Dresser Model 10C25 Series K Installation, Operation, and Maintenance Manual
© 2018 Natural Gas Solutions North America, LLC
Page 60 of 74
3.
Use a magnet to scroll the
meter’s
LCD screen to
FLOW RATE
. After approximately five (5) seconds,
the screen will display the calculated flow rate. Convert the calculated flow rate to a percentage of
meter rated capacity by using the following formula:
% 𝑀𝑒𝑡𝑒𝑟 𝐶𝑎𝑝𝑎𝑐𝑖𝑡𝑦 =
𝐹𝐿𝑂𝑊 𝑅𝐴𝑇𝐸 × 100
(𝐵𝑎𝑠𝑒 𝑅𝑎𝑡𝑖𝑛𝑔)
Note:
The base rating is determined by using the meter rating of 1000 acfh.
4.
Record the pressure differential, line pressure, and gas specific gravity. Repeat the test to obtain an
accurate average reading.
Note:
At the time of meter startup in a new installation, repeat Steps 2
4 at a minimum of
three (3) different flow rates, each between 25% and 100% of meter capacity. An original
baseline curve should be drawn using data at a constant pressure for all three (3) tests.
5.
Remove the differential test equipment.
6.
Perform one of the following steps:
•
If this test is for the baseline curve, plot and save the curve for future reference.
•
If this is a subsequent test and the pressure differential compares against the baseline curve
within acceptable limits, return the meter to full service.
•
If the pressure differential is not within acceptable limits or has increased by 50% above the
values on the baseline curve, remove the meter for inspection and, if needed, for service.
14.2.3
Periodic Differential Testing
After developing a baseline curve, check the meter condition and performance periodically by running a
similar differential rate test at a single selected point.
If the differential pressure increases by more than 50% above the original value, inspect the meter for
causes for resistance. The usual causes are binding impellers, worn bearings, or contaminants (such as dirt
or valve grease) in the metering chamber.
14.2.4
Repair Information
For Factory repairs and/or inspection, please call your Customer Service Representative or your Dresser
meter supplier to request an RMA (Return Material Authorization). For more information, refer to Section
5.
