level measurement instrument


Thread Starter


We are expanding our distillation plant. During automation we required some level measurement instrument which can work under high vacuum(1torr) & temperature about 250 Deg. centigrade.
Can any one help me out type of instrument to be use for this application.
If any one has details about Radar type then please give me the details.

Ramesh B. Parmar

We build a custom RVI (remote visual indication) or magnetic flag indication. It are cost effective and with a magnetically coupled reading – nothing will leak if the glass is broken.

A 2” 316 SS stand off tube is built to bolt to the side of your tank. It can be a flange or union. The bottom usually has a 2” fitting but can be a flange – the top has a vent plug.

The liquid in the tube follows the level in the tank. In the tube is a float with a magnetic - the magnet flips the external flags as the liquid changes level. The flags are magnetically coupled as well making it easy to read the level.

To get more than a visual reading you can have: continuous resistive or 4-20, latching adjustable SPDT switch points, or adjustable standard SPST or SPDT switches.

For controllers – you can use your own – or we have latching relays for pump controls, a programmable device with 4 relays a bar graph and 3-digit % indication.

Rating 400 Deg. C

You can see a basic picture and contact us at: http://www.almegcontrols.com/rvi_magnetic.htm

Thanks Bob Hogg

Displacer type level instruments are very popular for such applications. Chemtrols is one known source.

I do agree with Anand that displacer type LT's do function well under such applications, we are using them. But if u are using chemtrols be careful about one thing that they tend to stall at full output. In our applications sometimes that level is 100% and remains there for sometime. We have to toggle the powersupply of the tx to remove the stalling.

I have worked in a desalination plant, there we have an evoporator, wherein we are required to measure the level of the last stage. previously we were using a dP transmitter to measure the level under full vaccum. We always had the problem with it. We opt displacer type make: magentrol, now it is working smoothly.