· Pressure calibrator,
· Hart communicator
Procedure of DP Level Transmitter Calibration at field:
· Man placed the computer in the control circuit manual mode and placed it on the ESD circuit MOS.
· Refer to the datasheet to hook up HART 1 Communicator and check some parameters. Typical parameters are PV, LRV and URV tag amount.
· Isolate from the method of the tool.
· Release both pressure and drain low and high side liquid throughout the manifold drain.
· Open both plugs at seal pot.
· Top up seal liquid for the low side until half of the seal pot.
· Remove tubing at the high side of the manifold.
· Hook up the calibrator on the at high side and isolate the vent valve
· To evaluate the present signal, hook up a multimeter in sequence with the signal to the DCS.
· If the amount equal to zero is applied as per calculation, the multimeter should display 4mA.
· If not, use HART Communicator to adjust zero at the transmitter
· Apply pressure according to the calculation if the amount is equal to 100%, the multimeter should show 20mA.
· If not, use HART Communicator to adjust the receiver
· After finishing the task, request the board driver to return loops to normal mode or to normalize the MOS.
· Fill out and submit the calibration form for future reference.