Spectrex Xenon 700 SIL Open-Path Gas Detection System - Manual (Page 73)

Safety relevant parameters (700S) 61
C Special Conditions to Comply to SIL-2
Requirements
➣ In this appendix…
Safety relevant parameters (700S) page 61
Guidelines for Configuration, Installation,
Operation and Maintenance page 61
Miscellaneous page 62
Special conditions to comply with the requirements of EN 61508 for SIL-2
This appendix details the special conditions to comply with the requirements
of EN 61508 for SIL-2. The SafEye 700S can be used in low or high demand
mode applications, see IEC 61508.4, Chapter 3.5.12.
C.1 Safety relevant parameters (700S)
Perform the following functional check of the detector half yearly:
(see chapters Periodic Maintenance and Function Check of Unit)
 HFT: 0
 PFD: 3.3 x 10 -4 (3.3% of SIL-2)
 PFH: 1.5 x 10 -4 (15% of SIL-2) - For 0-20mA signal current application.
 SFF: Fulfills the conditions of EN 61508 for SIL-2.
C.2 Guidelines for Configuration, Installation,
Operation and Maintenance
Alarm conditions complying with SIL-2 can be implemented only with
0-20mA outputs.
C.2.1 Conditions for Safe Operation
 The SafEye 700S shall consist only of the approved hardware and
software modules
 The 24C power supply must comply with the conditions for “safe low
voltage” according to EN 60950 (PELV / SELV).
 After installation and configuration the set-up parameters must be
verified and the function of the SafEye 700S (gas detection, function of
the 0-20mA interface, relay functions) must be checked completely.