Usf – Universal Safety Functions - Festo CAMC-G-S3 Manual

2 Product description of safety module CAMC-G-S3
2.5.6 USF – Universal safety functions
The "Universal Safety Functions" (USF) serve to monitor the status variables (path, speed
and force / torque) of the motor / the axle.
Currently available:
– The "Safe Speed Function" (SSF)
The USF function also summarises the product terms for "Request", "Terminate request",
the logical and virtual inputs and outputs (LIN_USFx..., VOUT_USFx...), as well as the
error management parameters.
4 USF functions (USF0 ... USF3) are available.
2.5.7 SSF – Safe speed functions
Application
The "Safe Speed Function" (SSF) can be characterised via the parameterisation as one of the following
safety functions:
– SLS – Safely-Limited Speed è Section 2.5.8,
– SSR – Safe Speed Range è Section 2.5.9,
– SSM – Safe Speed Monitoring è Section 2.5.10.
The specific function is then specified by a specific parameterisation of the SSF, as can be seen in the
following sections.
Each of the 4 USF functions contains an SSF function for this (SSF0 ... SSF3). This means that up to 4 of
the safety functions can be implemented and executed in parallel.
Function
The SSFs in the SLS / SSR / SSM versions monitor the speed of the drive using minimum and maximum
limits. If the speed of the motor exceeds the limit value, then the error "Safety condition violated" is
triggered.
The speed limits for monitoring are not specified statically. The SSF can calculate dynamic speed ramps
and also monitor that the drive is is performing in the desired safe speed range from any speed.
In addition, speed limiting of the motor controller can be controlled in such a way that the safety condi­
tion is not violated.
Festo – GDCP-CAMC-G-S3-EN – 1406NH – English 95