Siemens UL 489 Operating Instructions Manual page 191

Settings
 Changing settings (page 9-86)
Settings ZSI module
OFF ZSI function deactivated
S ZSI module effective for short-time delayed short-circuits only
G ZSI-module effective for ground-fault protection only
ZSI-module effective for short-time delayed short-circuits and ground-fault
S+G
protection
TEST Test position for checking the ZSI functionality
Indicators
 (page 9-86)
Testing
 (page 9-86)
In addition, a special test feature of the ZSI module (rotary coding switch in TEST position) makes it possible to check the ZSI wiring and the
operativeness of the ZSI electronics.
9.2.3.3 Digital input module
Function
With the digital input module, up to 6 additional binary signals (DC 24 V) can be connected to the system.
These input signals are transferred to the PROFIBUS DP, PROFINET IO, Modbus RTU and Modbus TCP via the c, and can be
evaluated accordingly.
For trip units ETU776, it is possible as an alternative to use an input signal of this type at input 1 to switch between two different sets of pro-
tection parameters (if provided).
Installation
 (page 9-83)
Connection
 Connection setup (page 9-83)
A maximum of two digital input modules can be operated on the c at the same time
- 1 module with the "BUS INPUT" setting
- 1 module with the "PARAMETER SWITCH" setting
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