location of DP level transmitter

Hi there,

Ideally you would want to mount the transmitter at the lower level elevation. If this is not possible you can mount it below this point - the important thing to bear in mind is the height as this is part of the equation that you use to get the level. i.e. pressure = height x density x gravity. So by this you will have to take the extra height into consideration.

I would also consider a wet leg installation - depending on your process medium and mechanical setup.

Regards,

Craig

thank for your information. I forget to let you know that I am using wet reference leg DP level transmitter for closed tank. So if I mount the transmitter 2-3m below the lower level elevation how does it affact to level in the reference legs when temperature change?. Thank you.

if both legs comes down with same length than the head gets balance provided hp leg has to be filled with liquid,what is filled on wet leg ,generally HP tapping is near to the nozzle .it depend on the access you need for maintenance .

Hi there,

I would only worry about the temperature change if your ambient temperature is a huge difference from the medium inside the tank. Obviously the temperature difference will affect the density - but the error is not that big, especially if your tank is quite large and you do not require 100% accuracy.

If you were measuring on a steam drum level for example then I would do things a bit differently as you need to compensate for this temperature change as well as the pressure fluctuations within the drum.

I have posted a solution for this in this forum - just have a look to see if the solution applies to what you want to do.

Regards

Craig

hello

You can fill the wet leg with water (or mixed with glycerine). It doesn't matter where your dp is locating (i mean under the hp - receipt or at the same level). you can take 4mA(calibrate) with filled the wet leg. So the dp has to be at an accessible point.