Auxiliary Power Supply; Powered By The Pr120/V Module; Environmental Characteristics; Description Of Inputs/Outputs - ABB Emax DC L3447 Installation And Service Instructions Manual

13.2.2

Auxiliary power supply

The external auxiliary power supply is provided using a galvanically-separated power pack.
Since the auxiliary voltage needs to be isolated from the ground, "galvanically separated converters" in accordance with
the IEC standard 60950 (UL 1950) or the equivalent IEC 60364-41 and CEI 64-8 have to be used to guarantee a current in
common mode or leakage current (as defined in IEC 478/1 and CEI 22/3) no greater than 3.5mA.
The presence of the auxiliary power supply enables the relay unit to be used even with the circuit-breaker open, as well as powering all the modules,
with the exception of the PR120/V-PR120/LV MEASURING module, which is powered by means of a connection to the busbars.
The characteristics of the power pack are given in the table below:
Characteristics
Auxiliary voltage
(galvanically separated)
Maximum ripple
Inrush current @ 24V
Rated power @ 24V
13.2.2.1 Powered by the PR120/V-PR120/LV module
For a full explanation of the features of the PR120/V-PR120/LV, see par. 14.1.

13.2.3 Environmental characteristics

Operating temperature
Storage temperature
Relative humidity
Degree of protection (with PR123/DC installed in the CB)

13.2.4 Description of inputs/outputs

13.2.4.1

Binary inputs

– K51/SZin (K51/DFin):
– K51/Gzin (K51/DBin):
13.2.4.2

Binary outputs

– K51/SZout (K51/DFout):
– K51/GZout (K51/DBout): Zone selectivity: output for protection G (only with Vaux)
Note: These inputs/outputs can be used between PR122/PR123 series units only.

13.2.5 Communication bus

Local internal bus on rear connector; RS485 physical interface, Modbus protocol.
External system bus, RS485 physical interface, Modbus RTU protocol, baud rate 9600-19200 bps.
Test bus on front test connector.

13.2.6 Protection functions

The PR123/DC protection unit carries out 12 independent protection functions. In particular:
1. Protection against overload with inverse time "L";
2. Protection against short-circuit with adjustable delay "S" and "S2";
3. Protection against instantaneous short-circuit "I";
4. Protection against closing on short-circuit "MCR"
5. Protection against earth fault with adjustable delay "G";
6. Protection against instantaneous short-circuit at high currents "I inst";
7. Protection against polarity unbalance "U";
8. Protection against overtemperature "OT";
9. Protection against undervoltage "UV";
10. Protection against overvoltage "OV";
11. Protection against reverse active power "RP";
12. Override protection when release is not powered.
A timing indication (message + "alarm" LED) is provided on the unit's display, which is activated during a protection alarm. It is disabled when
the alarm condition ceases or when the protection has been tripped. When the circuit-breaker opens, the page with the "Trip" data is displayed
(when "i Test" is pressed, or automatically in the presence of Vaux).
13.2.6.1

Circuit-breaker state

The PR123/DC unit records the state of the circuit-breaker by means of specific wiring on the circuit-breaker. In the case where the presence
of current is determined with the circuit-breaker in the "OPEN" state, a state error is signaled by a warning message being displayed (see par.
13.6) and the "warning" LED lighting up.
The signal can be combined with a relay of the PR120/K module or with those of the PR021/K unit.
L3447
Model
L3728
Version PR123/DC
24V DC ±20%
5%
~10A for 5ms
~5W
Zone selectivity: input for protection S (only with Vaux)
Zone selectivity: input for protection G (only with Vaux)
Zone selectivity: output for protection S (only with Vaux)
-25°C ... +70°C
-40°C ... +90°C
0% ... 98% with condensation
IP 30
Apparatus
Doc. No.
1SDH000635R0002
Emax DC
Scale
Page No.
50/108