Emerson 3098 User Manual
3098 Technical Manual
Contents
Cont-5
Contents
Chapter
1 Introduction
1.1 Specific
gravity
measurement ............................................................................................. 1-2
1.2 Functional
description ......................................................................................................... 1-3
1.2.1 Meter
sensing
element .......................................................................................... 1-4
1.2.2 Installation ............................................................................................................. 1-4
1.3 Definition
of
terms ............................................................................................................... 1-5
1.3.1 Specific
gravity
(G)................................................................................................ 1-5
1.3.2
Standard (base or normal) density (
ρ
s
).................................................................. 1-5
1.3.3
Relative density (
ρ
r
)............................................................................................... 1-5
1.4 Physical
properties
of
gas compounds................................................................................ 1-7
1.5 Applications......................................................................................................................... 1-8
1.5.1 Supplementary
gas
supply .................................................................................... 1-8
1.5.2 Wobbe
index
measurement .................................................................................. 1-8
1.5.3 Consumer
gas
costing .......................................................................................... 1-8
Chapter 2
Installation procedure
2.1 Installation
procedure .......................................................................................................... 2-1
2.2 Contents.............................................................................................................................. 2-1
2.3 Installing
the
3098
enclosure............................................................................................... 2-1
2.3.1 Important
precautions ........................................................................................... 2-1
2.3.2 Connections .......................................................................................................... 2-2
2.4
Electrical connections and safety barriers / galvanic isolators............................................. 2-2
2.5
Reference chamber pressure determination ....................................................................... 2-2
2.6
Set-up procedure – purge cycling and calibration ............................................................... 2-4
2.7 Outline
dimension
drawings ................................................................................................ 2-7
Chapter 3
Electrical connections
3.1 Introduction ......................................................................................................................... 3-1
3.2 EMC
cabling
and
earthing ................................................................................................... 3-2
3.3 Certificate
conditions
for
hazardous areas .......................................................................... 3-3
3.4
Use with Signal Converters and Flow Computers ............................................................... 3-4
3.5 System
connections
(7950/7951/7955) ............................................................................... 3-5
3.5.1 7950
2-wire
configuration ...................................................................................... 3-5
3.5.2 7950
3-wire
configuration ...................................................................................... 3-6
3.5.3 7951
2-wire
configuration ...................................................................................... 3-7
3.5.4 7951
3-wire
configuration ...................................................................................... 3-8
3.5.5 7955
2-wire
configuration ...................................................................................... 3-9
3.5.6 7955
3-wire
configuration .................................................................................... 3-10
3.6
System connections (customer’s own equipment) ............................................................ 3-11
3.6.1 Non-hazardous
areas.......................................................................................... 3-11
3.6.2 Hazardous
areas................................................................................................. 3-11
3.6.3
Customer’s equipment, 2-wire configuration ....................................................... 3-12
3.6.4
Customer’s equipment, 3-wire configuration ....................................................... 3-13
3.7 Post-installation
checks..................................................................................................... 3-14