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MMI-20015440
User Manual
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Emerson Process Management MMI-20015440 User Manual

Installation and Configuration Manual
P/N MMI-20015440, Rev. AA July 2009
Micro Motion® 7827 Digital Viscosity Meter
Short and Long Stem Versions
Micro Motion pursues a policy of continuous development and product improvement. The specification in this document may therefore be changed without notice. To the best of our knowledge, the information contained in this document is accurate and Micro Motion cannot be held responsible for any errors, omissions, or other misinformation contained herein. No part of this document may be photocopied or reproduced without prior written consent of Micro Motion.
Contents
Chapter 1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Safety guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 About the meter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.2.1 What is it? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.2.2 7827 meter measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.2.3 What is it used for? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3 Principle of operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Chapter 2 Installation (Short Stem) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Boundary effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.3 Standard installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.3.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.3.2 Meter orientation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.3.3 Free stream installation - flanged fitting . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.3.4 Free stream installation - weldolet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.3.5 T-piece installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.3.6 Flow-through chamber installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2.4 Installation in the pipeline or system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2.5 Typical installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.5.1 Jacketed pipeline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.5.2 Flow-through chamber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Chapter 3 Installation (Long Stem) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
3.2 Installation considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
3.2.1 Fluid at the sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
3.2.2 Flow rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
3.2.3 Entrained gas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3.2.4 Solids contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3.3 Open-tank installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3.4 Closed-tank installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3.5 Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.6 If the Tank is Pressurized . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Chapter 4 Electrical Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.2 EMC and cabling considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.3 Installation and safety in hazardous areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
4.4 Installation in non-hazardous areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
4.5 Wiring the meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
4.6 Connecting the 7827 to a 795x series computer. . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
4.6.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
4.6.2 Connection diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Installation and Configuration Manual i
Contents
4.7 Checking the installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Chapter 5 Using 7950/7951 Processing Electronics . . . . . . . . . . . . . . . . . . . . 39
5.1 Using the 7950 / 7951 Processing Electronics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Chapter 6 Calibration Check. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
6.2 Factory calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
6.2.1 Viscosity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
6.2.2 Density. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
6.2.3 Primary standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
6.2.4 Transfer standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
6.3 In-line calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
6.3.1 Viscosity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
6.3.2 Density. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
6.3.3 Requirements for VOS correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
6.4 Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
6.4.1 Viscosity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
6.4.2 Density. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
6.5 Calibration certificate example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Chapter 7 General Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
7.2 General maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
7.3 Fault analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
7.3.1 Checking the Signal Converter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
7.3.2 Checking the power consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
7.3.3 Checking the installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Appendix A Calculated Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
A.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
A.2 Viscosity equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
A.2.1 Quality factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
A.2.2 General viscosity equation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
A.3 Density equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
A.3.1 General density equation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
A.3.2 Temperature correction equation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
A.3.3 Viscosity correction equation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
A.3.4 Pressure correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
A.3.5 Velocity Of Sound correction equation. . . . . . . . . . . . . . . . . . . . . . . . . . . 57
A.3.6 Density scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
A.4 Kinematic viscosity equation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Appendix B Safety Certification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
B.1 Safety certification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
ii Micro Motion 7827 Digital Viscosity Meter
Contents
Appendix C Product Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
C.1 Density / temperature relationship of hydrocarbon products. . . . . . . . . . . . . . . . . . . 61
C.1.1 Crude oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
C.1.2 Refined products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
C.1.3 Platinum resistance law . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
C.1.4 Density of ambient air . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
C.1.5 Density of water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
C.1.6 Velocity of sound in liquids. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Appendix D Return Policy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
D.1 General guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
D.2 New and unused equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
D.3 Used equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Installation and Configuration Manual iii
Contents
iv Micro Motion 7827 Digital Viscosity Meter
Chapter 1

Introduction

1.1 Safety guidelines

Handle the 7827 digital viscosity meter with great care.
• Do not drop the meter.
• Do not use liquids incompatible with materials of construction.
• Do not operate the meter above its rated pressure or maximum temperature.
• Do not pressure test beyond the specified test pressure.
• Ensure all explosion-proof requirements have been applied.
• Ensure the meter and associated pipework are pressure tested to 1-1/2 times the maximum operating pressure after installation.
• Always store and transport the meter in its original packaging, including the transit cover secured by grub screws.
• To return a meter, refer to the Return Policy appendix for more information on the Micro Motion return policy.
Safety messages are provided throughout this manual to protect personnel and equipment. Read each safety message carefully before proceeding to the next step.
Installation (Short Stem) Electrical ConnectionsInstallation (Long Stem)Introduction
Installation and Configuration Manual 1
Introduction
Electronics housing
Spigot
Tines
Stem (available in varying lengths)
Stem is sealed at both ends and air filled

1.2 About the meter

1.2.1 What is it?

The 7827 meter is a digital viscosity meter, based on the proven tuning fork technology of Micro Motion. It is an all-welded sensor designed to be mounted directly into a pipeline or in a tank. Viscosity and density are determined from the resonance of the tuning fork immersed in the fluid, and a temperature sensor (PRT) is also fitted within the meter.
The 7827 meter is available in a variety of materials, and the immersed tines can be laminated with PFA to inhibit the build up of residues such as asphaltenes.

1.2.2 7827 meter measurements

The 7827 meter directly measures the following fluid properties:
• Line dynamic viscosity – measured in centiPoise - cP.
• Line Density – measured in kg/m
3
.
• Temperature – measured in °C or °F.
From these properties, the 7827 meter calculates:
• Line and base (referred) kinematic viscosity – measured in centiStokes - cSt.
• Line and base (referred) density – API or Matrix.
• Referral is made to 15°C, 1.013 bar; or at 60°F, 14.5 psi.
2 Micro Motion 7827 Digital Viscosity Meter
Introduction
0dB level
-3dB level
Frequency
τ
B
τ
A
A
B

1.2.3 What is it used for?

The 7827 meter is ideally suited to applications where continuous real time measurement of viscosity is required. The meter is particularly suited where viscosity is an indication of the behavioral properties of the fluid, for example in applications involving spraying, coating or dipping.
Some uses are in the oil and petrochemical industry for:
•Refining
•Marine
•Power
• Heavy fuel oil (HFO) blending and bunkering

1.3 Principle of operation

The 7827 meter operates on the vibrating element principle, the element in this case being a slender tuning fork structure which is immersed in the liquid being measured.
The tuning fork is excited into oscillation by a piezo-electric crystal internally secured at the root of one tine, while the frequency of oscillation is detected by a second piezo-electric crystal secured at the root of the other tine. The sensor is maintained at its first natural resonant frequency, as modified by the surrounding fluid, by an amplifier circuit located in the electronics housing.
The electronics circuit actually excites the sensor into oscillation alternately at two positions on the frequency response curve as shown in Figure 1-1. In doing this, the quality factor (Q) of the resonator may be determined as well as the resonant frequency.
Installation (Short Stem) Electrical ConnectionsInstallation (Long Stem)Introduction
For details of the viscosity and density calculations, see the Calculated Parameters appendix.
Figure 1-1 Frequency response curve showing the quality factor (Q) calculation
Response
Installation and Configuration Manual 3
Introduction
4 Micro Motion 7827 Digital Viscosity Meter
Chapter 2

Installation (Short Stem)

For information on installing a long-stem version of the 7827 digital viscosity meter, see Chapter 3.

2.1 Introduction

All drawings and dimensions given in this manual are given here for planning purposes only. Before commencing fabrication, reference should always be made to the current issue of the appropriate drawings. Contact Micro Motion for details.
For further information on handling and using the meter, see “Safety guidelines” on page 1
Installation (Short Stem) Electrical ConnectionsInstallation (Long Stem)Introduction
There are a variety of external factors that affect the ability of the 7827 digital viscosity meter to operate successfully. In order to ensure that your system works correctly, the effects of these factors must be taken into consideration when designing your installation.
There are two main aspects to consider:
• The accuracy and repeatability of the measurements
• The relevance of the measurements to the overall purpose of the system
Factors which may adversely affect accuracy and repeatability include:
• The presence of gas or bubbles within the fluid being measured
• Non-uniformity of the fluid
• The presence of solids as contaminants
• Fouling of the meter
• Temperature gradients
• Cavitations and swirls
• Operating at temperatures below the wax point of crude oils
• The correct pipe diameter that corresponds to the calibration of the meter.
In some applications, absolute accuracy is less important than repeatability. For example, in a system where the control parameters are initially adjusted for optimum performance, and thereafter only checked periodically.
The term achievable accuracy can be used to describe a measure of the product quality that can be realistically obtained from a process system. It is a function of measurement accuracy, stability and system response. High accuracy alone is no guarantee of good product quality if the response time of the system is measured in tens of minutes, or if the measurement bears little relevance to the operation of the system. Similarly, systems which require constant calibration and maintenance cannot achieve good achievable accuracy.
Installation and Configuration Manual 5
Installation (Short Stem)
long axis
short
axis
Factors which may adversely affect the relevance of the measurements could include:
• Measurement used for control purposes being made too far away from the point of control, so that the system cannot respond properly to changes.
• Measurements made on fluid which is unrepresentative of the main flow.

2.2 Boundary effects

Any insertion device or meter can only measure the properties of the fluid within the region of fluid to which it is sensitive.
For practical reasons, it is helpful to consider the sensitive, or effective region, for the viscometer as an ovoid centered on the tips of the tines with its long axis aligned with the direction in which the tines vibrate, as shown below. The 7827 meter is insensitive to the properties of the fluid outside this region and progressively more sensitive to fluid properties the closer the fluid is to the tines. Density can be considered a “mass centered” effect and viscosity a “surface centered” effect in this visualization; i.e. the measurement of density is more uniformly sensitive to the density of fluid throughout the region while viscosity measurement is much more critically sensitive to fluid on the surface of the tines.
If part of this volume is taken up by the pipework or fittings there is said to be a boundary effect; i.e., the intrusion of the pipe walls will alter the calibration. The diagram below illustrates the 7827 meter installed in a pocket on the side of a 4" (100 mm) horizontal pipe line (viewed from above). The effective region is completely enclosed within the pipe line and thus is completely fluid.
6 Micro Motion 7827 Digital Viscosity Meter
Installation (Short Stem)
Top or Plan view
4” horizontal pipe
2”Schedule 40
Pocket or “T”
This next view shows other pipe outlines superimposed:
Installation (Short Stem) Electrical ConnectionsInstallation (Long Stem)Introduction
Installation and Configuration Manual 7
The smaller circle represents a 4" (100 mm) vertical pipe, which because the 7827 meter orientation is constant irrespective of pipe orientation intersects the effective region. The 6" (150 mm) pipe is the smallest pipe diameter to completely enclose the effective region when the pipe is vertical. Thus smaller pipe diameters can lead to a variety of different geometries which would each require a separate calibration.
An alternative condition is shown in the next diagram where the side pocket is extended until it passes completely through the effective region producing a “core”:
Installation (Short Stem)
From this, it would appear that almost every installation requires a separate in situ calibration – a very undesirable situation. The problem is resolved by providing standard calibration geometries which can be used in all pipe work configurations and thereby allow the factory calibration conditions to be reproduced in the process.

2.3 Standard installations

2.3.1 Overview

To overcome the need for in situ calibration for every installation, three standard installations are proposed. If an installation conforms to one of these standards, the factory calibration of the 7827 meter is valid, and in-situ calibration unnecessary. Table 2-1summarizes the three installations. For tank installations, consult Micro Motion.
Table 2-1. Types of standard installations
Installation type Free stream T-piece Flow-through chamber
Description 7827 meter tines are inserted
Flow rate 0.3 to 0.5 m/s at the 7827 meter. 0.5 to 3 m/s at main pipe wall. 10 to 30 l/min.
Viscosity 0.5 to 12500 cP 0.5 to 100 cP 0.5 to 1000 cP
Temperature
(1)
directly into the main fluid flow.
-50 to 200°C (-58 to 392°F)
7827 meter tines are contained in a side pocket off the main flow.
-50 to 200°C (-58 to 392°F)
7827 meter tines are contained in a flow-through chamber in which fluid is circulated from the main flow.
-50 to 200°C (-58 to 392°F)
8 Micro Motion 7827 Digital Viscosity Meter
Installation (Short Stem)
Table 2-1. Types of standard installations continued
Installation type Free stream T-piece Flow-through chamber
Main flow pipe size 100 mm (4") horizontal
150 mm (6") vertical, or larger.
Advantages • Simple installation in large bore
pipes.
• Ideal for clean fluids and non-waxing oils.
• Suitable for line viscosity measurement and simple referrals.
Not recommended for
• Dirty fluids.
• Low or unstable flow rates.
• Where step changes in viscosity can occur.
• For small bore pipes.
100 mm (4") horizontal or larger.
• Simple installation in large bore pipes.
• Ideal for clean fluids and non-waxing oils.
• Suitable for line viscosity measurement and simple referrals.
• Dirty fluids
• Low or unstable flow rates.
• Where step changes in viscosity can occur.
• for small bore pipes.
• Where temperature effects are significant.
Any.
• Adaptable installation to any diameter main pipe and for tank applications.
• Ideal for flow and temperature conditioning.
• Suitable for complex referrals and for use with heat exchangers.
• Suitable for step changes in viscosity.
• Fast response.
• Ideal for analyser cubicles.
• Uncontrolled flow rates.
• Careful system design required to ensure representative measurement.
• Frequently requires the use of a pump.
Installation (Short Stem) Electrical ConnectionsInstallation (Long Stem)Introduction
(1)
Approval for use in hazardous areas is limited to –40 to +200°C (–40 to +392°F)

2.3.2 Meter orientation

The meter must always be installed horizontally, and orientated to allow flow in the gap between the tines. This is irrespective of the pipe line orientation, and helps to prevent the trapping of bubbles or solids on the meter.
Installation and Configuration Manual 9
Installation (Short Stem)
Bubbles rise!
Solids sink!
the slot must be
vertical
.
For ALL pipe and flow directions
.
the meter
must be
horizontal
Figure 2-1 Meter orientation
Note: All drawings and dimensions given in the following sections are derived from detailed dimensional drawings. They are given here for planning purposes only. Before commencing fabrication, reference should always be made to the current issue of the appropriate drawings ­contact Micro Motion for details.

2.3.3 Free stream installation - flanged fitting

Conditions:
• Flow: 0.3 to 0.5 m/s (at the meter)
• Viscosity: 0.5 to 12,500 cP
• Temperature: -50 °C to 200 °C (–58 °F to 392 °F)
[-40 °C to 200 °C (-40 °F to 392 °F) in hazardous areas]
Note: The thermal mass of the flanges may affect the response time of the meter to temperature changes.
The view shown below is schematic to show the dimensions of the side pocket, which is fabricated by the end user.
10 Micro Motion 7827 Digital Viscosity Meter
Installation (Short Stem)
circlip
4” or larger;
horizontal
6” or larger;
vertical
2.75”
(70 mm ±2 mm)
7.75”
(197 mm)
Free Stream; flanged
2” (52.3 mm)
wall thickness at least
0.15” (3.912 mm)
2” Schedule 40
4.37”
(111 mm)
0.47” (12 mm)
PTFE
ring
circlip
PTFE
ring
circlip
PFA
ring
circlip
Installation (Short Stem) Electrical ConnectionsInstallation (Long Stem)Introduction
The pocket geometry must be consistent with 2" schedule 40 tube in both internal diameter and minimum wall thickness, such as:
• Internal diameter: 2" (52.5 mm)
• Wall thickness: minimum 0.15" (3.912 mm)
Weld neck or slip-on flanges may be used, according to the flange rating selected. However, for higher rated flanges, only slip-on flanges may give the necessary clearances.

2.3.4 Free stream installation - weldolet

This is the preferred option where temperature variations are a critical factor. The reduced thermal mass of the weldolet's taper-lock fitting renders it more able to track rapid changes in temperature.
Conditions:
• Flow: 0.3 to 0.5 m/s (at the meter)
• Viscosity: 0.5 to 12,500 cP
• Temperature: -50 °C to 200 °C (–58 °F to 392 °F)
[-40 °C to 200 °C (-40 °F to 392 °F) in hazardous areas]
The weldolet has a 1.5" taper lock fitting, and is supplied to be welded on 4", 6", 8" or 10" pipelines. Use of the weldolet ensures that the tines of the 7827 meter are orientated correctly and are fully inserted into the fluid stream.
Before fitting the weldolet, the pipeline must be bored through at 2.1" (52.5 mm) diameter to accept the viscometer. The weldolet must be welded to the pipeline concentrically with the pre-bored hole.
The view shown below is a schematic to show the relevant dimensions.
Installation and Configuration Manual 11
Installation (Short Stem)
10” (254 mm)
Horizontal: 4” or larger Vertical: 6” or larger
Weld
4.4” (111 mm)
Free stream weldolet
to suit pipe diameter
(4, 6, 8 or 10” N.B.)
2.1” (52.5 mm)
min
Figure 2-2 Free stream 1.5" Swagelock fitting
The installation will conform generally to Schedule 40 pressure ratings. The weldolet fabrication is rated to 100 Bar at ambient temperature.
Note: Correct installation and pressure testing of the fitting is the responsibility of the user.

2.3.5 T-piece installation

Conditions:
The thermal mass of the flanges may affect the response time of the meter to temperature changes.
Flow velocity at the pipe wall and fluid viscosity must be within the limits shown to ensure that the fluid within the pocket is refreshed in a timely manner. This installation will not respond as rapidly as the free-stream installation to step changes in viscosity.
The view shown is a schematic to show the dimensions of the side pocket, which is fabricated by the end user.
• Flow: 0.5 to 3.0 m/s (at the pipe wall)
• Viscosity: 0.5 to 100 cP
• Temperature: -50 °C to 200 °C (–58 °F to 392 °F)
[-40 °C to 200 °C (-40 °F to 392 °F) in hazardous areas]
12 Micro Motion 7827 Digital Viscosity Meter
Installation (Short Stem)
“T” piece Flanged
D
4” or larger;
horizontal
or vertical
6.9”
(175 mm ±2
mm)
7.75”
(197 mm)
2” (52.3 mm)
wall thickness at least
0.15” (3.912 mm)
2” Schedule 40
PFA
ring
circlip
0.47” (12 mm)
4.37” (111 mm)
Installation (Short Stem) Electrical ConnectionsInstallation (Long Stem)Introduction
The pocket geometry must be consistent with 2" schedule 40 tube in both internal diameter and minimum wall thickness, i.e.:
• Internal diameter: 2.1" (52.5 mm)
• Wall thickness : minimum 0.15" (3.912 mm)
Weld neck or slip-on flanges may be used, according to the flange rating selected. However, for higher rated flanges, only slip-on flanges may give the necessary clearances.

2.3.6 Flow-through chamber installation

Flow-through chambers are fabricated by Micro Motion, and are available with either weld prepared ends or with flange or compression fittings for connection into the process pipe lines. They are available with 1" NB, 2" NB, or 3" NB inlet and outlet pipes.
Note: The length of the inlet and outlet pipes must not be altered, otherwise the temperature response and stability of the fitting may be adversely affected.
Conditions:
• Flow: constant, between 10 and 30 l/min for 2" sch 40 calibration bore section, 5–300 l/min for 3" sch 80 calibration bore.
• Viscosity: 0.5 to 1000 cP
• Temperature: -50 °C to 200 °C (–58 °F to 392 °F)
[-40 °C to 200 °C (-40 °F to 392 °F) in hazardous areas]
Installation and Configuration Manual 13
• Pressure: 70 bar @ 204 °C, subject to process connections.
The PT100 is a direct insertion type, without a thermowell, and uses a ¾" Swagelok connection.
The diagram below shows an example of this type of standard installation.
Installation (Short Stem)
Dimensions shown in inches (mm)
The three compression fittings on the flow pockets (½" drain, ¾" temp probe, and 1-½" mounting nut for the meter) are rated to above the working pressure of the flow pocket. The fittings may be Swagelok or Parker; both are used in manufacture.
The fittings are certified to the following standards:
• Swagelok: SO9001 / 9002, ASME,TUV,CSA,DNV
• Parker: ISO 9001 / 9002, TUV, DNV, LLOYDS

2.4 Installation in the pipeline or system

Viscosity is a highly sensitive indicator of change in a fluid – a key reason why viscosity measurement is increasingly being chosen as a process measurement.
This sensitivity means that the measurement can be very sensitive to extraneous effects and therefore great care must be taken to consider all the factors which affect measurement when assessing the installation requirements.
Like many other meters, the optimum performance of the viscometer depends upon certain conditions of the fluid and configuration of the process pipe-work. By introducing appropriate flow conditioning, the optimum performance of the 7827 meter can be achieved at any chosen location in the process system.
14 Micro Motion 7827 Digital Viscosity Meter
Installation (Short Stem)
You must first select a location which serves the application objective; e.g. installed close to the point of control. Then, consideration can be given to fluid conditioning at that point. Where the application requirements allow a degree of tolerance in the point chosen for installation, the installation may be able to take advantage of natural flow conditioning.
The choice of mechanical installation (free stream, “T” piece or flow-through chamber) will be dictated partly by application needs and partly by the fluid conditions, such as:
• Condition of fluid at the sensor
• Thermal effects
• Flow rate
•Entrained gas
• Solids contamination
Fluid at the sensor
The fluid in the effective zone of the 7827 meter must be of uniform composition and at uniform temperature. It must be representative of the fluid flow as a whole.
This is achieved either by mixing of the fluid either using a static inline mixer or taking advantage of any natural pipe condition that tends to cause mixing, such as pump discharge, partially open valves. The viscometer should be installed downstream where the flow is just returning to laminar flow conditions.
Thermal effects
Avoid temperature gradients in the fluid and in the pipe work and fittings immediately upstream and downstream of the viscometer.
Always insulate the viscometer and surrounding pipework thoroughly. Insulation must be at least 1" (25 mm) of rockwool, preferably 2" (50 mm) (or equivalent insulating heat jacket) and enclosed in a sealed protective casing to prevent moisture ingress, air circulation, and crushing of the insulation. Special insulation jackets are available from Micro Motion for the flow-through chambers, which, because of the low volumetric flow rates and hence low heat flow, are more vulnerable to temperature effects.
Avoid direct heating or cooling of the viscometer and associated pipe work upstream and downstream that is likely to create temperature gradients. If it is necessary to provide protection against cooling due to loss of flow, electrical trace heating may be applied, provided it is thermostatically controlled and the thermostat is set to operate below the minimum operating temperature of the system.
Installation (Short Stem) Electrical ConnectionsInstallation (Long Stem)Introduction
Where flow-through chambers are used and where base (or referred) viscosity is required and the behavior of the fluid is such that the temperature of the sample flow will require controlling, heat exchangers should be fitted upstream a sufficient distance from the chamber so that the fluid temperature is relatively stable. Insulation should be extended from the viscometer to the outlet from the heat exchanger. Fluid heat exchangers should be controlled by modulating the flow rate of the heat exchange fluid and not by modulating the sample flow rate.
Flow rate
Flow rates and velocities should be maintained relatively constant within the limits given. The fluid flow provides a steady heat flow into the viscometer section, and the flow rate influences the self cleaning of the sensor and the dissipation of bubbles and solid contaminants.
Installation and Configuration Manual 15
Installation (Short Stem)
Where it is necessary to install the viscometer in a by-pass (either using the free stream installation in a 4" diameter horizontal by-pass, or a flow-through chamber), flow may be maintained using pressure drop, pitot scoop, or by a sample pump. Where a pump is used, the pump should be upstream of the viscometer.
Entrained gas
Gas pockets can disrupt the measurement. A brief disruption in the signal caused by transient gas pockets can be negated in the signal conditioning software, but more frequent disruptions or serious gas entrainment must be avoided. This can be achieved by observing the following conditions:
• Keep pipe lines fully flooded at all times
• Vent any gas prior to the viscometer
• Avoid sudden pressure drops or temperature changes which may cause dissolved gases to break out of the fluid
• Maintain a back pressure on the system sufficient to prevent gas break out (e.g. back pressure equivalent to twice the ‘head loss’ plus twice the vapor pressure)
• Maintain flow velocity at the sensor within the specified limits.
Solids contamination
• Avoid sudden changes of velocity that may cause sedimentation.
• Install the viscometer far enough downstream from any pipework configuration which may cause centrifuging of solids (e.g. bends).
• Maintain flow velocity at the sensor within the specified limits.
• Use filtration if necessary.
The diagram below illustrates some of the principles outlined in this section. It shows a free-stream viscometer installation with an additional sample take off. The position of both is such that the static mixing (which could be caused by pump discharge or partially closed valve), has negated the adverse effects of bends and established laminar flow, and has ensured that the fluid is thoroughly mixed and thus of uniform composition and temperature. The ideal place for a free stream or “T” piece installation, or for the by-pass take off point is where the flow has just begun to be laminar.
Note: The insulation extends upstream and downstream far enough to prevent conduction losses in the pipe walls from degrading the temperature conditioning of the fluid at the sensor.
16 Micro Motion 7827 Digital Viscosity Meter
Installation (Short Stem)
Installation (Short Stem) Electrical ConnectionsInstallation (Long Stem)Introduction

2.5 Typical installations

The following diagrams illustrate some typical solutions for line viscosity measurement, simple base viscosity referral and base viscosity using temperature control of the sample flow.
In all examples, the fluid flow is assumed to be uniform in composition and temperature as it enters the viscometer section.

2.5.1 Jacketed pipeline

The diagram below shows a jacketed pipeline. The heating fluid in the jacket will cause temperature gradients, and therefore it is discontinued through the viscometer section. If protection against cooling due to loss of flow is required through the unjacketed section then it must be provided using electrical trace heating.
Installation and Configuration Manual 17
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