Appendix Esil-2 Features; Safety Relevant Parameters; Guidelines For Configuring, Installing, Operating, And Service - Emerson Rosemount 975UF Reference Manual

Reference Manual
00809-0100-4977
E SIL-2 features
This appendix details the special conditions to comply with the requirements of EN 61508
for SIL 2.
The Rosemount 975UF Flame Detector can only be used in low or high demand mode
applications; see IEC 61508.4, Chapter 3.5.12.
E.1

Safety relevant parameters

Perform the following functional checks of the detector every thirty days.
• HFT: 0
• PFD: 1.9 x 10
• PFD: 1.9 x 10
• SFF: 97% fulfills the conditions of EN 61508 for SIL2.
E.2 Guidelines for configuring, installing,
operating, and service
The alert conditions according to SIL-2 can be implemented by an:
• Alert signal via 20 mA current loop
or
• Alert signal via alarm relay and the fault relay
E.2.1 Conditions for safe operating
1. The flame detector shall consist only of the approved hardware and software
2. The 24 V power supply must fulfill the requirements for PELV/SELV of EN 60950.
3. The automatic built-in test (BIT) must be activated.
4. The setup parameters must be verified (as described in
5. The function of the Rosemount 975UF Flame Detector (flame detector, function of
E.2.2 Using the 0-20 mA interface for alerting
The following parameters shall be set:
• Automatic built-in test: On
Rosemount 975UF
-4
(≈ 2% of SIL-2) if only alarm relay is used for alerting.
-4
(≈ 2% of SIL-2) if 0-20 mA - interface is used as alarm.
modules.
for alerting and Using the alarm relay contact for
Rosemount 975 flame detector (flame detection, function of the 0-20 mA interface,
relay functions) must be checked completely.
the 0-20 mA interface, and relay functions) must be checked completely.
SIL-2 features
Using the 0-20 mA interface
alerting), and the function of the
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