A1.1 scope and purpose, A1.2 using rakd for a sis application, A1.2.1 safety function – Yokogawa RAKD User Manual
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<A1. SAFETY INSTRUMENTED SYSTEMS INSTALLATION>
A1-1
IM 01R01B30-00E-E 5th edition February 01, 2013 -00
All Rights Reserved. Copyright © 2003, Rota Yokogawa
The contents of this appendix are cited from exida.com safety manual on the Rotameter RAKD Flowmeter
specifically observed for the safety transmitter purpose. When using the RAKD for Safety Instrumented
Systems (SIS) application, the instructions and procedures in this section must be strictly followed in order
to preserve the meter for that safety level.
A1.1 Scope and Purpose
This document provides an overview of the user responsibilities for installation and operation of the Rota
Yokogawa RAKD variable area flow meter in order to maintain the designed safety level. Items that will be
addressed are proof testing, repair and replacement of the flow meter, reliability data, lifetime, environmental
and application limits, and parameter settings.
A1.2 Using RAKD for a SIS Application
A1.2.1 Safety Function
Suitable for use in Safety Instrumented Systems are the versions listed in table 1 only. The safety related
data listed in this manual does not apply to other versions of RAKD.
[V1]
RAKD standard – RAKD[][] - [][]SS - [][]NNN - T8[]NNN
[V2]
RAKD with head/valve– RAKD[][] - [][]SS - [][]V[][] - T8[]NNN
[V3]
RAKD with head/valve/controller – RAKD[][] - [][]SS - [][]V[][] - T8[]NNN/R[]
Table 1 Versions of RAKD suitable for Safety Instrumented Systems
This variable area flow meter is intended for use as a volume flow monitoring component in a Safety
Instrumented System. It has inductive limit switches. The flow meter may be used with the limit switches to
feed signals to a logic solver that is part of the safety instrumented function (SIF) as shown in Figure 1. The
fault annunciation mechanism is a trip of one of the limit switches. In order to take credit for the automatic
diagnostics in the flow meter, this annunciation mechanism must be connected.
Figure 1 Example Safety Instrumented Function
APPENDIX 1. Safety Instrumented
Systems Installation
WARNING