Question

Liquid level varies from empty (same height as DP Cell) and 8m (same height as wet leg connection), Specific Gravity of the liquid is 1.5. You want an output of 4mA when the tank is empty and 20mA when full. The pressure inside the tank is 150Kpaa. The calibration of the DP Cell should be:

Consider the image, where the DP cell is being used to measure level: Fill Connection Maximum Detectable Level Reference Leg Liquid Minimum Detectable Level DP Cell) and Bm (same height as wet leg connection), Specific Gravity of the liquid is 1. Liquid level varies from empty (same height You want an output of 4mA when the tank is empty and 20mA when full. The pressure inside the tank is 150Kpaa. The calibration of the DP Cell should be

Answer 1

Calibration of DP cell: - Pressure = density times g times Height At 4m A output of the liquid level should be zero. Pressure = 0 (because Height = 0). At 20 m A the liquid level should be full i.e., equal to 8m So, pressure = 150 Kp_a.