Safe Operating Stop (Sbh) - Siemens SINUMERIK 840D sl Function Manual

Safety Functions Integrated in the System/Drive

6.2 Safe operating stop (SBH)

6.2 Safe operating stop (SBH)
Description
The SBH function safely monitors the stop position (zero speed) of an axis/spindle
in closed–loop position or speed control.
When SBH is active (SGA "SBH active" = 1), operating personnel can, for exam-
ple, enter protected machine areas in the setting–up mode without first having to
power–down the machine.
An incremental encoder is sufficient to implement this function. The actual position
value is monitored for a change.
In this case, the encoder coarse position must be taken into account for a 1–en-
coder system (see Chapter 5.4 "Actual value conditioning").
Features
The features of the SBH function are as follows:
S The axis remains in closed–loop control
S Parameterizable SBH tolerance window
S STOP B is the stop response after SBH has responded
Zero speed tolerance
The standstill of the axis/spindle is monitored using an SBH tolerance window that
is parameterized using the following machine data:
for 840D sl:
MD 36930: $MA_SAFE_STANDSTILL_TOL
for SINAMICS S120:
p9530: SI motion standstill tolerance (Control Unit)
Note
The width of the SBH tolerance window should be based on the standstill (zero
speed) monitoring limit and should lie slightly above it. Otherwise, the standard
monitoring functions of the control could be ineffective. In this case, the encoder
coarse position must be taken into account for a 1–encoder system (see Chapter
5.4 "Actual value conditioning").
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SINUMERIK 840D sl/SINAMICS S120 SINUMERIK Safety Integrated (FBSI sl) – 05.2008 Edition
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05.08