Levelcom 100 - Specific Gravity; Tank Table

To Next Page

To Previous Page

Page 66

(Select one in each category. Select Ullage if desired)

Depth Units: Inches___ Feet___ Feet and Inches___ Centimeters___ Meters___

Ullage___

Volume Units: Not Used___ Gallons___ K Gallons___ Liters___ K Liter___

Ullage___

Weight Units: Not Used___ Short Tons___ Long Tons___ Metric Tons___

Ullage___

Display Units: Depth___ Volume___ Weight___

Specific Gravity: ____________

Specific Gravity

For programming purposes, it is important to use the specific gravity value that was used to

establish the sounding or tank data from which the Tank Table data was derived. The

specific gravity can be adjusted to the present (or future) contents of the tank after

programming is complete. With each update of specific gravity, the LevelCom 100 will

recalculate the Tank Table level and weight data and correct the display accordingly.

Tank Table

This programming section defines the physical properties of the tank. Use caution when

gathering the data for the Tank Table. Remember that the LevelCom 100 (and any other

pressure based level indicator) measures the vertical pressure of a liquid column. Because

of angularity of sounding tubes and the location of the sounding port, sounding tables are

often not true vertical representations of the tank’s depth to volume characteristics. On

some ships, we have seen instances where the sounding tables indicate depths greater than

the actual depth of the vessel itself. The Tank Capacity Curves, ullage tables or other

engineering data are sources for the vertical data required. As a last resort, the data may be

found on the scales of the old tank level indicators; however, in most instances the LevelCom

100 is much more accurate than “eyeballing” the scales.

If the depth is the only parameter to be displayed, then you need only program Maximum

Depth and Bubbler to Bottom. However, if the tank is non-linear (the cross section changes

with depth) and volume and/or weight is to be displayed, then the Tank Table must be

programmed.

The multiple levels (Max Depth and D9-D1) in the Tank Table are used to define the depth to

volume/weight curve for non-linear tanks. To maximize accuracy of the instrument we

recommend a graph of the depth to volume curve be created using Excel, Lotus, etc.

Beginning at the top of the tank and working downward, set Tank Table points along the