GE DigitalFlow GS868 User guide

GE
Sensing & Inspection Technologies
DigitalFlow™ GS868
Panametrics Steam Ultrasonic Mass Flowmeter
Startup Guide (1 and 2-Channel)

GE
Sensing & Inspection Technologies
DigitalFlow™ GS868
Panametrics Steam Ultrasonic Mass Flowmeter
Startup Guide (1 and 2-Channel)
910-190UD1
March 2008
The DigitalFlow GS868 is a GE Panametrics product. GE Panametrics has joined other GE high-technology
businesses under a new name—GE Sensing & Inspection Technologies.

iii
March 2008
Warranty Each instrument manufactured by GE Sensing, Inc. is warranted to be
free from defects in material and workmanship. Liability under this
warranty is limited to restoring the instrument to normal operation or
replacing the instrument, at the sole discretion of GE. Fuses and
batteries are specifically excluded from any liability. This warranty is
effective from the date of delivery to the original purchaser. If GE
determines that the equipment was defective, the warranty period is:
•one year for general electronic failures of the instrument
•one year for mechanical failures of the sensor
If GE determines that the equipment was damaged by misuse,
improper installation, the use of unauthorized replacement parts, or
operating conditions outside the guidelines specified by GE, the
repairs are not covered under this warranty.
The warranties set forth herein are exclusive and are in lieu of
all other warranties whether statutory, express or implied
(including warranties of merchantability and fitness for a
particular purpose, and warranties arising from course of
dealing or usage or trade).
Return Policy If a GE Sensing, Inc. instrument malfunctions within the warranty
period, the following procedure must be completed:
1. Notify GE, giving full details of the problem, and provide the model
number and serial number of the instrument. If the nature of the
problem indicates the need for factory service, GE will issue a
RETURN AUTHORIZATION number (RA), and shipping instructions
for the return of the instrument to a service center will be
provided.
2. If GE instructs you to send your instrument to a service center, it
must be shipped prepaid to the authorized repair station indicated
in the shipping instructions.
3. Upon receipt, GE will evaluate the instrument to determine the
cause of the malfunction.
Then, one of the following courses of action will then be taken:
•If the damage is covered under the terms of the warranty, the
instrument will be repaired at no cost to the owner and returned.
•If GE determines that the damage is not covered under the terms
of the warranty, or if the warranty has expired, an estimate for the
cost of the repairs at standard rates will be provided. Upon receipt
of the owner’s approval to proceed, the instrument will be repaired
and returned.

v
March 2008
Table of Contents
Chapter 1: Installation
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Unpacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Site Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Electronics Console Location. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Flowcell Location. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Transducer Location. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Cable Lengths. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Temperature and Pressure Transmitters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Transducer Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Installing a Flowcell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Installing Temperature and Pressure Transmitters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Mounting the GS868 Electronic Console . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Making the Electrical Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Wiring the Line Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Wiring the Transducers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
Wiring the 0/4-20 mA Analog Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-10
Wiring the Serial Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-10
Wiring an Alarms Option Card. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-14
Wiring a 0/4-20 mA Analog Inputs Option Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
Wiring a Totalizer/Frequency Outputs Option Card. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-16
Wiring an RTD Inputs Option Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-17
Wiring a 0/4-20 mA Analog Outputs Option Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-17
Chapter 2: Initial Setup
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Navigating Through the User Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Accessing the User Program. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Activating a Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
1-Channel Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2-Channel Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
1 and 2-Channel Meters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Entering System Data for a Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
A 1-Channel Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
A 2-Channel Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
1 and 2-Channel Meters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Entering Pipe Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Transducer Number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Pipe OD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Pipe Wall. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Path Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Axial Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Fluid Type. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Reynolds Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Calibration Factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8

March 2008
vi
Table of Contents (cont.)
Chapter 3: Operation
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Powering Up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Using the Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Taking Measurements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Foundation Fieldbus Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
Chapter 4: Specifications
General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Operational. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Transducer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Flowcell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
Appendix A: CE Mark Compliance
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
External Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
Appendix B: Data Records
Option Cards Installed. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
Initial Setup Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2
Appendix C: Optional Enclosures
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
Rack Mount Enclosure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
Rack Mount Wiring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
Rack Mount Front Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-2
Appendix D: Measuring P and L Dimensions
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-1
Measuring P and L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-1

Chapter 1

Installation
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Unpacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Site Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Installing a Flowcell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Installing Temperature and Pressure Transmitters . . . . . . . . . . . . . . . . . 1-5
Mounting the GS868 Electronic Console . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Making the Electrical Connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

Installation 1-1
March 2008
Introduction To ensure safe and reliable operation of the Model GS868 Steam
Ultrasonic Mass Flowmeter, the system must be installed in
accordance with the guidelines established by GE’s engineers. Those
guidelines, which are explained in detail in this chapter, include the
following specific topics:
•Unpacking the Model GS868 system
•Selecting a suitable site for the electronics console and the
flowcell/transducers
•Installing a flowcell
•Installing temperature and pressure transmitters
•Installing the Electronics Console
•Wiring the Electronics Console.
!WARNING!
The Model GS868 flowmeter can measure the flow rate of
many gases, some of which are potentially hazardous. In
such cases, the importance of proper safety practices
cannot be overemphasized.
Be sure to follow all applicable local safety codes and
regulations for installing electrical equipment and working
with hazardous gases or flow conditions. Consult company
safety personnel or local safety authorities to verify the
safety of any procedure or practice.
ATTENTION EUROPEAN CUSTOMERS!
To meet CE Mark requirements, all cables must be installed
as described in Appendix A, CE Mark Compliance.
Unpacking Carefully remove the electronics console, the transducers, and the
cables from the shipping containers. Before discarding any of the
packing materials, account for all components and documentation
listed on the packing slip. The discarding of an important item along
with the packing materials is all too common. If anything is missing
or damaged, contact the factory immediately for assistance.

March 2008
1-2 Installation
Site Considerations Because the relative physical locations of the flowcell and the Model
GS868 electronics console are important, use the guidelines given in
this section to plan the Model GS868 system installation.
Electronics Console
Location The standard Model GS868 electronics enclosure is a Type-4X
weather-resistant, dust-tight, indoor/outdoor type. Typically, the
electronics console is mounted in a meter shed. When choosing a
mounting site, make sure that the location permits easy access to the
console for programming, testing, and servicing.
Note: For compliance with the European Union’s Low Voltage
Directive (73/23/EEC), this unit requires an external power
disconnect device such as a switch or circuit breaker. The
disconnect device must be marked as such, clearly visible,
directly accessible, and located within 1.8 m (6 ft) of the
Model GS868.
Flowcell Location The pipeline flowcell consists of the flowmeter transducers and any
pressure and/or temperature transducers employed as part of the
flowmeter system. Ideally, choose a section of pipe with unlimited
access as the flowcell; for example, a long stretch of pipe that is
above ground. However, if the flowcell is mounted on an
underground pipe, dig a pit around the pipe to facilitate installation of
the transducer mechanisms.
Transducer Location For a given fluid and pipe, the Model GS868’s accuracy depends
primarily on the location and alignment of the transducers. In addition
to accessibility, when planning for transducer location, adhere to the
following guidelines:
1. Locate the transducers so that there are at least 20 pipe diameters
of straight, undisturbed flow upstream and 10 pipe diameters of
straight, undisturbed flow downstream from the measurement
point. To ensure undisturbed flow, avoid: sources of turbulence in
the fluid such as valves, flanges, expansions and elbows; swirl;
and dips or low spots in which condensed liquid may collect.
2. Because condensate or sediment at the bottom of the pipe may
cause attenuation of the ultrasonic signal, locate the transducers on
the side of a horizontal pipe, where possible. If limited pipe access
necessitates top-mounted transducers and the sound beam path
includes a reflection, shift the transducers to at least 10°off top
center. This will minimize the influence of any sediment on the
reflected ultrasonic signals.

Installation 1-3
March 2008
Cable Lengths Locate the flowcell/transducers as close as possible to the electronics
console. The factory supplies transducer cables up to 500 ft (153 m)
in length. If longer cables are required, consult the factory for
assistance.
Temperature and Pressure
Transmitters When installing temperature and/or pressure transmitters in the
flowcell, locate them downstream of the flowmeter transducers.
These transmitters should be positioned no closer to the flowmeter
transducers than 2 pipe diameters and no further away from the
flowmeter transducers than 20 pipe diameters.
Transducer Cables When installing the transducer cables, always observe established
standard practices for the installation of electrical cables. Specifically,
do not route transducer cables alongside high amperage AC power
lines or any other cables that could cause electrical interference. Also,
protect the transducer cables and connections from the weather and
corrosive atmospheres.
Note: When using non-GE cables to connect the flowmeter
transducers to the Model GS868 electronics console, the
cables must have electrical characteristics identical to the GE
cables. Type RG 62 a/u coaxial cable should be used, and
each cable must be the same length (within ±4 in.).
Installing a Flowcell A flowcell is the section of pipe where the transducers are mounted. It
can be created either by mounting the transducers on the existing
pipeline or by mounting them on a spoolpiece. A spoolpiece is a
separately manufactured pipe section, matched to the existing pipe,
which contains ports for mounting the transducers. This approach
allows the transducers to be aligned and calibrated before inserting
the spoolpiece into the pipeline.
Figure 1-1 on page 1-4 shows a block diagram of a typical Model
GS868 system, including optional pressure and temperature
transmitters. For detailed instructions on installing the transducers
and/or spoolpiece, refer to the supplied drawings and the GE Gas
Transducer Installation Guide for Ultrasonic Flowmeters.

March 2008
1-4 Installation
Figure 1-1: A Typical Model GS868 System
Transducer
Flowcell
Temperature Transmitter
Pressure Transmitter
Preamp
Transducer
Electronics Console
STEAM
FLOW

Installation 1-5
March 2008
Installing Temperature
and Pressure
Transmitters
Optional temperature and pressure transmitters may be installed as
part of the flowcell, near the ultrasonic transducer ports. Be sure to
observe the siting requirements given earlier in this chapter. These
transmitters must use a 0/4-20 mA signal to transmit the temperature
and pressure values to the Model GS868 electronics console. In turn,
the electronics console will provide a 24 VDC signal to power the
transmitters. Any desired transmitters or sensors may be used, but
they must have an accuracy equal to 0.5% of the reading or better.
Note: Resistive Thermal Devices (RTDs) are a good choice for
measuring the temperature.
Typically, a 1/2” or 3/4” NPT female threaded port is used to mount
the transmitters on the flowcell. If the pipeline is insulated, the
coupling may need to be extended to provide convenient access. Of
course, other types of mounting ports, including flanged ports, may
be used for the transmitters.
IMPORTANT: Under changing temperature and pressure
conditions, the Model GS868 can calculate accurate
steam density and mass flow only if temperature and
pressure transmitters have been installed.
Figure 1-2 below shows a typical mounting arrangement for the
pressure and temperature transmitters. The temperature sensor should
protrude 1/4 to 1/2 way into the pipe.
Figure 1-2: Typical Temperature/Pressure Transmitter Mounting
Temperature Transmitter
Pressure Transmitter
Isolation Valve
Flowcell Wall
Coupling
Thermowell
RTD

March 2008
1-6 Installation
Mounting the GS868
Electronic Console The standard model GS868 electronics package is housed in a Type-
4X weather-resistant enclosure. Refer to Figure 1-9 on page 1-19 for
the mounting dimensions of this enclosure.
IMPORTANT: For meters supplied in one of the optional enclosure
styles, refer to Appendix C, Optional Enclosures, for
specific mounting dimensions and instructions.
!WARNING!
Proper grounding of the GS868 chassis is required to
prevent the possibility of electric shock. See Figure 1-10 on
page 1-20 to locate the internal ground connection.
Making the Electrical
Connections
ATTENTION EUROPEAN CUSTOMERS!
To meet CE Mark requirements, all cables must be installed
as described in Appendix A, CE Mark Compliance.
This section contains instructions for making all the necessary
electrical connections to the Model GS868 flowmeter. Refer to
Figure 1-10 on page 1-20 for a complete wiring diagram of the unit.
IMPORTANT: For meters supplied in one of the optional enclosure
styles, refer to Appendix C, Optional Enclosures, for
the appropriate wiring diagram and specific wiring
instructions.
Except for the power connector, all electrical connectors are stored in
their terminal blocks during shipment and may be removed from the
enclosure for more convenient wiring. Feed the cables through the
conduit holes on the bottom of the enclosure, attach the wires to the
appropriate connectors and plug the connectors back into their
terminal blocks.
Note: For compliance with the European Union’s Low Voltage
Directive (73/23/EEC), a transparent plastic shroud protects
the electrical connections. The shroud must remain in place,
except while wiring the unit. Reinstall the shroud after the
wiring has been completed.
Once the Model GS868 is completely wired, proceed to Chapter 2,
Initial Setup, to configure the unit for operation.

Installation 1-7
March 2008
Wiring the Line Power ATTENTION EUROPEAN CUSTOMERS!
To meet CE Mark requirements, all cables must be installed
as described in Appendix A, CE Mark Compliance.
The Model GS868 may be ordered for operation with power inputs of
100-120 VAC, 220-240 VAC, or 12-28 VDC. The label on the shroud
inside the electronics enclosure, just above the TB1 line power
terminal block, lists the required line voltage and the fuse rating for
the unit (the fuse rating is also listed in Chapter 4, Specifications). Be
sure to connect the meter only to the specified line voltage.
Note: For compliance with the European Union’s Low Voltage
Directive (73/23/EEC), this unit requires an external power
disconnect device such as a switch or circuit breaker. The
disconnect device must be marked as such, clearly visible,
directly accessible, and located within 1.8 m (6 ft) of the
Model GS868.
Refer to Figure 1-3 on page 1-8 or Figure 1-10 on page 1-20 to locate
terminal block TB1 and connect the line power as follows:
!WARNING!
Improper connection of the line power leads or connecting
the meter to the incorrect line voltage will damage the
unit. It will also result in hazardous voltages at the flowcell
and associated piping and within the electronics console.

March 2008
1-8 Installation
Wiring the Line Power
(cont.)
1. Remove the plastic shroud that covers the terminal blocks. Be sure
to reinstall the shroud after all of the wiring has been completed.
2. Strip ¼” of insulation from the end of the power and neutral or line
leads (or the positive and negative DC power leads), and ½” from
the end of the ground lead.
3. Connect the ground lead to the internal ground connection located
on the side panel of the inclosure (see Figure 1-3 below).
IMPORTANT: The incoming ground lead must be connected to the
internal ground connection.
4. Connect the neutral or line lead (or the negative – DC power lead)
to TB1-2 and the line power lead (or the positive + DC power lead)
to TB1-3 as shown in Figure 1-3 below.
IMPORTANT: Do not remove the existing PC board ground wire or
the cover ground wire.
Figure 1-3: Wiring the Line Power
1
TB1
N/L2
Ground
23
L1G
Internal
Ground
Connection
PC Board
Ground Wire
Cover
Ground Wire
G – + AC DC
AC Line Power
or DC +
AC Neutral/Line
or DC –

Installation 1-9
March 2008
Wiring the Transducers ATTENTION EUROPEAN CUSTOMERS!
To meet CE Mark requirements, all cables must be installed
as described in Appendix A, CE Mark Compliance.
Wiring a typical Model GS868 ultrasonic natural gas flowmeter
system requires interconnection of the following components:
•a pair of transducers (per channel) mounted in the flowcell
•a preamplifier for each channel
•a lightning protector (optional)
•the electronics console
To wire the transducers, complete the following steps:
!WARNING!
Before connecting the transducers, take them to a safe
area and discharge any static buildup by shorting the
center conductor of the transducer cables to the metal
shield on the cable connector.
1. Using the pair of coaxial cables with BNC to BNC connectors
supplied by the factory (or equivalent cables), connect both
transducers to the preamplifier.
Caution!
As part of maintaining the FM/CSA environmental rating
(NEMA/TYPE 4) on the remote preamplifier, thread sealant
is required on all conduit entries.
2. If an optional lightning protector is being installed, connect it to
the preamplifier.
3. Using the pair of coaxial cables with BNC to flying lead
connectors supplied by the factory (or equivalent cables), connect
the preamplifier to terminal block CH1 in the electronics console.
Refer to Figure 1-10 on page 1-20 for the location of the terminal
block and the terminal block pin assignments.
4. For a 2-channel Model GS868 flowmeter, repeat steps 1-3 to wire
the Channel 2 transducer system to terminal block CH2.
Note: It is not required that Channel 2 of a 2-channel Model GS868
be used. This channel may be left inactive for future use.
After the wiring has been completed, the transducer channel(s) must
be activated before measurements can begin. See Chapter 2, Initial
Setup, for instructions.

March 2008
1-10 Installation
Wiring the 0/4-20 mA
Analog Outputs The standard configuration of the Model GS868 flowmeter includes
two isolated 0/4-20 mA analog outputs (designated as A and B).
Connections to these outputs may be made with standard twisted-pair
wiring. The current loop impedance for these circuits must not exceed
550 ohms.
Refer to Figure 1-10 on page 1-20 for the location of terminal block
I/O and wire the terminal block as shown.
Wiring the Serial Port The Model GS868 is equipped with a built-in serial communications
port. The standard port is an RS232 interface, but an optional RS485
interface is available upon request. Proceed to the appropriate sub-
section for wiring instructions. For more information on serial
communications, refer to the EIA-RS Serial Communications Manual
(916-054).
Wiring the RS232 Interface The RS232 communications port provides a serial interface for
connecting the Model GS868 flowmeter to a printer, an ANSI
terminal or a personal computer.
The RS232 serial interface is wired as Data Terminal Equipment
(DTE), and the signals available at the Model GS868 RS232 terminal
block are shown in Table 1-1 below. Refer to Figure 1-8 on page 1-16
to locate terminal block RS232 and complete the following steps to
wire the terminal:
1. Use the information in Table 1-1 below to construct a suitable
cable for connecting the Model GS868 to the external device. If
desired, an appropriate cable may be purchased from GE.
2. Wire the flying leads end of the cable to terminal block RS232 and
connect the other end of the cable to the printer, ANSI terminal or
personal computer.
After the wiring has been completed, consult the User’s Manual for
the external device to configure it for use with the Model GS868.
Table 1-1: RS232 Connection to DCE or DTE Device
RS232
Pin # Signal Description
DCE
DB25
Pin #
DTE
DB25
Pin #
DTE
DB9
Pin #
1 RTN (Return) 7 7 5
2 TX (Transmit) 3 2 3
3 RX (Receive) 2 3 2
4DTR (Data Terminal Ready) 20 20 4
5CTS(CleartoSend)458

Installation 1-11
March 2008
Wiring the RS485 Interface Use the optional RS485 serial port to network multiple GS868
flowmeters to a single computer terminal. Upon request, the standard
RS232 port on the GS868 may be configured as a two-wire, half-
duplex RS485 interface, through a device such as the INMAC Model
800052 RS232-RS422/RS485 converter.
To wire the RS485 serial port, refer to Figure 1-10 on page 1-20 and
complete the following steps:
1. Disconnect the main power to the unit and remove the cover.
2. Install the required cable clamp in the chosen conduit hole on the
side of the electronics enclosure.
3. Feed one end of the cable through the conduit hole, wire it to
terminal block J1 and secure the cable clamp. Connect the other
end of the cable to the converter, as shown in Figure 1-4 below.
Figure 1-4: Typical RS485 Connections
!ATTENTION EUROPEAN CUSTOMERS!
To meet CE Mark requirements, all cables must be installed
as described in Appendix A, CE Mark Compliance.
4. If wiring of the unit has been completed, reinstall the rear cover on
the enclosure and tighten the set screw.
NC 6
NC 7
RX 8
TX 9
1 TD OUT
2
3
4 RD IN
GS868 Converter

March 2008
1-12 Installation
Wiring the Ethernet
Interface
A modified GS868 can use the Ethernet interface to communicate to
an internal network. An optional Ethernet card with a unique MAC
(IP) address (installed only in slots 5 or 6) includes an RJ45
connector. To connect the Ethernet-enabled GS868 to the network,
insert the jack of an RJ45 cable into the RJ45 connector, route the
cable through the bottom of the GS868, and wire the other end of the
cable to the Ethernet network according to the manufacturer’s
instructions. An external connection is required between the Ethernet
option card and the GS868’s RS232 connector, as shown in Table 1-2
below.
Note: The MAC address for a specific GS868 is included with
customer documentation. For more information on setting up
the MAC address, refer to Chapter 6 of the Programming
Manual.
Wiring the MODBUS/TCP
Interface
Customers can also use a modified GS868 that provides a MODBUS/
TCP interface to communicate to an internal network. An optional
MODBUS/TCP card with a unique MAC (IP) address (installed only
in slots 5 or 6) includes an RJ45 connector. To connect the
MODBUS/TCP-enabled GS868 to the network, insert the jack of an
RJ45 cable into the RJ45 connector, route the cable through the
bottom of the GS868, and wire the other end of the cable to the
Ethernet network according to the manufacturer’s instructions.
Note: The MAC address for a specific GS868 is included with
customer documentation. For more information on setting up
the MAC address, refer to Chapter 6 of the Programming
Manual.
Table 1-2: RS232 to Ethernet Interconnections
GS868 Type Terminal Block Terminal Block
Wall Mount
RS232 on Main Board TB1 on Ethernet Card
TX Pin 1
RX Pin 2
RTN Pin 3
Rack Mount
RS232 on Main Board TB2 on Ethernet Card
TX Pin 1
RX Pin 2
RTN Pin 3

Installation 1-13
March 2008
Wiring the Foundation
Fieldbus Network
Fieldbus network connections are made at J8/J9, pins 1 and 2 (see
Figure 1-5 below). Optionally, a shield can be connected to J8/J9
pin 3, depending on the network wiring. Connector J8 or J9 will be
installed depending on the option ordered by the customer.
No connections are made to J8/J9, pins 7 and 9, under normal
operation. If it is desired to reset the network board to factory
defaults:
1. Connect a jumper between J8/J9 pin 7 and pin 9.
2. Power cycle the instrument.
3. Ten seconds after the power has been restored to the unit, remove
the jumper to return the network board to normal operation.
Figure 1-5: Network Connections - Standard Option Interior
1
9
J8
1
9J9