Issue
Date: August 23, 1999
Revision Date: June 24, 2002
Veeder-Root
(originally
listed as Gilbarco Environmental Products and later as Marconi
Commerce Systems)
EMC/PC
Series Monitoring Systems
PA0265 (Same as Veeder-Root Model 8473),
PA0300 (Same as Veeder-Root Model 8473)
(Magnetostrictive Probe)
AUTOMATIC
TANK GAUGING METHOD
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Certification
|
Leak
rate of 0.2 gph with PD = 99.5% and PFA = 1.6%.
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Leak
Threshold
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0.126
gph.
A tank system should not be declared tight if the test
result indicates a loss or gain that equals or exceeds
this threshold.
|
|
Applicability
|
Gasoline,
diesel, aviation fuel.
Other liquids with known coefficients of expansion and
density may be tested after consultation with the manufacturer.
|
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Tank
Capacity
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Maximum
of 20,000 gallons.
Tanks less than 95% full may be tested.
Minimum product level required is based on tank diameter
as follows:
48" dia/min 18";
64" dia/min 21";
72" dia/min 24";
96" dia/min 30";
126" dia/min 39";
132" dia/min 39".
For other tank diameters see evaluation report.
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Waiting
Time
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Minimum
of 8 hours between delivery and testing.
Minimum of 30 minutes between dispensing and testing.
There must be no delivery during waiting time.
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Test
Period
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Minimum
of 2 hours.
Test data are acquired and recorded by system's computer.
Leak rate is calculated from the difference between the
first and last data collected.
There must be no dispensing or delivery during test.
|
|
Temperature
|
Average
for product is determined by probe which contains 5 thermistors.
At least two thermistors must be submerged in product
during test.
|
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Water
Sensor
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Must
be used to detect water ingress.
Minimum detectable water level in the tank is 0.66 inch.
System is programmed to report water depth only when it
exceeds 0.75 inch.
Minimum detectable change in water level is 0.005 inch.
|
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Calibration
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Thermistors
and probe must be checked and, if necessary, calibrated
in accordance with manufacturer's instructions.
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Comments
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Not
evaluated using manifolded tank systems. Therefore,
this certification is only applicable when there is
a probe used in each tank and the siphon is broken during
testing.
Tests only portion of tank containing product. As product
level is lowered, leak rate in a leaking tank decreases
(due to lower head pressure).
Consistent testing at low levels could allow a leak
to remain undetected.
EPA leak detection regulations require testing of the
portion of the tank which routinely contains product.
California regulations
require at least one test per month after routine product
delivery or when the tank is filled to within 10% of
the highest operating level of previous month.
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