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IM 12D08N05-01E
5-12
<5. MENU STRUCTURE COMMISSIONING>
100
50
0
ton
toff
50%
50%
% controller output
Range
Duty cycle
ton > 0.1 sec
Duty cycle
toff > 0.1 sec
Duty cycle
Figure 5.4 Duty cycle control
100
50
0
% controller output
Range
0.3 s
Maximum pulse frequency
50% pulse frequency
No pulses
0.3 s
Figure 5.5 Pulse frequency control
l
Lifetime contacts
One should note that the lifetime of the contacts is limited (10
6
) When these contacts are
used for control (pulse frequency or duty cycle with small interval times) the lifetime of
these contact should be observed. On/Off control is preferred over Pulse/duty cycle.
5.8 Fail
A fail contact is energized when a fail situation occurs. Fail situations are configured in
section 5.12. For SOFT Fails the contact and the display on LCD are pulsating. For HARD
Fails the contact and the display on LCD are energized continuously.
Only contact S4 is programmed as a fail-safe contact. This means that contact S4 will be
de-energized when a fail situation occurs.
Hard Fail Only
The contact reacts to Hard Fails Only
Hard + Soft Fail
The contact reacts to Hard and Soft Fails