Please enable JavaScript.
Coggle requires JavaScript to display documents.
MEASUREMENT OF LIQUID LEVEL, automatic level control system, MUHAMMAD AFIQ…
MEASUREMENT OF LIQUID LEVEL
what is liquid level measurement?
to measure the quantity of liquid held in a container or vessel
types of liquid level measurement
direct
indirect
DIRECT
method which the actual liquid level is directly indicated by a simple mechanical type of device.
examples
dip stick method
determining the liquid level by dipping a graduated rod in a liquid
low cost
drawback
not accurate
application
level of oil car engine
sight glass method
determining the liquid level by a graduated glass tube mounted on the side of the liquid containing vessel for providing a visual indication of the liquid level
simple and direct
drawback
-manually recording needed
not suitable for dirty
hook gauge
determining the liquid level is a large tank for accurate measure of a very small change. a small change in a large tank would mean large volumetric changes
accuracy up to +- 0.1mm
drawback
manually operated and no automatic reading
float gauge method
determining the liquid level that always follow the varying liquid level. the float usually used are hollow metal spheres,cylindrical ceramic float.
advantages
capable of giving continuous,direct liquid level measurement
drawback
proper correction is required
INDIRECT
The indirect method of level measurement involves converting readouts and data of a known quantity, such as pressure ratio to the volume.
examples
ultrasonic level sensor
used for non-contact level sensing of highly viscous liquid
requires high degree of experience and skill to operate since the actual instrument is expensive
hydrostatic pressure level measurement
Hydrostatic level measurement is a really simple and reliable method of measuring level. A submersible pressure transmitter or a standard pressure transmitter is lowered to or mounted at a specific depth (zero level). The transmitter then measures the pressure caused by the weight of the liquid directly on top of it
created by a liquid is directly related to the height of the liquid column (p=pgh)
a pressure gauge is installed at the bottom or on the side of the tank
automatic level control system
to provide automatic control, thus machine ,electronic or computer replace the operation of the human
a sensor added that is able to measure the value of the level
MUHAMMAD AFIQ IKHWAN BIN RASHID
(2018291594)
EM 110 4A
