2
Product description for safety module CAMC-G-S1
Festo – GDCP-CAMC-G-S1-EN – 1412b – English
17
Discrepancy time
The transition between the safe and the unsafe state is initiated via level changes at the control ports
STO-A and STO-B of the safety module CAMC-G-S1. According to the safety function specification, the
two levels must be identical otherwise an error message will be generated. The finite state machine in
the motor controller internally monitors the driver supply voltage after the control ports have been
activated. Due to component tolerances or bouncing safety controller ports, for example, these level
changes do not normally occur precisely at the same time. The firmware tolerates this for as long as the
second input occurs within a defined time, the so-called discrepancy time. If this time is exceeded, the
motor controller generates an error message.
The default discrepancy time is 100 ms.
Recommendation: Always switch STO-A and STO-B simultaneously.
Test pulse
Temporary test pulses from safety controllers are tolerated and thus do not trigger the STO function.
The tolerance to test pulses from sensors with OSSD signals is rated for the operating range specified
in accordance with Appendix A.1.4, Tab. A.9. The permissible test pulse length is dependent upon the
control voltage level at inputs STO-A and STO-B.
Example:
Input voltage for STO-A and STO-B = 24 V
è
OSSD signals with a test pulse length of 3.5 ms are tolerated.
2.2.4
Feedback contact C1, C2 [X40]
If the
STO function is inactive
, the feedback contact opens. This is the case, for example, when only
one of the two control voltages STO-A or STO-B is present, if the 24 V logic power supply is switched off
or if the supply voltage fails.
When the
STO function is active
, the relay contact is closed.
The feedback contact has a single channel and may be used for diagnostic purposes, but
not in the safety circuit.
Tab. A.10 Appendix A.1.4 describes the electrical data, Tab. A.9 the time response of the
feedback contact.
When the 24 V supply to the basic device is turned on and off, the switching status of the
relay may – due to the internal supply voltages powering up at a different speed – deviate
briefly (approx. 100 ms) from the state of the control ports STO-A and STO-B.
2.2.5
Auxiliary supply 24V, 0V [X40]
The motor controller CMMP-AS...-M3 with safety module CAMC-G-S1 provides a 24 V auxiliary supply to
[X40]. This can be employed when using the feedback contact C1/C2 or to supply external, active
sensors.
Tab. A.11 Appendix A.1.4 describes the electrical data for the auxiliary supply.
