Function Test; Function Test (Starting Alarm); Process Safety Time - Pfannenberg DS5-SIL Instructions De Service

Tone
Operating voltage
Sounder channel
Operating voltage
Monitoring circuit
Alarm output
Fig. 9 Function time diagram with fault

4.7. Function test

For applications in 'low demand mode' with safety requirements an automatic function test should be carried out with
regular intervals. The test intervals can be seen in section
Both part systems, the sounder channel and the monitoring circuit, have separate power supply connections. This
means that a check of the function is possible and can be carried out as follows (time dependencies see
Fig. 9).
a) Switching on the monitoring power supply when the sounder channel is not activated, (can be omitted de-
pending on use if the monitoring is continuously connected to the supply)
b) Check whether the fault alarm relay has high-resistance >0.5s after switching on,
c) Switching on the sounder channel (sound is generated)
d) Check whether the fault alarm relay has switched after >0.2s (low-resistance)
e) Switching off the operational voltage of the sounder channel, the fault alarm relay must have fallen away
(high-resistance) after 2.5s at the latest
f) Switching off the monitoring (depending on use)
It is important for the system test that the change of the switch position of the alarm relay is detected depending on
the generation of the acoustic warning signal. With which distances a system test has to take place is dependent on
the eventual use in which the sounder is involved. The equipment specific check intervals must be defined in the re-
spective proof of safety.
The function test can be shortened if a tone without interrupted tones is used. Then time in point e) can be reduced to
0.3s.
It is required that a tone is selected at the DIP switch of the sounder or a tone is activated simultaneously with the
sounder from the 'external tone selection' option.

4.8. Function test (Starting alarm)

The algorithm, as described in section 4.7, must be carried out immediately before every time the machine is switched
on.
Note: in doing so the functionality of the monitoring channel (diagnosis channel) is tested according to the IEC61508
required frequency.

4.9. Process safety time

Conclusions for the required process safety time can be drawn depending on use according to the function time dia-
grams. The reaction times for the generation of the acoustic warning signal and the switching status of the alarm relay
depending on the switching on and off time of the operational voltage
mand, the warning signal is not generated,
With the connection of the operational voltage, the sounder generates an acoustic warning signal after 0.3s at the lat-
est and reports this via the alarm relay (output low-resistance). This means the 'generation of a warning signal' safety
function has been activated. Further explanations of the reaction times of the alarm relay can be found in section
Datei/ file name:085501929j de-en-fr-it.docx
Tone is not generated
4.4.2.2 .
Fig. 9) are illustrated here.
page 28 / 68
Tone cancelled
* dependent on the tone
and cause of fault
(Fig. 8) and in the case of a fault (despite de-
Fig. 8 and
4.5.
Drwg-no.: 30007-008-12j