SIGMATEK ST 151, Manual

Page: 35 / 48

S-DIAS STEPPER MOTOR OUTPUT STAGE ST 151
02.12.2019 Page 33
The main power supply for the servo amplifier must be disconnected using the main switch
for the following instances:
•
Cleaning, maintenance or repairs
•
Extended still-stand periods
Failure to follow the above safety measures can lead to severe injuries.
8.1 STO
The stepper motor output stage supports the safety functions STO (Safe Torque Off), and
meets the requirements for Category 4 Performance Level "e" according to EN ISO 13849-
1 and SIL3 according to EN 62061.
For his purpose, the output stage has two safe inputs ENABLE 1 and ENABLE 2.
For the 24 V supply, only PELV/SELV can be used.
8.2 Function
The safety functions in the stepper motor output stage are controlled over two digital inputs.
The following table shows the status that the safe inputs ENABLE 1 and ENABLE 2 must
assume to enable normal operation or trigger the safety function.
Input Status Description
ENABLE 1 ENABLE 2
Open Open
Safe status of
the drive system
Open Low
Low Open
Low Low
High High
Drive system ready
If the ENABLE 1 and ENABLE 2 are changed from any status to the "Drive Ready" status,
the stepper motor output stage is not enabled immediately. In order to set the system to
“Drive system ready” status, a change from “Low - Low” to “High - High” must occur.