EXPERIMENT 4
TESTING DIAPHRAGM METER WITH A TRANSFER PROVER
OBJECTIVE
The purpose of this experiment was to test the accuracy of the diaphragm meter using the
transfer prover.
EQUIPMENT
Transfer Prover is a portable proving system designed to provide accurate field proving for rotary,
turbine, and diaphragm meters. The system as illustrated in Figure 1, consists of a Master Meter,
a RTU, and a Blower. The gas, or air, is pulled by the blower and passed through the field meter
(meter under calibration or test) before passing through the master meter. The master meter is
calibrated for a certain range of the flow rate. This range allows to cover testing for a range of
diaphragm meters, such as the one tested in this lab. The closer the flowrate is to the capacity of
the meter being tested, the higher the accuracy will be from the readings.
FIGURE 1. Transfer Prover Components
The major components are described below.
Master Meter
This device determines air flowrate and display it on the RTO screen. It is equipped with a
temperature probe and continuously updates the flow rate in real time as the blower is adjusted.
Figure 2 shows the Master Meter when it is installed on the meter run.
RTU with Keypad Interface
This is the digital controller. It is used at the start to setup the parameters of the experiment. by
using the arrow keys. The escape key can be used at any time to abort the test. It is also designed
to connect to a laptop. The test volume and flowrate can be observed continuously while the
system is in use. Figure 2 shows the Keypad Interface as it is installed on the diaphragm meter.
FIGURE 2. MASTER METER INSTALLED ON THE METER RUN
FIGURE 3. KEYPAD INTERFACE INSTALLED ON THE DIAPHRAGM METER
Blower
This device is an electric pump that moves the air through the system. The flowrate can be
adjusted by moving the lever on the side and can be observed on the digital display. Figure 4
illustrate the blower when it is installed on the outlet of the meter run.
THEORY
In the typical transfer testing system, air or gas passes through the meter under test (field meter)
and the prover’s Master Meter (MM). Atmospheric air is drawn through the field meter (FM) and
prover by the blower system. Temperature and pressure differences are measured to enable
correction of the data to a common base of comparison. The equations are used to determine:
MM Flow Rate
100%
FM Flow Rate
MM Press. Diff
Press. Corr.,%
100%
FM Press. Diff
Uncorr. Proof, %
R
Temp. Corr., %
MM Temp. R
FM Temp.
o
o
Corr. Proof, % Uncorr. Proof
100%
100 Press. Corr. 100 Temp. Corr.
100
100
PROCEDURE
The step-by-step procedure to set up and perform a test are available in the manual. The
followings steps provide a brief description of the experiment.
1)
Remove the index or chart on the output drive of the field meter (FM).
2)
Connect the Master Meter (MM) on the upstream side.
3)
Connect the blower on the downstream side.
4)
Connect the valve to the blower.
5)
Place the RTU on the field meter.
6)
Insert the pressure/temperature connector into the field meter.
7)
Connect the Master Meter to the RTU.
8)
Connect temperature probe to the RTU.
9)
Start the test by opening the valve to allow the air to move through the pipe.
10)
Differential pressures, temperatures, and the flow rate from the meter and the
prover are recorded.
11)
Repeated the previous steps for different flow rates.
RESULTS
Test #
1
2
3
Test
Volume
ft3
10
40
100
Diff. Press
In. Water
MM
0.1
0.3
1.0
FM
0.1
0.4
1.2
Temp
oF
MM FM
71.3 73.7
71.6 73.7
73.3 73.9
Flow Rate
ft3/hr.
MM
308
793
1544
FM
360
830
1540
EXPERIMET #4
Objective:
The objective of this experiment is to test the Transfer Prover, which is a portable
proving system that provides an accurate proving with less effort. The convenient design of the
prover makes it easier to be moved from location to another. The experience was to operate and
check the accuracy of the system in field.
Equipment:
Master Meter (Inlet)
Meter Under Test
Blower (outlet)
Block Valve
Block Valve
Bypass
Valve
Theory:
The transfer prover is a proving system that is portable so it can be used in the field and
for easier use. It is designed to check the accuracy of rotary, turbine and diaphragm meters. It
doesn’t need lots of things such as a vehicle to take it to the field and that is for its compact
design. Another good thing about it is that it only needs AC/DC inverter.
Procedures:
At the beginning the orifice meter needed to be checked for leakage. In order to do that,
valves 1 and 2 kept closed. The change in pressure indicates the presence of leakage in the meter.
To fix that valves 3 and 4 needed to be opened. Then, to make the staticpressure pen to drop to
zero, valve 5 was opened. After that, valve 5 was closed and valves 1 and 2 were opened while
valves 3 and 4 were closed. Finally, valve 5 was reopened again to make the meter ready for the
test and the preliminary checks are done.
The second step was to conduct the test. The flaw rate was set three times. The first was
set at 300
𝑓𝑡 3⁄
𝑓𝑡 3⁄
𝑓𝑡 3⁄
,
the
second
was
at
800
,
and
the
third
was
at
1500
ℎ𝑜𝑢𝑟
ℎ𝑜𝑢𝑟
ℎ𝑜𝑢𝑟 .
The results shows the statics pressure, differential pressure, and the temperature.
Results:
Flow Rate
[ft^3/hr.]
300
800
1500
Diff Press
MM Temp
Fm Temp
0.1
0.4
1.2
72.1
72.2
72.5
74
74.1
74.1
Proof
[%]
98.12
99.77
99.74
Acracy
[%]
101.88
100.23
100.26
q Vs. % Proof
Proof [%]
1
2
3
Test Volume
[ft^3]
10
40
100
100
99.8
99.6
99.4
99.2
99
98.8
98.6
98.4
98.2
98
0
300
600
900
1200
1500
1800
1200
1500
1800
q [ft^3/hr]
Figure 1 q Vs. % Proof
q Vs. % Accuracy
Accuracy [%]
Test
102
101.8
101.6
101.4
101.2
101
100.8
100.6
100.4
100.2
100
0
300
600
900
q [ft^3/hr]
Figure 2 q Vs. % Accuracy
Error
[%]
1.88
0.23
0.26
Error [%]
q Vs. % Error
2
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
0
300
600
900
1200
1500
1800
q [ft^3/hr]
Figure 3 q Vs. % Accuracy
Discussion:
By adjusting the pressure and temperature, the digital gate box device is monitored to
observe the gas flow rate. According to the results above, the lower values of pressure and
temperature correlation, the higher the percent accuracy. In addition, the experiment shows that
there was no occurring leakage while performing the experiment, which is a good indication that
it was successful. After plotting percentage proof, accuracy and error against the flow, the
percentage proof shows an increase as the flow increases. This illustrates the quality performance
of XARTU-Transfer Prover as opposed to the limited capacity bell provers. On the other hand,
the other two plots, the percent accuracy and error, shows a decrease in the percentage as the
flow rate increases.
Reference:
-
https://eagleresearchcorp.com/Resources/Manuals/TransferProverManual.pdf
-
https://asgmt.com/wp-content/uploads/2016/02/011_.pdf
-
https://www.emerson.com/en-us/automation/measurement-instrumentation/flowmeasurement/about-prover-systems
Transfer Prover Operation
Introduction
The Transfer Prover is a portable proving system designed to provide accurate field proving for
rotary, turbine, and diaphragm meters. The compact design allows the prover to be transported to
field locations without the need of a dedicated vehicle or multi-person work crews. The prover
system’s low power design allows testing and blower operation using a standard AC/DC inverter as
opposed to the need for a dedicated AC circuit or gas generator.
Materials/Tools Needed
Pipe Wrenches
Small Crescent Wrench
Screw Driver
Allen Wrenches
Assembly Steps:
Prepare the site.
The prover uses air to measure the meter under test. Therefore the run must be shut in or placed in
bypass mode before starting this test. The index or chart on the output drive of the meter under test
must be removed. The inlet and outlet sides of the run must be identified, and the proper
connectors installed for either an upstream or a downstream test.
Page 4
XARTU/TP™ Transfer Prover Manual
®
Copyright© 2014 Eagle Research Corporation
Page | 4
Standard Meter Piping Configuration
Upstream Configuration
Use the camlock fitting provided for quick and easy connection of the Master Meter on the upstream
side. Install the male camlock fitting for quick connection of the valve and hose assembly on the
downstream side. Use the quarter-turn connector to connect the hose assembly to the blower.
Make sure the ball valve is turned OFF prior to turning on the blower.
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Copyright© 2014 Eagle Research Corporation®
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Upstream Test Configuration
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Downstream Configuration (w/optional remote mount)
Use the female camlock fitting provided to connect the hose assembly with the remote mount kit.
Insert the male connector provided into the outlet side of the Master Meter. Set the Master Meter
onto the supplied tripod. Connect the remote hose assembly to the camlock on the inlet side of the
Master Meter. Connect the valve/hose assembly to the bottom of the tripod, and the quarter-turn
connector to the blower. Make sure the ball valve is turned OFF prior to turning on the blower.
Downstream Test Configuration
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Electronics
Place the gate box on the Meter Under Test. Insert the temperature/pressure quick connector into
the Inlet side of the field meter. Use the blue cable to connect the Master Meter to the RTU. Insert
the temperature probe into the ferruled connector until its fast response tip is in the center of the
inlet. Connect the temperature probe to the RTU. Connect the quick connector pressure tubing
between the temperature/pressure quick connector and the RTU. Connect the gate box to the RTU
with the white connector. When it is convenient to leave the gate box connected to the RTU, use the
short white cable. A longer cable is provided for times when it is not possible or convenient to leave
the two connected.
Connecting the Electronics
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Copyright© 2014 Eagle Research Corporation®
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Running the Test
RTU Interface
The following section discusses the keypad interface to the Transfer Prover. These menu options can
be accessed using the keypad attached to the front of the enclosure or through Field Manager’s™
Virtual Keypad. Note that the keypad strokes denoted in the following text are enclosed in
brackets. Those brackets are not on the keypad.
There are multiple selection screens at the beginning that enable the user to specify setup options
that may change from site to site. In general, these screens have a header in all capital letters on
the top line and a list of options on the remaining three lines. A left arrow points to which option is
selected. This selection can be changed using the arrows on the keypad. Pressing saves the
selection and advances the display to the next selection menu. At any point the user can abort a
setup by pressing . Doing so will cause the display to return to the first selection screen. The
transfer prover remembers the selections made for the previous proof and uses these values as the
default selection next time the selection screens are accessed.
Baud Rate Screen
At any point during the selection menu, the Transfer Prover can be connected to a laptop using Field
Manager™. When first connected, the Transfer Prover display will show the baud rate. This tells the
operator which baud rate to select in Field Manager™.
Once the baud rate has been noted, press to return to the beginning of the selection screens.
Pressing other buttons at this point may cause the Transfer Prover to inadvertently advance to the
next selection screen.
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Selection Mode
The first selection screen allows the user to choose between starting a proof and performing a self
test on the prover. At any point during the option selection process or during the proving process,
pressing will return the program to this screen.
Start Proof begins the process of configuring a proof test. The next selection screen will be ENTER
OPERATOR NAME.
Self Test will put the Transfer Prover in a mode that tests its internal components against a specific
flow rate. Skip ahead to the section entitled Self Test for more information.
Start Proof Mode
Enter Operator Name
This selection screen can be disabled by Field Manager™. If it does not appear on the Transfer
Prover display skip ahead to the next selection screen description.
With this selection screen, a user can enter their name as the operator which will be stored in
history in conjunction with the setup and results of each test. This entry will appear on the summary
report generated by Field Manager.
The string can be up to 16 alphanumeric characters long. To enter an identifier, the keypad must
be used in a manner similar to texting with a cell phone. The following describes each key’s function.
Most of the keys have multiple items listed, press the key multiple times within two seconds to
produce the desired symbol. For instance, pressing three times consecutively with no more
than two seconds between each key press will result in a & being displayed on the screen. If two
consecutive desired symbols are on the same key, a two second delay must be observed after the
first character is on the screen before continuing to the second.
XARTU/TP™ Transfer Prover Manual
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produces #, -, &, “, period, etc.
produces a, b, c, 2
produces d, e, f, 3
produces g, h, i, 4
produces j, k, l, 5
produces m, n, o, 6
produces p, q, r, s, 7
produces t, u, v, 8
produces w, x, y, z, 9
produces space, 0
switches between ‘Abc’, ‘ABC’, ‘123’, and ‘abc’ modes as indicated on the fourth line
of the display. ‘Abc’ capitalizes the first symbol and leaves the remaining symbols lower case.
‘ABC’ capitalizes all symbols. ‘123’ turns the keypad into a strictly numbers pad. ‘abc’ prints
all symbols in lower case. Note: on older models and Field Manager™ Virtual Keypad this key
is denoted .
moves the cursor to the left one space and then clears the current symbol. If
the cursor is in the middle of the entry, all symbols to the right of the cursor will be shifted left
by one position.
moves the cursor one position to the left.
moves the cursor one position to the right.
saves the entry as the Meter ID and advances to the next selection screen.
aborts the entry and returns to the SELECT MODE selection screen.
One other notable function provided by this text entering function is Insert. To insert, simple move
the cursor to the place a symbol addition is needed, and then enter the symbol regularly.
Example 1
Pressing puts the display in number only mode.
Then pressing , , , , , will produce the following.
Example 2
Pressing , , , , , , , , , , , , , will
produce the following when in Abc mode.
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Enter Meter ID
This selection screen can be disabled by Field Manager™. If it does not appear on the Transfer
Prover display skip ahead to the next selection screen description.
With this selection screen, a user can enter a meter identification number that will be stored in
history in conjunction with the setup and results of each test. When the proof history is polled from
the Transfer Prover™, each record can easily be recognized. This entry is the only value displayed
with the date and time of the proof in the report generator. Without this value it can be difficult to
distinguish each proof.
This screen behaves exactly as the selection screen titled ENTER OPERATOR NAME.
Enter Meter Name
This selection screen can be disabled by Field Manager™. If it does not appear on the Transfer
Prover display skip ahead to the next selection screen description.
This selection screen provides a second description string for a given site. It behaves exactly as the
selection screen titled ENTER OPERATOR NAME.
Once finished with this screen, press to proceed to the next selection screen.
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Master Meter
Each Eagle Research® Transfer Prover can be configured to support multiple master meters. This
selection screen is used to specify which master meter is connected to the Transfer Prover for the
current proof. When entering calibration data, it is important to also enter the master meter serial
number. This number will appear below the master meter designator. The operator must verify that
the electronics box is pared with the proper master meter each time the test is preformed. Choose
the appropriate option, and then press to go to the next selection screen.
If the Transfer Prover is only configured for one master meter, this screen will appear for a brief
period and then automatically advance to the next screen.
Input Option
The Transfer Prover comes with a gate box and a push button switch. The gate box is mounted on
top of the meter under test’s output drive in the same fashion as an Eagle Corrector.
The push button option is used when no output drive is available.
Choose the input option used for the current test, and then press to advance to the next
selection screen.
Temp Comp Meter
If the meter under test has a temperature compensated index drive, select yes.
Otherwise, select no.
Select the proper option, and then press to go to the next selection screen.
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Output Drive
This selection screen allows the user to specify the output drive of the meter under test. The
optional values that appear in the screen can be picked in Field Manager™. A different set of
optional values can be specified for each master meter.
This value is in cubic feet per revolution.
After picking the appropriate option, press to go to the next selection screen.
Master Location
This selection screen can be disabled by Field Manager™. If it does not appear on the Transfer
Prover display skip ahead to the next selection screen description.
With the Eagle Research® Transfer Prover, the master can be placed upstream or downstream of the
meter under test. When using pressure compensation, this option is very important as it determines
which meter should show a higher uncorrected volume.
If the master meter is always located in the same position with respect to the meter under test, this
value can be universally specified and this selection screen disabled.
Once the correct location is selected, press to advance to the next selection screen.
XARTU/TP™ Transfer Prover Manual
Copyright© 2014 Eagle Research Corporation®
Page | 14
Leak Detect
This selection screen can be disabled by Field Manager™. If it does not appear on the Transfer
Prover display skip ahead to the next selection screen description.
Selecting Skip will simply advance to the Active screen. Choosing Start will lead to the following
screen.
To understand the ideas behind the leak detection feature and how to arrange the hardware of the
Transfer Prover to perform leak detection, see the section entitled “Testing Setup for Leaks”.
Once satisfied that no significant leaks are present, press to advance to the next screen.
Summary Screens
Validation Type
This selection screen can be disabled by Field Manager™. If it does not appear on the Transfer
Prover™ display skip ahead to the next selection screen description.
With this selection screen, a user can select if the meter was tested the way it was found or after any
changes, how it was left. This will be stored in history in conjunction with the setup and results of
each test. When the proof history is polled from the Transfer Prover, each record will state if it was
an as found test or as left test.
Once the validation type is selected, press to advance to the next selection screen.
XARTU/TP™ Transfer Prover Manual
Copyright© 2014 Eagle Research Corporation®
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Test Volume
This selection screen can be disabled by Field Manager™. If it does not appear on the Transfer
Prover display skip ahead to the next selection screen description. If this value is skipped, the
default value specified in Field Manager™ is used as the test volume.
This value defines how much air will flow though the master meter for each proof cycle. Since this is
a volume based criteria, the time for different flow rates can vary dramatically. For instance, a test
using a 3MR master meter at a flow rate 300 CFH will take 10 times as long as the same test at a
flow rate of 3000 CFH. With the gate box this difference is negligible. However, when using the
push button option, the user may want to select flow rates that make the test last at least 45
seconds in order to minimize the user input error.
After choosing the desired value, press to go to the next selection screen.
Active Screen
At this point in the process, the Transfer Prover has been configured for a particular test, the desired
flow rate has been specified, and leak testing has been performed. The screen below is referred to
as the Active Screen.
The first line is a header that specifies the master meter type. The second line is the flow rate as
calculated by the master meter. This value updates in real time as the hand valve on the blower
hose is adjusted. The third line is differential pressure. This value is in inches of water and refers to
the differential pressure between the inlet of the master meter and the inlet of the meter under test.
A negative value is a good indication something is not setup correctly or the proof is not properly
configured. This item can be disabled in Field Manager™ in the event pressure compensation is not
needed.
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The fourth line alternates between the field meter temperature (FMT) and the master meter
temperature (MMT). The FMT is determined by the external temperature probe connected to the
Transfer Prover. The MMT signal is fed into the Transfer Prover through a temperature probe inside
the master meter. This pair of values can be disabled in Field Manager™. In order to get the best
results from the Transfer Prover, the temperatures should be stable. They will most likely not be
equal, but should be settled before performing a test. For instance if a meter had gas flowing though
it at 60 F, and then a blower begins pulling 75 F air though it, the temperature of the field meter will
increase from 60 F to 75 F at a rate proportional to the flow rate.
When the flow rate, differential pressure, and flow temperatures are satisfactory, press to go
to the next menu.
Countdown Screen
The countdown screen keeps the user informed of the progress of a proof as it happens. The Cnts
Left parameter shows the user how many counts remain to be received from the meter under test.
This value varies depending on the Test Volume selected during the configuration process. The
countdown is uniform, and therefore can be used to estimate the time remaining for a given proof.
The DP, MMT, and FMT update periodically. This feature provides the user with a way to monitor the
progress of the test and gage the stability of the flow parameters during the calculation phase of the
proof.
Results Screen
The results screen show the percent error, percent accuracy, and/or percent proof. The type of error
is configurable in Field Manager™. This screen can display all three, any two, or just one error.
The Accept/Reject flag is used to expedite reporting in Field Manager™. Every proof is stored in the
RTU history regardless of the Accept/Reject selection. When the history from the Transfer Prover is
loaded into Field Manager™, this flag is used to determine the default proofs selected for reporting.
XARTU/TP™ Transfer Prover Manual
Copyright© 2014 Eagle Research Corporation®
Page | 17
Press to reject the history value. Press to accept the value.
After leaving the results screen, the menu returns to the active screen. From here the user can
adjust the flow rate and start another proof. The configuration parameters remain the same.
Self Test
Master Meter
Each Eagle Research® Transfer Prover can be configured to support multiple master meters. This
selection screen is used to specify which master meter is connected to the Transfer Prover for the
current proof. Choose the appropriate option, and then press to go to the next selection
screen.
If the Transfer Prover is only configured for one master meter, this screen will appear for a brief
period and then automatically advance to the next screen.
XARTU/TP
This screen will only appear briefly. It gives the user a simple way to view the Transfer Prover
firmware version. This screen automatically advances to the next screen.
Adjust Flow to 1000 CFH
XARTU/TP™ Transfer Prover Manual
Copyright© 2014 Eagle Research Corporation®
Page | 18
TRANSFER PROVING
Larry K. Wunderlich
Centerpoint Energy Entex
4220 Laura Koppe, Houston, Texas 77016
INTRODUCTION
Transfer proving was initially developed to provide an
easier and more accurate field meter proving method.
Because of the capacity capabilities of transfer provers
(2000 CFH to 80,000 CFH) transfer provers are utilized
in meter shops where bell prover capacity is limited and
allow for shop testing of the larger capacity meters.
All transfer provers are available to the gas industry
compute the following formulae:
Master Meter Volume
Equation 1 - % Uncorrected Proof = —————————— X 100
Field Meter Volume
ATM Press-Master Press Drop
Equation 2 - % Pressure Correction = —————————— X 100
TRANSFER TESTING SYSTEM
In the typical transfer testing system, air or gas passes
through the meter under test (field meter) and then
through the “Master” meter. The vacuum method of
testing is basic to all commercially available provers.
Atmospheric air is drawn through the field meter and
prover by the blower system. Temperature and pressure
differences are measured to enable correction of the data
to a common base of comparison. The rotary meter
transfer proving system is not affected by specific gravity
or relative humidity of the flowing gas since under normal
conditions no condensation or change of moisture
contact would occur as the gas passes from the field
meter to the master meter. It is a volumetric test in which
the test time is not a critical variable. Automatic operation
minimizes chances for human error, and built-in selfcheck features assure reliable system performance. The
ROOTS Model 5 Transfer Prover System is typical of the
commercially available units and will be utilized in this
discussion. Other units may differ slightly in shape, size,
or performance, but the base operating principles are
the same.
The prover System consists of one or more rotary positive
displacement master meter(s) mounted on a wheeled
cart. The master meter is calibrated over a flow range of
100 to 10,000 CFH for a 10M master meter of 35 to 2,000
CFH for a 2M master meter. This range covers the testing
of larger diaphragm meters as well as most rotary meters.
Blowers mounted downstream of the meters are used
when air is the testing medium. On air tests, the blowers
discharge to atmosphere through a muffler or silencer
which minimizes noise when testing in public areas or in
shops where noise could be objectionable.
Comprehensive tests have demonstrated compliance
with OSHA regulations concerning acceptable noise
levels. The connection from the field meter to the prover
is made with a 25˚ length of flexible hose equipped with
quick disconnect fittings. In addition, a cable is required
for temperature, pressure, and pulser connections on a
field meter.
ATM Press - Field Press Drop
Field Meter Temp ‘R
Equation 3 - % Temperature Correction = —————————1 X 100
Master Meter Temp ‘R
% Uncorr % Press % Temp
Proof X Corr + 100 X Corr + 100
Equation 4 - % Corr Proof = ———————————————
10,000
Testing can be done automatically or manually. When
testing automatically, the index or instrument is removed
from the field meter and a pulser unit installed to count
the output shaft revolutions. When testing a meter whose
index cannot be removed, a retroreflective scanner may
be utilized or a remote start-stop switch in lieu of the
pulser.
The standard transfer prover operates on a 115 VAC
±10%, 47-60 Hz. Power consumption with blowers on
high is approximately 1000 watts, but satisfactory
operation can be obtained in the voltage range of 95 to
130 VAC. Special provers have been designed for
operation on 230 VAC.
The proving system has been designed for operation by
one man with a minimum of effort. At Centerpoint Energy
Entex a van is used for transporting the Model 5 prover.
The accuracy and repeatability of the transfer prover
system is related to the permanent accuracy
characteristic of the rotary positive displacement master
meter. For convenience, a direct readout of the proof of
the field master is provided by using a simple but effective
method of obtaining a master meter curve of 100%
accuracy over the full working range.
The master meter incorporates a pulse unit for generating
contact closures representing the flow units from the
master meter. Provisions have been made in the
computer software to add/subtract in extra counts
required to produce a 100% accuracy curve for the
master meter.
2003 PROCEEDINGS
PAGE 135
AMERICAN SCHOOL OF GAS MEASUREMENT TECHNOLOGY
The actual preset correction necessary to linearize each
specific master meter curve is determined from a factory
calibration with a bell or piston prover. A chart is provided
with each prover, showing the calibration curve.
OPERATION
The Model 5 Proving System consists of the master
meter(s), blowers, controller, and laptop computer.
Operation of the Model 5 Transfer Proving System can
be broken down into five sections:
1.
2.
3.
4.
5.
Powering up of the system.
Making field meter connections.
Purging the meter and leak testing.
Selecting and starting the test(s).
Running the test and saving the results.
4. If the field meter pulser is being used rather then the
manual start/stop button, install the field meter pulser
on the instrument drive platen of the field meter.
Ensure that the instrument drive properly engages
the pulser and that the pulser shaft is centered over
the meter drive shaft. The pulser drive coupling may
require adjustment to engage the meter drive shaft.
Plug the cable into the field junction box.
5. If the manual start/stop button is to be used, plug
it’s cable into the field junction box instead of the
pulser.
6. Connect one end of the 25 foot prover hose to the
outlet of the field meter.
PURGING AND LEAK TESTING
Reasonability tests are run on the signal inputs to the
controller to determine that the transducers are properly
connected prior to starting a test run and that
measurements taken during a test run are within
reasonable limits.
The Model 5 Transfer Prover can be set-up to require
purging of the field meter or not require purging for shop
use. You can also require or not require a leak test. If a
purge is required the blowers will not start for testing
until the operator does a purge of the field meter.
POWERING UP THE SYSTEM
1. Connect one end of the 25 foot prover hose to the
camlock on the Model 5 silencer. The other end
should be hooked to the field meter.
This step should be performed first as it allows time for
the controller to warm-up and stabilize prior to running
a test.
1. Plug the line card from an AC power source into the
controller.
2. From the laptop software menu, select the purge
option and run the blowers to purge the field meter.
2. Connect the laptop computer AC cord to the laptop
receptacle on the controller.
3. Seal the inlet to the field meter, move hose from
silencer to the inlet of the Master Meter and run leak
test. This takes approximately 30 seconds and a
pass or fail message will be isplayed.
3. Connect the RS232 cable between the laptop
computer and controller.
4. Identify and eliminate any leaks as they will affect
the accuracy of the tests.
4. Turn on the controller power switch and then the
laptop computer.
SELECT AND START TEST
5. Go into the Model 5 laptop computer software and
verify master meter serial numbers. This ensures
proper presets are loaded.
FIELD METER CONNECTION
Connections of the field meter sensors and pulser (if
used) should be done next.
1. Connect the field junction box cable to the controller.
2. Install the field meter temperature sensor in, or near,
the inlet port for rotary meters and at the outlet port
for turbine and diaphragm meters. The tip of the
sensor should be in the center of the flowing air
stream. Plug the cable into the field junction box.
3. Connect the pressure lines from the field junction
box to the inlet of the field meter (and outlet if rotary
meter differential is to be read during testing).
PAGE 136
2003 PROCEEDINGS
AMERICAN SCHOOL OF GAS MEASUREMENT TECHNOLOGY
Forty preconfigured tests can be run by simply selecting
the desired tests for a particular meter. Each test can be
run at three different flows and each flow can be run
twice. The tests can be cascaded for more flow rates if
desired. Flows are set and controlled by varying blower
motor speed which reduces noise. The following items
must be selected to configure for a manual test:
1.
2.
3.
4.
5.
6.
7.
8.
Prover Capacity (2M, 10M, 80M)
Test Control Mode (ID, OPTO, Manual)
Meter Output (UC, TC, PC, TCPC)
Drive Rate (What each pulse represents.)
Test Volume (Even multiple of drive rate.)
Flow Rate (Up to three flows.)
Base Temperature Correction (If Required.)
Base Pressure Correction (If required.)
RUN TEST AND SAVE RESULTS
TEST SET-UP MODIFICATIONS
When the operator starts the test, the computer, via the
controller, will start the blowers, stabilize flow as highest
rate selected and begin test. At the end of the first run,
results will be displayed and the blowers will stabilize
for the next run. At the completion of the tests, the
operator can view any particular run. The results can be
saved and/or printed. The operator will be prompted to
fill in some information for the report. The layout
appearance of the reports are customer configurable.
The transfer prover is an extremely versatile and flexible
test device and has been used to test meters with 1,000
cubic foot drive rates, temperature compensated
outputs, pressure compensated outputs, and intermittent
outputs. Information concerning special test techniques
or particular test problems can be obtained from the
prover manufacturer.
TESTING RESULTS
The feasibility of using a rotary positive displacement
meter transfer testing system has been clearly
established. Tests have confirmed the accurate
performance of the equipment. The increase in
productivity, the speed of testing, the avoidance of test
errors, and the savings in shop test facilities make
transfer provers an attractive and economical addition
to the array of meter test equipment.
What is the accuracy of this testing device? Results from
extensive series of tests show that the ROOTS Transfer
Prover duplicated a bell prover within ±0.1% on overall
average results and had a standard deviation of the less
than 0.5%. The test included a large number of different
types and sizes of diaphragm meters. The bell prover
was in a temperature controlled environment, but the
transfer prover operated in a room without temperature
control. Repeatability has been found to be ±0.1%.
A warm-up period has been found to be desirable in
testing diaphragm meters which have been inactive.
Such meters are occasionally encountered in the meter
shop testing, and a running period of a few minutes will
allow enough exercise of the moving parts to restore
normal meter friction and assure representative test
results.
CONCLUSION
The development of the portable transfer proving system
with computer enhancements gives measurement
personnel another useful and reliable tool for testing gas
meters. The ability to test meters in the field and spot
inaccurate meters and adjust them without removing the
meter saves not only time but money. Although the
primary usage of transfer proving has been for field
testing, increasing numbers are being utilized in meter
shops and provide a valuable supplement to existing test
facilities.
Minor variations in blower operation due to supply
voltage fluctuations may occur but will vary the actual
flow rate only slightly. Tests have shown that fluctuations
which might have invalidated the test run by other test
methods did not influence the transfer prover test results.
Larry K. Wunderlich
2003 PROCEEDINGS
PAGE 137
AMERICAN SCHOOL OF GAS MEASUREMENT TECHNOLOGY
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