Franklin Fueling Systems T5 Series Fuel Management System Operators Guide - Manual (Page 16)

12
Tank Testing
Why Test the Integrity of a Tank
In compliance with federal, state and local regulatory policies, all tanks must be monitored for leaks due to environmental
and public safety/health concerns. Tank tightness testing determines if there is a leak.
There are two types of Tank Testing available in the Fuel Management Systems: Static and SCALD.
SCALD Testing
Static tests are run during quiet times when the tank is thermally stable and the site is closed so that no dispensing or
deliveries will occur. There are two types of Static tests: Monthly (0.2 gph) and Annual (0.1 gph). Static tests can be
scheduled to run on a Daily, Weekly or Monthly basis in the Setup menu (Administrator use only). They can also be
started on demand from the FMS > Control menu. Make sure that all testing conditions are met before starting a Static
Tank Test.
SCALD (Statistical Continuous Automatic Leak Detection) tests run 24 hours a day and look for periods of quiet time when
the tank is thermally stable and no dispensing or deliveries are occurring. These quiet periods are collected and analyzed
and the tightness of the tank is determined. SCALD tests will update whenever possible and can be setup to print
automatically when they do. The more common method is to schedule the latest SCALD test to print out once a week,
saving a significant amount of paper because SCALD tests can be generated multiple times a day on a quiet tank.
Static and SCALD tests run independently of each other and can be run at the same time. A SCALD test will likely
complete during the time that the Static test is running. See page 15 for further SCALD information.
Tank Pre-qualification for SCALD
It is important to pre-qualify a site before making the decision to order the SCALD software. A site not meeting the
following parameters would not be able to use SCALD.
For a tank or manifold (two connected tanks) to routinely complete SCALD tests, there must be an average of at least:
• 4 Quiet Intervals (QIs) lasting an average of 20 minutes when no dispensing occurs from the tank or manifold. The data
collected during these QIs, must be thermally stable. Tanks that receive frequent deliveries, especially where there are
large differences in temperature between the fuel coming off the truck and the fuel in the ground, will have a hard time
collecting enough QIs to get a completed SCALD test.
• 48 hours between deliveries to that tank or manifold. This time period may need to be extended to 72 hours in areas
that experience periods of extreme temperatures.
Sites that barely qualify under both instances above may still experience periods where SCALD is unable to collect QIs
because of thermal instability. Rescheduling the deliveries to the tank(s) may improve the generation of QIs. Filling a tank
as full as possible in the morning and allowing as many nights, when most QIs occur, as possible to elapse before filling
the tank again, will improve the chances of completing a SCALD test.
All FFS Fuel Management Systems meet the requirements of the U.S. Environmental Protection Agency (EPA/530/UST-
90/006 test protocol) for Automatic Tank Gauging Systems (ATGS). The system(s) also meet the requirements for Annual
Tank Tightness Testing for 0.1 gal/hr leaks of the National Work Group on Leak Detection Evaluations (NWGLDE). Third
Party Testing Laboratory test results (for standard static tank leak tests) are also available at http://nwglde.org/ .
Static Testing
Terms
Threshold – Test results must be within these programmable limits to pass a leak test. There are Monthly, Annual and
Sentinel Mode Thresholds.
Sentinel Mode – Sentinel mode is designed to monitor the product levels in your tank(s) when there isn’t supposed to be
any dispensing.
Confidence – Level of testing sensitivity indicating the probability that the test will detect a leak.
Higher confidence percentages will produce more sensitive test results. Check local regulations to
verify acceptable confidence levels.
Flow
Time No Leak
(+) slope
(–) slope
Slope (Tank Testing Reports) – A ratio of the calculated rate of change to the time the rate is
measured. Slope is affected by leaks and by many other sources of interference. A negative slope
or decrease indicates loss of product volume. A positive slope or increase indicates a rise in product
volume.