DPT for an Open Tank

Yes, they can be used.

Consider using ultrasonic level measurement also.

For an open tank it is not a DPT but a pressure transmitter.

The one side of the DPT would just be atmospheric pressure.

Hi,

A differential Pressure Transmitter is a good choice for measuring the level of an open tank . connect the high side to the tank and vent out the low side to atmosphere.If the tank has solids or heavy sludge then a radar,ultrasonic type transmitter will be better as pwslack suggested.

Thank you

Why a Delta P transmitter when you are not measuring Delta P but rather using the device as a pressure transmitter?

One good reason is that if the liquid level to be measured is relatively small, local barometric pressure changes will introduce an unwanted variable into the measurement system. A differential pressure instrument avoids this issue.

The OP has not given any detail on the tank depth and the material inside it. Without those details, the correct choice of level instrument is largely guesswork.

Offcourse we are measuring delta P ... Low pressure side to be vented to atosmphere but high pressure side to be connceted at dattum level.

Why: if your atmospheric pressure will be vary it will be bring a impact on head of the liquid.Hence your desired level differs and error comes.So we are measuring the atmospheric pressure to nullyfy it from the head effect.

thanks

sudip