Power Supply Unit (Psu); Connectors - Siemens 7SR105 Rho User Manual

3. Press ENTER key to confirm.
The Stop delay count-down starts and reaches to zero.
4.
The configured BO and LEDs for the STOP MOTOR control functions will operate.
5.
6. Press RESET button to reset LED and BO states.
Repeat the same procedure for START MOTOR control logic operation.
NOTE:
If the "Control Password" is already configured in the settings, use the control password to execute the Motor
Start/Stop via control keys. For more information about the Control Password function, see
NOTE:
If the operating mode of 7SR105 Rho Motor Protection Relay is "Remote", the user can perform the Motor
Start/Stop operations when the "FUNCTION KEY CONFIG" setting is enabled.
2.4

Power Supply Unit (PSU)

The relay is supplied with the following nominal power supply ranges:
• 44 V AC/DC BI threshold available with 60 V to 240 V AC/DC power supply version
• 19 V DC BI threshold with 24 V to 60 V DC power supply version
The power supply module is equipped with 6 Binary Inputs. It 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.
In the event of the supply voltage levels are falling below the relay minimum operate level, the PSU will
automatically switch off itself and latch out and this prevents any PSU overload conditions occurring. The PSU is
reset by switching the auxiliary supply off and on.
2.5

Connectors

In 7SR105 Rho Motor Protection Relay, all the connectors are pluggable type except the CT connectors and it
consists of Binary Inputs and Binary Outputs connectors. The connector terminals are designated suitably.
©2018 Siemens Protection Devices
7SR105 Rho Description of Operation
Section 6.9
Chapter 1 Page 12 of 57