ABB FSO-12, Руководство пользователя

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34 Safety information and considerations
Transient mute time, example graph
The graph below illustrates the behavior of the safe speed estimate in the transient
situations of an example application. There are spikes in the FSO module safe speed
data when the motor speed changes due to change in the motor torque.
Transient mute time with safe speed estimate:
Parameter FSOGEN.31 Transient mute time for safety function should be
according to the worst case situation, which is in this example 500 ms. This
means, that this transient mute time is applicable for all 3 situations.

Proof testing
Periodic proof testing of, for example, electromechanical parts of the safety system
may be required in order to maintain the claimed SIL / PL level of the system. In this
case proof testing must be taken into consideration in the safety calculations and it
must be properly documented in the user documentation. Proof testing has to be
verified in the acceptance testing during the commissioning phase.
The FSO module itself does not require periodic proof testing.
A SLS trip limits
B Zero speed
Actual speed
Safe speed (estimate)
1 Trip limit hit, spike duration 500 ms
2 Monitoring started (SAR1 monitoring), spike duration 70 ms
3 Zero speed detection, spike duration 20 ms
1 3
B
A
A
2
Motor speed
Time