DP Level Transmitter

Try calling the supplier or a distributor of Rosemount products. They will be happy to help.

Dipstick.

Would that be in reference to the OP, or your recommendation of a calibration instrument?

Google: rosemount model 3051

For open tank with transmitter mounted at same height as the tapping;

1. Ensure that the low pressure side of the transmitter is vented;

2. 0% = 0 inches WC (assuming that 0% level is specified as the height or level of the tapping.

3. 100% = (specified height or level in the tank corresponding to 100% X SG of the liquid in the tank) inches WC.

For open tank with transmitter mounted below the tapping (wet leg);

1. Ensure that the low pressure side is vented.

2. 0% = (distance from the transmitter high pressure connection to the specified height or level corresponding to 0% X SG of the liquid in the tank) inches WC.

3. 100% = (distance from the transmitter high pressure connection to the specified height or level corresponding to 100% X SG of the liquid in the tank) inches WC.

For closed tanks;

1. ensure that the low pressure side of the transmitter is connected to the top of the tank.

2. Calculation of the ranges will be the same as above since the vapour pressure above the liquid interface will impact on both the high pressure and low pressure sides and therefore will be cancelled out.

For closed vessels in which filling of both legs is inevitable such as steam drums (due to condensate);

1. 0% = pressure exerted on the high side with liquid level at specified low level - the pressure exerted on the low side with impulse tubing filled with liquid. (This will result in a -ve pressure).

2. 100% = pressure exerted on the high side with liquid level at specified high level - the pressure exerted on the low side with impulse tubing filled with liquid. (This will also be a -ve pressure or zero if the 100% level is specified as the height of the low side tapping, which is usually the case.)

Note; pressure exerted by the liquid (hydrostatic head)=liquid height X liquid SG.

thanks for the reply to ur msg for the level transmitter,but to clarify my doubts if the transmitter is calibrated for eg -30kpa to -60kpa where the milliamps is 4-20 ,without the impulse line .Now if the impulse line is filled with glycerine it is obvisious that there would b pressure acting on it , is that the glycerine that is filled should b filled in such a way that the transmitter should read 4 ma (linearmode),if i have to chk zero on line how do i chk ,do i have to open the equalizer or any other method for level only