TCS 682 SERIES Installation and operation manual

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© Total Control Systems 2010
Fort Wayne, Indiana U. S. A.
ENGINEERING MANUAL
682 SERIES PISTON FLOW METER

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TABLE OF CONTENTS
Page No.
Table of Contents
1
Quote and Purchase Specifications
2
Meter Design
3
Meter Type Classifications
4
Meter Operating Specifications
5
Meter Selection Factors
Weights & Measures
5
Accuracy
5
Product Characteristics
5
Material Compatibility
6
Flow Rate
6
Pressure
6
Temperature
6
Lubricity
6
Suspension and Suspended Solids
7
Foreign Materials
7
pH
7
Viscosity
7
Pressure Loss
8
Operating Limits
9
System Design
Meter Selection
10
Air Elimination
10
Control Valve
10
Best Plumbing Configuration
10
Protection From Debris
11
Thermal Expansion
11
Hydraulic Shock (Water Hammer)
11
Products that Dry/Congeal/Crystallize
12
Calibration
12
Typical System Installation
12 –14
Meter Calibration
15 –18
Product Depletion (Split Compartment)
18 –19
Calibration Procedure
20
682 Series Materials of Construction
21
Chemical Compatibility
21 –33
Approximate Weights
33
Metric Conversion Guide
34
Strainer Screen Size
34
Registration Specifications
Gear Plate Information
35
Pulse Output
35
Glossary
36 –38
Material Safety Data Sheet (MSDS) for Calibration Fluid
39 –42

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QUOTE & PURCHASE SPECIFICATIONS
There are many advantages available only to Total Control Systems meters, such as performance,
installation, operating, and maintenance. In order to assure you of receiving a Total Control
Systems meter, we suggest that the following statements, along with a TCS model number and
description be included when issuing quote and purchase specifications.
“Flow Meter shall be of positive displacement design having reciprocating piston motion, with
in-line flange connections.”
NOTICE
Total Control Systems (TCS) shall not be liable for technical or editorial errors in this manual or
omissions from this manual. TCS makes no warranties, express or implied, including the
implied warranties of merchantability and fitness for a particular purpose with respect to this
manual and, in no event, shall TCS be liable for special or consequential damages including, but
not limited to, loss of production, loss of profits, etc.
The contents of this publication are presented for informational purposes only, and while every
effort has been made to ensure their accuracy, they are not to be construed as warranties or
guarantees, expressed or implied, regarding the products or services described herein or their use
or applicability. We reserve the right to modify or improve the designs or specifications of such
products at any time.
TCS does not assume responsibility for the selection, use or maintenance of any product.
Responsibility for proper selection, use and maintenance of any TCS product remains solely with
the purchaser and end-user.
All rights reserved. No part of this work may be reproduced or copied in any form or by any
means –graphic, electronic or mechanical –without first receiving the written permission of
Total Control Systems, Fort Wayne, Indiana USA.

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METER DESIGN
The 682 meter is a true Positive Displacement Meter, with the inlet and outlet on the same
horizontal plain (straight in - straight out). Within the meter, three plungers are fitted within
their respective cylindrical measuring chambers. The plungers are joined to a wobble plate,
which has a shaft extending from its upper surface. The wobble plate features a valve pivot on
the underside of the plate. The valve pivot drives a sliding valve from cylinder operning to
cylinder opening as product flows, controlling the sequence of events.
The wobble plate shaft is always held at an inclined position by the center gear post. This allows
the plate to tilt from side to side but it is prevented from rotating by four guide pins on the pivot
bracket assembly.
As product enters the meter, it initially flows into the meter chamber located in the upper meter
housing. As the sliding valve travels around the meter chamber, it alternately opens and closes
the imlet and outlet of each measuring cuylinder in turn. The sliding valve starts in position with
one measuring cylinder open to the downstream flow. The plunger for the corresponding
cylinder is in the upper position with the cylinder below open to the outlet. With the upper
housing full of product at line pressure, the differential pressure between the inlet and outlet will
force the plunger to the bottom of the cylinder, expelling the product in the measuring cylinder to
the meter outlet. As this occurs, another plunger is forced from the down position to the upper
position. As this happens, the sliding valve moves to open the inlet of this cylinder. As the
plunger moves upward, it draws product into the bottom of the measuring cylinder through the
open port in the meter chamber. Once this plunger reaches the upper position, the cycle will
repeat, so long as product continues to enter the meter. If product flow stops, pressure in the
meter equalizes and motion stops. Thus the meter only operates when product is flowing.

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METER TYPE CLASSIFICATION
SP STANDARD PETROLEUM
For metering refined petroleum products such as Gasoline, Fuel Oils, Diesel, Bio-Diesel,
Kerosene, Motor Oils, etc.
SPA STANDARD PETROLEUM (AVIATION)
For metering refined petroleum products such as Aviation Gasoline, Jet Fuels, Gasoline, Fuel
Oils, Diesel, Bio-Diesel, Kerosene, Motor Oils, etc.
SPD STANDARD PETROLEUM (DUCTILE IRON)
For metering alternative fuels such as Natural Gasoline, Ethanol, Methanol, Bio-Diesel, Aviation
Gasoline, Fuel Oils, Diesel, Motor Oils, etc.
AF ALL FERROUS
For metering Pesticides, Nitrogen Solutions, Fertilizer, Chlorinated Solvents, Paints, Inks,
Alcohols, Adhesives, Motor Oils, Molasses, Corn Syrup, Liquid Sugars, etc.
SS STAINLESS STEEL
For metering the same liquids as the SP, SPA, SPD, IP, IC and AF flow meters, but includes
food processing and special handling fluids such as Nitric, Phosphorus and Glacial Acetic Acids,
Anti-Icing Fluids, Vinegar, Fruit Juices, etc.

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METER OPERATING SPECIFICATIONS
Type
Reciprocating 3 Piston Positive Displacement
Connections
1-1/2” NPT Flange Connection Standard
1” and 2” NPT, BSP, Slip Weld or ANSI Flange Connections Optional
Flow Rate
Minimum: 0.2 GPM (0.76 LPM)
Maximum: 50 GPM (189 LPM)
Working Pressure
150 PSI maximum (10.5 Bar)
Working
Temperature
-20°F to 160°F (-28.9°C to 71°C)
Units of Measure
1/10th U.S. Gallons Standard
Litres, Pounds, Quarts, Imperial Gallons Optional
Others available upon request.
METER SELECTION FACTORS
WEIGHTS & MEASURES
Before any meter can be specified, knowledge of each application is required. If the liquid is to
be sold through a metered delivery, domestic or international certification from a governing body
may be required. Total Control Systems strictly adheres to all domestic and international
metrology conformance regulations for the custody transfer of fluids. For questions regarding
weights and measures approvals or other issues, please consult factory.
ACCURACY
The 682 meter’s accuracy (percent of error over or under the zero – error level) remains within
design parameters (+/- 0.1%) over its minimum rated flow range to its maximum rated flow
range for custody transfer meter requirements. This percentage meets or exceeds the Wholesale
and Vehicle accuracy requirements for accurate custody transfer of product, as specified in the
National Institute of Standards and Technology (NIST) Handbook 44.

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PRODUCT CHARACTERISTICS
A) Material Compatibility
Consult the Total Control Systems CHEMICAL COMPATIBILITY charts on pages 21 to 33
of this manual to find the suitable materials and meter type for the product to be measured.
Products incompatible with meter materials will potentially pose harm to personnel, reduce
the accuracy and operational life of the meter and contaminate the liquid andcould
B). Flow Rate
The minimum and maximum system rate of flow must be determined for the selection of
flow meter. The flow rate of the system is dependent upon the product viscosity; the desired
meter configuration, the pump capabilities of the system and the plumbing configuration.
C) Pressure
Consult the specified maximum working pressure of the meter under flow meter type and
pressure rating. All meters meet the European Pressure Equipment Directive (PED) No.
97/23/EC. Failure to adhere to the maximum allowable pressure may potentially cause a seal
leak or casting rupture.
D) Temperature
The operating temperature has a great effect on the meter seals. Temperature also has a
relationship to the operating pressure as it relates to the flow meter castings. It will be
necessary to reduce the maximum rated working pressure as the operating temperature
increases. Any metering system operating over 180F (82 C) will require at least a one (1)
foot registration extension to protect the registration devices. Increase in temperature may
increase the corrosion rate of some products.
1) Seal Temperature Rating
Viton -31F to 400F -35C to 204C
Simriz -40F to 450F -10C to 230C
Teflon -20F to 500F -30C to 260C
2) Pressure rating at elevated temperatures.
Temperature
Reduced Maximum Operating Pressure
150 F
150 PSI
200 F
100 PSI
250 F
75 PSI
300 F
50 PSI
E) Lubricity
The lubricity or non-lubricity of the product will be a major factor in determining the
operational life of the meter. Products with lubrication will reduce friction between two
metal surfaces and help dissipate heat. Products with no lubrication may potentially redice
the life of seals and bearings.

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F) Suspensions & Suspended Solids
Products with high percentages (5%) of suspensions or suspended solids, or any hard solids,
such as sand, are not recommended for the 682 series meter. Products with a low percentage
of soft suspensions or suspended solids (<5%) may be metered at a reduced flow rate. It is
recommended that the flow be reduced by 20% from the flow rate for a similar product
without suspensions or suspended solids.
G) Foreign Materials
Products that are to be measured may have foreign materials present. The inlet side of any
positive displacement meter should be equipped with a strainer to protect the meter and
accessories from damage in the system. The strainer should be suitable for 1-1/2” or 2”
piping with an appropriate screen mesh size. A minimum of 40-mesh screen is
recommended for petroleum service.
H) pH
The resistance of any metal to the effects of high or low
PH is difficult to calculate because of the varying
concentrations and corrosiveness of fluids, particularly
blended products. At right is a generalized
recommendation for pH resistance for metals used in
the Series 682 meter. For specific application, consult
the factory.
pH SCALE
NEUTRAL
0
1
2
3
4
5
6
8
9
10
11
12
13
14
◄——— ACID REACTION ———
——— ALKALINE REACTION ——►
7
I) Viscosity
Viscosity is the property of a fluid that is a measure of its resistance to flow. Among the
earliest to express this quantitatively was Sir Isaac Newton. He reasoned that the viscosity of
a liquid was proportional to its shear stress (or resistance to shear). In other terms, viscosity
is basically constant with shear and flow rate. Liquids that behave in this manner are referred
to as “Newtonian” liquids. Petroleum fluids, water and similar chemicals are categorized as
Newtonian liquids.
Other types of fluids are grouped into a general category called “Non-Newtonian”. Among
the fluid types that are categorized as non-Newtonian are dilatants, plastic, pseudoplastic and
thixotropic liquids. Non-Newtonian liquids are characterized by viscosity that changes with
the rate of shear as compared to the Newtonian fluids where viscosity is essentially a
constant. As a consequence, the performance of a fluid through a flow meter is much more
predictable for Newtonian fluids than for Non-Newtonian liquids.
Many of the more viscous liquids pumped through the 682 series rotary flow meter are
plastic and pseudoplastic and as such are reduced in effective viscosity after being pre-
sheared by the pump.
Recommended
Material pH Range
Aluminum 5 –8
Ductile Iron 5.5 –11
Ni-Resist 5.5 –14
Stainless Steel 0 –14

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The diagram below shows how viscosity varies as a function of shear rate on various types of
liquids. As noted, some fluids may not be suitable for metering with the 682 Series flow
meter. See Section K Operating Limits for additional considerations concerning viscosity.
J) Pressure Loss
Pressure drop across a flow meter is the difference between of the inlet and outlet pressure of
the flow meter while it is operating. As flow rate increases through the meter, the pressure
drop will increase as shown in the chart below. When the metering system includes any
accessories such as an air eliminator or a valve, each of these devices will add approximately
5 PSI to the overall pressure drop for the meter system.
1) Thixotropic Liquids (Plastic and Peudoplastic):
Viscosity decreases as shear rate increases. Typical
liquids include gels, Latex paints, lotions,
shortening, mayonnaise, printers ink, hand cleaner
and yeast.
2) Newtonian Liquids:
Viscosity remains unchanged with shear.
3) Dilatants Liquids:
Viscosity increases as shear rate increases. Most
liquids in this category are unsuitable with PD flow
meters. Examples include clay, slurries and some
confectionary bases.

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K) Operating Limits
The viscosity of the product to be metered will have a direct impact on the flow rate at which
the metering system can effectively operate. The following chart is a flow meter selection
guide indicating the relationship between viscosity and flow rate. If the desired system flow
rate and fluid viscosity fall outside the recommended operating limits, the flow rate must be
reduced.
VISCOSITY CONVERSION
(Specific Gravity = 1)
SSU
SSU
SSU
SSU
CPS
Saybolt
CPS
Saybolt
CPS
Saybolt
CPS
Saybolt
Centipoise
Universal
Centipoise
Universal
Centipoise
Universal
Centipoise
Universal
1
31
200
1,000
900
4,300
7,000
32,500
2
34
220
1,100
1,000
4,600
8,000
37,000
4
38
240
1,200
1,200
5,620
8,500
39,500
7
47
260
1,280
1,300
6,100
9,000
41,080
10
60
280
1,380
1,400
6,480
9,500
43,000
15
80
300
1,475
1,500
7,000
10,000
46,500
20
100
320
1,530
1,700
8,000
15,000
69,400
25
130
340
1,630
1,800
8,500
20,000
92,500
30
160
360
1,730
1,900
9,000
30,000
138,500
40
210
380
1,850
2,000
9,400
40,000
185,000
50
260
400
1,950
2,200
10,300
50,000
231,000
60
320
420
2,050
2,400
11,200
60,000
277,500
70
370
440
2,160
2,500
11,600
70,000
323,500
80
430
460
2,270
3,000
14,500
80,000
370,000
90
480
480
2,380
3,500
16,500
90,000
415,500
100
530
500
2,480
4,000
18,500
100,000
462,000
120
580
550
2,660
5,000
23,500
125,000
578,000
140
690
600
2,900
5,500
26,000
150,000
694,000
160
790
700
3,380
6,000
28,000
175,000
810,000
180
900
800
3,880
6,500
30,000
200,000
925,000
Centistokes
=
Centipoise
Centipoise
=
Centistokes x Specific Gravity
Specific Gravity

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SYSTEM DESIGN
Meter Selection
The flow meter must be carefully chosen using the information in the Meter Selection Factors
section above. The meter must be selected based on the operating system and product
characteristics. System variables include flow rate, temperature and pressure. The product
characteristics include the material compatibility, lubricity, viscosity, suspensions, pH, and other
factors. Failure to select the correct flow meter may result in serious injury, system failure or
reduced system performance.
Air Elimination
In any system I which the supply tank may be completely drained or where multiple products
manifold into one metering system, there is a risk of air being present in the fluid stream. The
solution is an air or vapor eliminator located before the flow meter to vent the air or vapor from
the system before it can be measured. Air or vapor elimination is required for all weights and
measures regulatory approvals in custody transfer applications.
Control Valves
Safety and isolation valves should be used throughout the metering system. In any pumping
system where there is one pump and multiple flow meters, a digital or hydro-mechanical Rate-
of-Flow control valve must be used at each flow meter to prevent the meter from operating above
its maximum flow rating.
Best Plumbing Configuration
1) Flow meter must have secure mounting to a riser stand or the foundation.
2) The inlet and outlet piping must be securely supported, in a manner that does not allow pipe
stress on the flow meter. The meter must also be supported and must not hang from the pipe
fittings.
3) System must be designed to keep the flow meter full of liquid at all times. Meter inlet and
outlet should be lower than the associated system plumbing (in the SUMP POSITION).
4) System piping must be of at least 1-1/2” or larger thoughout the entire metering system. This
will allow for minimal pressure loss.
5) The pipe should be laid out as straight as possible to reduce pressure loss from flow
restrictions.
6) It is not necessary for the air eliminator to be installed directly to the meter. It may be
installed upstream from the meter. For effective operation of the air eliminator, it should be
mounted between the meter and any valves, pipe tees or any other potential places where air
may enter the system.
7) The metering system must include a means for calibration.

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Protection From Debris
On new installations, care must be taken to protect the meter from damage during start-up. It is
recommended that a strainer be installed upstream of the meter. Damage may result from the
passage through the meter of dirt, sand, welding slag or spatter, thread cuttings, rust, etc.
It is recommended that a spool be constructed to be installed in place of the meter until the
system is flushed. The spool is a flanged length of pipe equal in length to the meter and its
attached accessories. The meter may be left in place if the plumbing can be temporarily
bypassed around the meter to protect the meter from debris. Once the system has run “clean” for
a period of time the meter may be reinstalled or temporary protective devices removed.
Thermal Expansion
Most liquids will expand and contract with temperature. In any system where there is a chance
for liquid to be captured between closed valves without relief, there is a risk of thermal
expansion. This condition can create dangerously high pressures within the system. For every
one degree of temperature increase, there is a corresponding pressure increase of 126 PSI (8.69
BAR).
Care must be taken in designing the system where thermal shock may occur by implementing
Pressure Relief Valves or Thermal Expansion Joints in the system design.
Hydraulic Shock (Water Hammer)
Hydraulic shock is a rise in pressure that occurs when an operating system has immediate change
in direction of flow. This can be due to a sudden valve closure while the system is operating at a
at a high flow rate. Hydraulic shock can damage any item in the way of the product flow such as
the internal parts of the meter, valves, and pump. System design and improper operating
procedures will increase the risk of this problem. The use of 2-stage preset control valves or
surge suppressing bladders or risers will help reduce or eliminate this problem.
The shock pressure when a valve is closed quickly is computed as follows. The maximum
recommended shock pressure is 6 PSI.
Shock Pressure (PSI) = 63 x Velocity (FPS)
In order to eliminate hydraulic shock from sudden valve closure, the valve closure rate must be
reduced. The time required to close the valve so that the line pressure will not exceed the normal
pressure at zero flow is calculated as follows.
Time (seconds) = 0.027 x L x V
N –F
V = Velocity in Feet/Seconds
L = Length of pipe before the valve in feet
N = Line pressure at no flow
F = Line pressure at full flow

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Products that Dry/Congeal/Crystallize
There are many liquids that crystallize, harden and/or solidify on contact with air or with an
increase in temperature. A proper system design and a good understanding of the product being
measured will help to avoid the possibility of air entering into the system and the product being
affected.
Calibration
The meter shall be tested and calibrated with the product it is intended to measure when installed.
Total Control Systems shall not be responsible for loss of product or any damages resulting from
the end user’s failure to test the meter to insure proper calibration. Every 682 Series meter is
tested and calibrated at the factory to ensure that it may be calibrated in your system.
See pages 15 –20 for instructions on how to calibrate the 682 Series meter.
It is the end user’s responsibility to report this device to the local Weights and Measures officials
for inspection prior to the the meter being put to use.
Refer to the Material Safety Data Sheet on pages 39 –42 for informaiton on the calibration fluid
used in factory testing.
Typical System Installations
See pages 13 and 14 for diagrams of typical metering system designs. These diagrams are not
definitive. Actual system requirements vary greatly from installation to installation. System
design is the reponsibility of the end user.

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- 14 -

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METER CALIBRATION
The method of proving should be selected, and necessary provisions made, during the design
stage of the installation. Of the most commonly used systems, portable provers have the
advantage of more closely reproducing the condition under which the product is normally
delivered.
Use Accurate Prover
A volumetric testing prover is a scientifically designed test measure, having proper drainage
means built in, a calibration gauge glass neck, and protection against deformation (which causes
volume changes). Scientifically designed provers are commercially available
No other sort of home-made or non-scientific prover such as a truck compartment, tank or drum
should be used. A homemade prover will most likely prove to be unsatisfactory. The use of
such a prover may cause expensive errors due to inaccurate meter calibration.
Even scientifically designed provers should be checked periodically for accuracy and care must
be taken to ensure these provers are not damaged during use, transportation or storage. A dent in
a prover will affect its measurement accuracy. Weights and Measures officials have been very
cooperative in giving assistance to checking privately owned volumetric provers.
Recommended size of test measure:
The prover capacity should be equal to at least one minute’s flow through the meter at its
maximum rate.
A 50 Gallon prover would be required for a 682 Series meter operating at full flow rate.
Setting a Prover
The prover must be set level, using the levels provided on the prover, or using separate leveling
means. This insures consistent results from test to test and when moving the prover from meter
to meter.
Where to Test a Meter
The best place to test is in its normal operating position, as opposed to a separate test stand. In
this way, the correctness of the installation and of the operational conditions will be verified by
the test. Always test a meter with the same liquid it is to measure, because a difference in
viscosity, temperature and system plumbing can have an affect on meter accuracy.
Discharge Line from Meter
Where a portable prover is used, the liquid should be discharged into the prover in the same
manner as a normal delivery would be made. In cases where a special test connection must be
used, the discharge line must be arranged to drain to the same point on each test to ensure
repeatable test conditions. Any valves used to control the meter flow rate and the start and stop
of the fluid flow must be located on the discharge side of the mter.

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Wetting the Prover
The calibrated accuracy of a prover is determined on its wet measure capacity by its
manufacturer, so the prover must be wetted prior to actual testing.
To wet the prover, follow this procedure. Reset the meter register to zero, and fill the prover to
the zero or 100% marking of the scale. Disregard the meter reading. Drain the prover, and reset
the register. The first meter reading is disregarded as there will be a slight difference between a
wet and a dry prover fill.
After the prover has drained, allow the tank to drain for a set time. Thirty seconds is a typical
drain time, with the count beginning as soon as the fluid empties or is dumped from the prover.
It is important that whatever amount of time is selected, that this same interval be used for all
tests to ensure repeatable test conditions. If a considerable period of time is to elapse between
tests and the prover is emptied, then the prover must be re-wetted prior to subsequent testing.
The re-wetting operation can be eliminated by allowing the prover to remain full until the next
test is to be run.
Making the Tests
Once the prover is wetted, the accuracy tests can begin according to this procedure. Reset the
register to zero, and run the required tests through the meter. Typically, a flow meter will be run
at several flow rates. Do not exceed the maximum recommended rate of flow for the meter. The
difference between the fluid volume as measured in the prover is compared to the reading of the
register on the meter. An error caculation is made, expressed as a per cent. The per cent errors
at each flow rate are compared to arrive at an overall error percentage. The overall error must
fall within certain parameters. In addition, multiple tests at any given flow rate must be
repeatable within a certain percentage.
Accuracy test and repeatability requirements vary from jurisdiction to jurisdiction. Constult your
local weights and measures officials for guidance on the specific requirements for the area in
which the installation is located.
Determining Test Results
Run the meter to deliver a volume of product that corresponds to the prover capacity. Read the
volume of product on the calibrated plate on the neck of the prover. This reading will typically
be in cubic inches. If so, the percentage error can be readily computed with the following
information:
(a) One gallon equals 231cu.in.
(b) A 100-gallon prover holds 23,100cu.in. Thus, 23.1cu.in. represents 0.1%
error.

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The National Institute of Standards and Technology, in its NIST Handbook 44 specifies a
tolerance of plus or minus the following:
METER TOLERANCE
Acceptance tolerances apply to new meters and repaired meters after reconditioning.
Maintenance tolerances apply to meters retested after being in service. Special tolerances are
applied at low flow rates and also for tests of the system air eliminator (See Product Depletion
Test below).
Some US and most international jurisdictions have their own test requirements and tolerances. It
is the responsibility of the end user to contact the proper local authorities and to ensure that the
correct test requirements are applied.
Repeatability
NIST Handbook 44 requires that multiple tests conducted at approximately the same flow rate
and draft size shall have test results that do not exceed 40% of the absolute value of the
maintenance tolerance. Also, the results of each test must be within the applicable tolerance. So
for a hehicle meter with a maintenance tolerance of 0.30%, all readings at one flow rate must be
within 0.12% (40% of 0.30). All readings at this flow rate must also be within the + or –0.30%.
Changing Meter Calibration
Refer to page 20 for the procedure to change meter calibration. Any change in the meter
calibration adjustment will change the delivery in the same amount for all rates of flow. That is,
the calibration curve retains its shape, but is shifted up or down on the y-axis of the graph.
If a meter test indicates satisfactory performance at one flow rate, but is shown to be
unsatisfactory at a different flow rate and the overall accuracy is less than twice the required
tolerance (2 times +/-0.30% for example), the meter can be adjusted to shift the curve up or
down so that the entire error curve fits within the required limits. Small adjustments should be
made so as to avoid overshifting the curve so the meter falls out of accuracy in the other
direction.
If a meter test indicates satisfactory performance at one flow rate, but is shown to be
unsatisfactory at a different flow rate and the overall accuracy is more than twice the required
tolerance, changing the calibration will not remedy this condition. Shifting the curve will simply
indicate an out of teolerance condition at a different flow rate. In this case, check the minimum
flow rate and ensure that the testing is at or above the minimum recommended rate of flow for
the meter. If the meter flow rate is within recommended limits, the meter likely requires
cleaning or repairs.
Tolerance
Indication of Device
Acceptance Test
Maintenance Test
Special Test
Wholesale
0.20%
0.30%
0.50%
Vehicle
0.15%
0.30%
0.45%

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Temperature Correction
If the conditions of testing are such that there will be a change of more than a few degrees in the
temperature of the liquid between when it passes through the meter and when the prover is read,
it will be advisable to make a temperature correction to the prover readings. To do this, it is
necessary to install thermowells; to take readings of the temperature of the liquids in the meter
and in the prover. Corrections to the indicated volume of both the prover and register readings
can be made with National Standard API Tables.
Product Depletion (Split Compartment) Test
The purpose of a product depletion test is to verifiy the proper operation of air elimination in the
event that the metered product storage tank is pumped dry. This test is necessary for meters that
may drain a tank completely, such as a vehicle tank meter. Due to the nature of the testing which
introdces air into the system, appropriate attire and protection is required. Testing should be
conducted with caution.
Multiple-Compartment Test Procedure:
1) Begin the test from a compartment (ideally the largest compartment) containing an amount of
fluid equal to or less than one-half the nominal capacity of the prover being used. Operate the
meter at the normal full flow rate and note when the compartment is empty. There are several
methods for determining that the compartment is empty. There may be a significant change in
the sound of the pump. There may be visual evidence that the compartment has run dry. The
meter register may stop entirely or may begin to register sporadically (pause, resume running,
pause, run again, etc.)
2) If the meter stops for 10 seconds or more, proceed to step 3. If the meter indication fails to
stop entirely for a period of 10 seconds, continue to operate the system for 3 minutes.
3) Close the valve from the empty compartment, and if top filling, close the nozzle or valve at
the end of the delivery hose. Open the valve from another compartment containing the same
product. Carefully open the valve at the end of the delivery hose to avoid product splashing out
of the prover due to pockets of vapor or air. The test results may be invalid if product is splashed
out of prover.
4) Continue the delivery of product at the normal full flow rate until the liquid level in the power
reaches the nominal capacity of the prover.
5) Close the delivery nozzle or valve. Stop the meter. Allow any foam to settle, then read the
prover sight gauge as quickly as is practical.
6) Compare the meter indication with the actual delivered volume in the prover.
7. Calculate the meter error, apply Product Depletion test tolerance, and determine whether or
not the meter error is acceptable. For NIST Handbook 44 applications, the Special Test
tolerance is applied.

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Single Compartment Test Procedure:
The test of single-compartment tanks is easier to accomplish if there is a quick-connect hose
coupling between the compartment valve and the pump that supplies product to the meter. If the
system does not have quick-connect couplings between the compartment and the meter, an
additional source of sufficient product at the test site is required.
Without a quick-connect coupling:
1) Begin the test with the tank containing an amount of fuel equal to or less than one-half the
nominal capacity of the prover being used. Operate the meter at the normal full flow rate and
note when the tank is empty. There are several methods for determining that the tank is empty.
There may be significant change in the sound of the pump. There may be visual evidence that
the tank has run dry. The meter register may stop entirely or may begin to register sporadically
(pause, resume running, pause, run again, etc.)
2) If the meter stops for 10 seconds or more, proceed to step 3. If the meter indication fails to
stop entirely for a period of 10 seconds, continue to operate the system for 3 minutes.
3) Close the tank valve, and if top filling, close the nozzle or valve at the end of the delivery
hose. Stop the pump and load sufficient product from the alternate source into the supply tank.
Allow the product to stand in the compartment for a brief time to allow entrained vapor or air to
escape. Carefully open the valve at the end of the delivery hose to avoid product splashing out
of the prover due to pockets of vapor or air. The test results may be invalid if product is splashed
out of prover.
4) Continue the delivery of product at the normal full flow rate until the liquid level in the power
reaches the nominal capacity of the prover.
5) Close the delivery nozzle or valve. Stop the meter. Allow any foam to settle, then read the
prover sight gauge as quickly as is practical.
6) Compare the meter indication with the actual delivered volume in the prover.
7. Calculate the meter error, apply Product Depletion test tolerance, and determine whether or
not the meter error is acceptable. For NIST Handbook 44 applications, the Special Test
tolerance is applied.