Scope
This Guideline provides a method to check that the meter and prover
temperature indicators are functioning correctly. This is achieved by
comparing actual temperatures to the displayed temperatures
Frequency
3 months
Procedure PREPARATIONS:
Ensure that this check is undertaken with product flowing
across the thermo-well. Give a brief description of the test in the
Metering Log Book. Record the results of this test on the
Temperature Indicator 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) Digital Temperature Indicator
PROCEDURE:
The Temperature Indicator shall be checked using the following
procedure: –
a)
Insert the digital thermometer probe in the thermo-well
adjacent to the temperature indicator and allow it to
stabilise for approximately 15 minutes.
b) Simultaneously read the temperature indicated on the
digital thermometer and that shown on the temperature
indicator.
c)
If the two readings are within the required tolerance the
test is complete.
d) Complete the temperature indicator test sheet and return
the temperature indicator to service.
e)
If the two readings are out with tolerance corrective
action is required. It will be necessary to calibrate or
change the temperature indicator.
f) Remove the temperature
indicator and digital
thermometer to the instrument workshop, to perform
temperature tests at two points using an oil or sand filled
temperature bath.
g) Establish steady temperature conditions
in the
temperature bath of approximately 80% full scale of the
temperature indicator under test.
h) Place digital thermometer probe and temperature
indicator under test into the temperature bath and allow
stabilizing for approximately 15 minutes.
i) Using the digital thermometer as the standard compare
the actual temperature with the temperature indicated on
the temperature indicator.
j) Repeat the test at ambient temperature (must be lower
than 20 deg C).
k)
If the calibration check is within tolerance the test is
complete.
l)
If the calibration check is out of tolerance adjust the zero
and span to calibrate the indicator then repeat steps g)
to j).
m) Complete the temperature indicator test sheet and return
the temperature indicator to service.
n) Enter details of all tests in the Metering Log Book.
TEMPERATURE INDICATOR CALIBRATION TEST SHEET
