Aventics PROFIBUS DP, Operating

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Diagnostics
38 AVENTICS | PROFIBUS DP | R402000616–BDL–001–AF
7.2.1 Grounding the valve unit and connecting the
shield
The conductive housing and also pin 5 of the data line
connections (X7P1 and X7P2) are connected via the grounding
plate and the mounting screw to the ground.
8 Diagnostics
The EXT_DIAG message, which is sent by the bus coupler to the
PLC in case of a fault, consists of 1 byte. The cause for the
diagnostic message can be discovered with the help of the LEDs
at the bus coupler or through the diagnostics bits.
8.1 Voltage monitoring
W
If the power supply is out of the tolerance the corresponding
bit position in the diagnostic byte is setting.
W
The tolerance of the sensor supply is 20 % (19.2 V to 28.8 V)
and the tolerance of the valve supply is 10 % (21.6 V to 26.4 V).
NOTICE
Risk of electrical faults
If the bus coupler has an insufficient ground connection and
strong interference occurs, this could lead to ground return
on the shield, which impedes the transfer.
O
To ensure proper grounding the grounding plate (marked
with the symbol shown in the left margin) must be
connected to the main ground.
Table 7: Diagnostic bits
Diagnostic bit 7 6 5 4 3 2 1 0
Diagnosis – – – – – – U
Valve
U
Sensor