longer than the time
set on scale t> (0,1-6) s, relay "a" will be operated after
elapse of the set time, and its contacts closed. However, with the time
delay circuit t> activated for shorter than the time set on scale t>,
relay "a" will not be operated. |
| |
| Features |
| |
The voltage relays are all static units (integrated
circuits and discrete semiconductor components). Such construction offers
higher accuracy, faster operation, higher reliability, pick-up to drop-off
ratio very close to 1, minimum power drain and practically unlimited life
time. Having no moving parts except auxiliary relays at the output, the
unit requires no special inspection or maintenance.
The electronic circuitry is galvanically isolated from the signalling and
control circuits by an internal input transformer and a multipole electromechanical
relay of high breaking capacity at the output. The effects of pick-up
voltages from power circuits have thus been remarkably reduced. |
| |
| Technical data |
| |
|
Rated voltage
|
100V, 110, 220V; 50Hz
|
| Setting range |
0,3-1,6 U/Un
|
|
Setting accuracy
|
5%
|
|
Setting range of time delay
|
(0,1 do 6)s
|
| Accuracy of operation |
bolja od 50 ms za t<1 s
5% za t>1 s
|
| Overload capability |
2 Un
|
| Pick-up to drop-off ratio |
> 0,95 za UP
> 1,05 za UN
|
| Power drain from measuring circuit |
1 mA pri 0,3 U/UN
8 mA pri 2 U/Un
|
| Power drain from auxiliary voltage source |
oko 4W kod 110 V=
8 W kod 220 V=
|
| Operating frequency |
47 ¸ 100 Hz
|
|
| |
| How to order |
| |
- type of unit
- rated voltage Un
- auxiliary voltage Up
|
|
|