Description: Electronics and Fluid Dynamics
The Electronic Water Level is a very basic design consisting of a sealed reservoir which is connected through 100 ft. of 3/16” id tubing filled with fluid connected to a very sensitive pressure gauge . This is all neatly attached to a reel which has nothing to do with the operation of the level and therefore will not be mentioned again.
Regardless of the horizontal distance between the reservoir and display, the display only senses or reads the pressure differential between the reservoir and display. (Which is a linear coefficient of the vertical height differential).
In other words: Regardless of how far apart the reservoir and display are horizontally, the pressure read by the display will always equal the vertical height of the display in relation to the reservoir. If the display is 1 inch higher than the display and 1 mile apart horizontally the display reads the same pressure as if the display were right beside the reservoir and 1 inch higher. 2 inches higher is twice the pressure as 1 inch, 4 inches higher is 4 times the pressure as 1 inch and 4 inches higher is twice the pressure as 2 inches, etc.
The tubing can be raised or lowered, ie looped over chairs- under floors when used underneath the homes in basements-crawl spaces etc., or around and behind objects without affecting the readings. Any increase in pressure by looping over a couch for example, will be exactly offset by the decrease in pressure when the tubing returns to the original plane on the other side of the couch. Only the vertical height difference of the display in relation to the reservoir changes the readings.
The level will read to 100 inches but is most accurate in the +, – 40 inch range. Accuracy is plus or minus 0.1 inch, (1/10 inch) within this range. Large temperature changes will cause slight variations in the readings until the temperature of the level equalizes with the operating environment. Levels are tested at the factory from 70 degrees to an increase of 60 degrees at 130 degrees Fahrenheit and are only allowed to vary 0.2 inch.
- Perform a quick check of zero and scale before starting the elevation survey.
- Perform the elevation survey.
- Perform an ending quick check of zero and scale.
Note: It is recommended to log your quick check of zero and scale before and after each elevation survey in case you are called upon to verify the accuracy of your instrumentation.
- Unwind all tubing and check for air.
- Remove reservoir cover and check fluid level, fill only with the proper fluid.
- Check and set zero & scale. (Quick check is 5.9” ground to side of reel.)
- Maintain log of zero and scale checks before and after each elevation survey.
- Cell phones can cause the display to flicker quickly returning to the original reading.