Scope
This Guideline provides a method to check that metering related
Smart transmitters are functioning correctly. This is achieved by
applying known inputs to the transmitter and comparing them to
the values displayed on the Smart Communicator, and the
current in the instrument loop. The transmitter configuration of
input range and output parameters must be established or
confirmed, according to manufacturer’s instructions, prior to
commencement.
Frequency 3 months.
Procedure
PREPARATIONS:
If stable process conditions exist, and a manual value can be
input at the flow computer, then this test may be performed
with the metering stream in service. Otherwise ensure that the
meter stream is off-line and out of service.
Give a brief description of the test in the Metering Log Book.
Record the results of this test on the Smart Transmitter
Calibration Test Sheet, attached.
Verify that the certificates for the test equipment are valid.
Check that the test equipment serial numbers and
certification dates are accurately recorded on the test sheet
and correspond with the test equipment used. Ensure the
instrument tag and serial numbers are recorded on the test
sheet.
CALIBRATION EQUIPMENT:
A)
Input Source (Dead Weight Tester or Resistance Box)
B) Digital Multi-meter
C) Smart Communicator
PROCEDURE:
The Smart Transmitter shall be checked using the following
procedure: –
a)
Isolate the transmitter from the process.
b) On pressure devices vent/drain the transmitter by
slowly opening the instrument impulse line fitting(s).
c) Connect the input source to the transmitter.
d) Monitor the current in the instrument loop, at back of
panel in the control room, using the certified digital
Multi-meter and the process variable at the Smart
Communicator.
e) Apply simulated field input to the transmitter at 0% and
100%.
f) Complete the Smart transmitter test sheet. Record the
current at the DMM and the process reading at the
Smart Communicator.
h)
If the calibration check is within tolerance the test is
complete.
i)
If the calibration check is out of tolerance transmitter
adjustment is required.
j) Adjust the zero and span to calibrate the transmitter
then repeat step e).
k) Complete the Smart transmitter test sheet, re-instate
the loop and return to service.
l) On pressure devices check all impulse lines for leaks.
m) Enter details of all tests in the Metering Log Book.
SMART TRANSMITTER TEST SHEET
