Compur Monitors Statox 503 - Page 43

Statox 503 Control Module
Issue 10 / 2018 Page 43 of 46
Operating the Statox 503 with Statox 501 ARE or HRC Sensor
The catalytic sensors type Statox 501 ARE or HRC are considered as type A elements, see IEC 61508-2, section
7.4.4.1.2. The failure rates of these sensors has been evaluated from return shipments of the recent 15 years.
They were evaluated by SGS-TÜV Saar GmbH (Report No. M0PE0001).
Sensor λ
s
[FIT] λ
du
[FIT] λ
dd
[FIT] SFF [%] T
Proof
[h]
PFD
(0,5
*
T
Proof *
λ
du
)
ARE / HRC
0 1002,1 2818,3 73,77 4380 2,19 x 10
-3
At a hardware failure tolerance of 0 and 6 month prooftest interval SIL 2 compliance is given for ARE/HRC
sensors (see IEC 61508-2, Table 2).
A prooftest of a Statox 501 ARE / HRC sensor head must be done together with the connected Statox 503
control module. For this test, span gas must be used.
 Inhibit peripheral alarm devices in order to avoid false alarms.
 Sensor head and sensor must be checked for pollution and damage.
 The span gas concentration must be above the alarm thresholds. Use the original test gas adapter.
Check all alarm functions.
 If necessary perform a calibration see chapter 6.2
 Reactivate peripheral alarm devices.
 Observe the ambience specifications of the ARE/HRC sensor heads and their IP rating.