Siemens SINAMICS S120 System Manual page 207

Reduction in the permissible total current drain when additional encoders are connected
When additional encoders are connected, the permissible total current drain (0.9 A) of the
DRIVE-CLiQ interfaces is reduced.
● Connecting SSI encoders (24 V)
The HLA module provides 900 mA to connect encoders. This current must be distributed
across the connected encoders.
– Example
● Connecting TTL encoders (5 V encoder power supply with remote sense)
The permissible total current drain of DRIVE-CLiQ interfaces is reduced by 0.5 x current
drain of the connected encoder.
– Example
Hydraulic Drive
System Manual, 04/2015, 6SL3097-4BA00-0BP1
A 24 V SSI encoder has a current drain of 150 mA; this means that 750 mA still
remains available for DRIVE-CLiQ encoders.
An additional TTL encoder at axis 2 with 200 mA current drain reduces the permissible
total current drain for all DRIVE-CLiQ interfaces by 100 mA from 0.9 A down to 0.8 A.
Hardware
6.2 Interfaces
207