Page 453 - Offshore Electrical Engineering Manual

440 CHAPTER 2 Preparation and Use of Performance Standards

INSTALLATION: PERFORMANCE STANDARD: EMERGENCY SHUTDOWN SYSTEM (cont.)
Functions Element Assurance
1 To provide an interface with ESD a) Independent autonomous operation of ESD system. a) Test ESD intertrip signals
systems on nearby installations as per
Functional Design
Specification for Emergency
Shutdown System(s)
b) Test ESD interface
b) The ESD systems are independent autonomous systems but against appropriate Cause &
with common operator interfaces with the other process Effect Chart.
control systems and may have links with the ESD systems
of nearby installations.
2 To provide ESD Level 3 - Unit a) The ESD Level 3 (Unit shutdown) logic functions shall Functional Design
Shutdown. operate as specified on the cause and effect diagrams to Specification for Emergency
shut down systems. Shutdown System
There are two types of level 3 shutdown Function test logic functions
3 - isolation of utility or process function against the currentESD
3B - isolation of process train cause and effect chart.
and the causes and effects are described in the Safety Case.
FPSO
The ESD signals from an offloading shuttle tanker operate
shutdowns only on the export system on the FPSO and do not
affect the production train or other auxiliary marine systems.
3 To provide ESD Level 2 - Process a) The ESD Level 2 (Process Shutdown) logic functions as Functional Design
Shutdown. specified on the cause and effect diagrams to shut down Specification for Emergency
systems. Shutdown System Reference
ESD Maintenance Routines
Function test level2 logic
functions againstESD level
2 Cause and Effect Chart.
ReferenceESD Maintenance
The causes and effects of a level 2 shutdown shall be as Routines
described in the installation Safety Case.
4 To provide ESD Level 1 -Total a) The ESD Level 1 (Total Shutdown) logic functions shall Functional Design
Shutdown. operate as specified on the cause and effect diagrams to Specification for Emergency
shut down systems. Shutdown System
Function test Category 1
logic functions against a
sample from the cause and
effect chart. ReferenceESD
Maintenance Routines
The causes and effects of a total platform shutdown shall be as
described in the appropriate section of the installation Safety
Case.
FIGURE 9.2.1, cont’d