Front Fascia Without Flag Output; Power Supply Unit (Psu); Figure 2-2 7Sr45 Argus Relay Front Fascia Without Flag Output - Siemens 7SR45 Argus User Manual

2.2.2

Front Fascia without Flag Output

Figure 2-2
2.3

Power Supply Unit (PSU)

The relay is supplied with the following nominal power supply ranges:
• 60 V to 240 V AC/DC power supply (BI threshold - 88 V AC/DC)
• 24 V to 60 V DC power supply (BI threshold -19 V DC)
The power supply module is equipped with 2 or 4 binary inputs and binary outputs based on the ordering options.
The PSU also consists of one RS485 communication interface (half duplex) for communicating with RTUs and
parameterization of relays via remote locations.
For AC connections, the auxiliary supply is made with the live connection to positive terminal and neutral
connection to negative for consistency and safety.
If the power supply voltage levels are falling below the relay minimum operate level, the 7SR45 Argus relay power
will automatically switch over to CT power through phase CT currents.
©2018 Siemens Protection Devices Limited
7SR45 Argus Relay Front Fascia without Flag Output
Chapter 1 - 7SR45 Description of Operation
Chapter 1 Page 14 of 48