Phoenix Contact AXL SE PSDI8/3, Original Operating Instructions, Page: 16 / 84

AXL SE PSDI8/3
16 / 84
PHOENIX CONTACT 108928_en_02
3.5.1 Clock outputs OUT_T1 and OUT_T2
The Smart Element has two independent clock outputs. The clock outputs supply the safe
inputs. Both clock outputs provide a pulse pattern if cross-circuit monitoring has been acti -
vated for at least one input pair. The pulse pattern is used to detect cross-circuits in the exter -
nal wiring of the inputs.

See “Cross-circuit detection” on page 44 .
Typical pulse pattern
Figure 3 - 3 Typical pulse pattern
Key:
Technical data

See “Clock outputs” on page 78 .
Behavior in the event of an
error
The clock outputs are also enabled and monitored even when the Smart Element is not
parameterized. If a short circuit occurs at a clock output when it is in this state, the clock out -
put is disabled.
In the event of short circuit to GND or overload of the clock outputs, the clock outputs are
disabled. A diagnostic message is generated. The message is indicated via the SD LED. All
the inputs assigned to the clock output are disabled.
This error must be acknowledged in order to restart the system after the error is rectified.

See “Errors: messages and removal” on page 67 .
T Test pulse width
P Period length
0
1
OUT_T1
T T T
t [ms]
0
1
OUT_T2
T T T
t [ms]
P P
P P