A throw-in type level transmitter, also known as hydrostatic pressure level sensor, is an extension of advanced pressure transmitter technology for different applications. It can be used to measure height and pressure of water in water tanks, oil, and low-concentrated testing media. It receives different pressures at different depths of liquid, which can be converted into corresponding current signals and output through the sensor. The shell of the transmitter is made of stainless steel which is anti-corrosive and easy to clean. It can be directly placed in liquids like water, oil or even mash with large viscosity. So, how is a throw-in type level transmitter chosen and installed? This blog will look to provide answers in this regard.
Benefits and Applications
A throw-in type level transmitter features high precision and great stability, simple and convenient installation where it can be directly put into testing medium, integrated structure without any separable parts, highly reliable and long service life, wide range of temperature compensation with test results unaffected by changes in the testing medium and power reverse polarity protection and overload current limiting protection.
The throw-in type liquid level transmitter can be used in waterworks, refinery, sewage disposal work, construction, light industry, mechanical engineering etc. Differential pressure level transmitters are often required in pharmaceutical, food, beverage, and petrochemical industry processes. They are installed at the bottom of the liquid tank and gauge pressure reflects liquid level. In these processes, tanks are often under pressure where throw-in type level transmitters are not able to work.
Factors to Consider
Many factors need to be taken into consideration when choosing the most suitable throw-in type level transmitter for an application. Particular attention needs to be given to the following:
- Confirm testing medium and its nature, e.g., corrosiveness, thickness, particle content, etc. For example, an anti-corrosion liquid level transmitter can be used in a medium with high corrosiveness and a capacitance liquid level transmitter can be used to test media with high solid-particle content.
- Understand the output signal needed for the application. The output signal needs to match the input signal of PLC, DCS or devices from the whole system. Common output signals are 4-20mA, 0-20mA, 1-5V, 0-10V and other digital signals.
- Check the available power supply or power input for the level transmitter. The most common power supplies are 24Vdc and 220Vac. Special voltage according to different geographical locations are 12Vdc, 15Vdc, 48Vdc and 110Vac.
- Know the process connection type and size; liquid level transmitters are generally installed by screw or flange installation.
- Consider the level of accuracy needed for the application; standard accuracy can be used in applications with no special requirement.
- Working environment is also an important effect. Anti-explosion level transmitters are required to be used in power plants such as Mitsubishi Power. In chemical plants, anti-corrosion is also a required feature for instruments.
As can be observed, while the throw-in type liquid level transmitter can play an important role in the measurement of liquid depth, it is a sensitive tool which needs to have settings incorporated during the structural steel fabrication proces. This product can provide a steady performance in all sorts of measurement conditions such as river, reservoir, city water supply, etc. and the design of this type of transmitter is based on the linear relationship between the measured hydrostatic pressure and the height of the liquid. Thus, knowing where and how to use the throw-in type level transmitter is important as the calibrations will reflect the findings!