OPW M2010-EU, Installation Manual

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5.2 Product Offset Calculation
It is possible to calculate product offset for a probe that is not installed in the center of a "pitched" tank. Pitch
occurs when a tank is installed tilted along its horizontal axis. Some tanks are installed with one end lower
than the other to let water and sediment collect at the low end, so that clear product can be pulled from the
high end. Tank "settling" can also occur and can cause a tank a tank to become tilted. Use a dipstick to
measure the level of product at two points of the tank. It is recommended that these measurements be taken
at opposite ends of the tank (see the figure below).
The product depth at the lower end of the tank is value “A.” The product depth at the higher end is value “B.”
The distance between the two measuring points is “C.”
The formula for pitch is:
(A-B)/C
For example:
(46"-40")/120" = 6"/120" = 0.05”
To calculate the product offset, measure value “D,” the distance of the probe from the center of the tank. The
formula for product offset is
“D” x pitch
. For the example above: 36” x 0.05 = 1.8”.
If the probe is located closer to the higher end of the tank, the product offset is positive. For the example
above: 1.8”.
If the probe is located closer to the lower end of the tank, the product offset is negative; for the example
above: -1.8”.
Product Offset
Doc. No.: M2010-EU Rev.: 13
Page 35 of 149