Calibrating the Rosemount Model 1151 Pressure Transmitter is simple and easy. With the aid of an accurate pressure source, an output meter, a power source and external span and zero buttons on the transmitter, the device can easily be calibrated. The zero and span adjustment screws are accessible externally behind the nameplate on the terminal side of the electronics housing. To calibrate the transmitter, setup the equipment required - pressure source, Rosemount 1151 pressure transmitter, Current meter to measure current output from transmitter, power source, pressure gauge (covering the LRV and URV of transmitter), a 250 ohm resistor if necessary for communication with transmitter - as shown below:

The output of the transmitter increases with clock wise rotation of the adjustment screws. The zero adjustment screw does not affect the span. However, span adjustment does affect zero. If you still have this device in your plant, then proceed as below to calibrate the device. You might want to read how to calibrate your Rosemount DP Transmitter before proceeding:

Step 1

Apply 4mA point pressure and turn zero screw to output 4mA output

Step 2

Apply 20mA point pressure. Note actual output in mA

Step 3

Subtract actual output from the desired output of 20mA

Step 4

Divide the difference by 3

Step 5

Turn the span screw above or below the desired output by the value obtained in step 4 above.

Step 6

Repeat steps 1 through 5 until device is calibrated. Transmitter is said to be calibrated if full scale output is 20±0.032mA