TLS Console Setup for MAG-XL Flex Probe
TLS Limit Calculations
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TLS Limit Calculations
To calculate the gallons per inch (GPI) for each tank, install the MAG-XL Flex Probe and call for a delivery. Record
the current fuel height at the TLS, make the delivery and after waiting a few minutes for the tank level to stabilize
take a second fuel height measurement. Divide the delivered volume in gallons by the recorded fuel height change
in inches to get your tank’s gallons per inch value.
LIMIT CALCULATION EXAMPLE
1.
Fuel height reading before the delivery = 48 inches. Fuel height reading after the delivery = 72 inches
2.
Ticketed delivered fuel amount was 6050 gallons.
3.
Difference in fuel height recordings = 24 inches.
4.
Divide the delivered fuel volume by the fuel height change = 6050/24 = 252.08 gallons per inch (GPI).
5.
If the tank is 30 feet high, then 30 x 12 inches per foot = 360 (the tank’s height in inches) then the 30-foot
tank’s full volume would be 252.083 GPI x 360 inches = 90750 gallons.
6.
Also, if applicable, you must consider the 12” null zone at the top of the probe. If the probe riser pipe is longer
than 9 inches, the null zone can be ignored. If the probe riser is 9 inches or less subtract the riser length from
12” to calculate the non-working top section of the probe. For example, you have a 5-inch riser: 12” – 5” = 7”
and 7” X 252.08 gallons is 1765 gallons that cannot be measured by the MAG-XL Flex Probe. This reduces
the 100% or full volume to: 90,750 – 1765 = 88,985 gallons.
7.
To calculate the various alarm limits using the above example 30 foot tank having a 5-inch riser and a dis-
charge port that is 24 inches from the bottom of the tank (ref Figure ):
• 100%
88,895 gallons
Full Volume
• 95%
84,450 gallons
High Product
• 90%
80,005 gallons
Overfill Limit
• 20%
17,779 gallons
Delivery Limit
• 10%
8889 gallons
Low Product
• Minimum Volume is the volume that is below the bottom of the discharge port (calculated by multiplying
the distance from the tank bottom to the bottom of the discharge port by the GPI. In this example, 24” X
252.08 GAL. = 6050 gallons).
