9. Fault diagnosis
If after power on the evaluation unit is not enabled, a system fault is assumed. In
the easiest case a connected fail-safe switch is not in the operating range.
Location by means of the indicators
Wiring and sensor faults
One way to locate wiring or sensor faults is the indication of the enable signal of
the connected inductive fail-safe switches (LED 1, see the figure on page 16).
The connected fail-safe switches can be wired pseudo-serially, i.e. the clock or the
enable signal is passed through from the first to the last connected fail-safe
switch.
If somewhere in this chain one or several faults occur, the enable signal is
interrupted starting from the first detected fault source. The LED 1 yellow
provides the information whether all connected fail-safe switches have given the
enable signal.
Internal faults
If the evaluation unit detects a fault, the unit changes to the safe state (LED 4
red, see figure on page 16).
A function test of the evaluation unit allows to check whether a hardware error is
present or whether the change to the safe state has been caused by external
faults.
To do so the evaluation has to be switched off briefly for min. 50 ms (data bit
DO0, 1= evaluation OFF, also see page 21).
Voltage supply
If after power on the LED green PWR is not lit, the supply voltage must be
checked.
Overload and short circuit of the input supply are signalled to the AS-i
master (version 2.1) via the "periphery fault" flag in the status register.
10. Maintenance/duration of use
The evaluation unit is maintenance-free. The maximum duration of use is 10
years.
G1506S
EVALUATION UNIT
PAGE
19