Fail-Safe Electronic Modules
8.1 8 /16 F-DI DC24V PROFIsafe Digital Electronic Module
ET 200pro Distributed I/O System - Fail-Safe Modules
66 Operating Instructions, 05/2007, A5E00394073-02
Assignable Parameters for Use Case 1
Set the "Evaluation of the sensors" parameter to "1oo1 evaluation" for the respective input.
You can enable or disable the "Short-circuit test" parameter. However, you must disable the
short-circuit test as soon as at least one fail-safe digital input is externally supplied.
Otherwise, the "Short circuit" diagnostic is reported.
Specific Characteristics for Fault Detection (Use Case 1)
The following table summarizes fault detection according to the sensor supply and the
parameter assignment for the short-circuit test:
Table 8-5 F-DI Modules: Fault Detection (Use Case 1)
Fault detection in case of ... Example of fault
Internal sensor supply
and short-circuit test
enabled
Internal sensor supply
and short-circuit test
disabled
External sensor
supply
Short circuit of DI 0 with DI 1 No No No
Short circuit of DI 0 with DI 4 Yes* No No
P-short circuit of DI 0 Yes No No
M-short circuit of DI 0 Yes* Yes* No
Discrepancy error - - -
P-short circuit of Vs1 Yes No No
M-short circuit of Vs1, or Vs2
defective
Yes Yes Yes
Short circuit of Vs1 with Vs2 Yes No No
Fault in read/test circuit Yes Yes Yes
Supply voltage fault Yes Yes Yes
*: Fault is detected only in case of signal corruption. That is, the signal read differs from the sensor
signal. If there is no signal corruption relative to the sensor signal, fault detection is not possible and
is not required from a safety standpoint.