Section V – Factor Optimizing
MN06146 Issue/Rev. 0.1 (7/10)
8
Start at Q
1
, the Maximum Flow Rate. Use the Input
Resolution Setting and Factor Setting determined
previously. Use Smith Form “Meter Proving Report,”
which is Appendix A of this manual, or an equivalent
form to record all data.
Note: The term “Factor” in this section refers to the Calibration
Factor if used with an AccuLoad II or AccuLoad III.
Step 1
Reprogram the AccuLoad as follows to obtain the fac-
tor at Q
1
:
1.
Set the Minimum Flow Rate.
2.
Set the Low Flow Start to “yes.”
3.
Set the Low Flow Start Volume at about 5% of
the tank prover volume (to reduce splashing on
start-up).
4.
Set the Low Flow Start Rate at about 0.5 times Q
1
value.
5.
Set the High Flow Rate.
6.
Check that the flow tolerance is in proper range,
typically 5% to 9%.
7.
Set the First Trip Volume at a minimum value,
typically 5% to 8% of Q
1
. Example: For Q
1
of 500
gpm, set at 25 to 40. Reset later to normal opera-
tion when final proving in Step 23.
8.
Check the Final Trip Volume. Set to 1.5 (reset
later when final proving in Step 23).
9.
Set the Input Resolution to the Input Resolution
Setting determined above.
10.
Set Flow Rate Number 1 to zero (0000). Set Fac-
tor Number 1 to the Factor Setting previously de-
termined.
11.
Set Proving Mode Select to W&M Proving.
Step 2
Start proving runs.
1.
Return to Run Mode.
2.
If a First/Second High Flow Switch is used, make
certain the switch is in First High Flow Position
(Q
1
).
3.
Preset Tank Prover Volume.
4.
Press “Start” to fill prover.
Step 3
Wet down the prover and stabilize the temperature of
the meter/prover system. Fill and drain the prover
once or twice until the measured liquid temperatures
at meter and prover are equal within 1
°
to 2
°
F. Also,
confirm that excessive splashing or foaming does not
occur at this high flow rate. If it does, reduce the flow
rate and/or increase the duration of the brief low flow
start to the minimum amount needed to eliminate the
problem.
Note: Typically after each proving run, before closing the prover
drain valve, allow the prover to drain down for exactly 30 seconds
after solid flow has broken to maintain a consistent “clingage vo-
lume” in the prover.
Step 4
Now start an additional proving run to determine the
meter factor. Determine the meter factor (MF) at Q
1
.
The meter factor is determined from the actual tank
prover reading and the AccuLoad volume registered.
Volume
Registered
Volume
Prover
Tank
Actual
MF
Example: 1,000 gallon tank prover
Actual Tank Reading: 999.65 gallons
AccuLoad Reading: 999.9 gallons
9997
.
0
9
.
999
65
.
999
MF
Note: Typically, tank provers read in ± cubic inches, one gallon =
231 cubic inches.
Step 5
Check the repeatability of MF at Q
1
. Make one to four
repeat runs to determine:
1.
Repeatability
2.
Average Meter Factor (MF)
Example: MF = 0.9997
0.9998
0.9996
0.9997
Average MF = 0.9997
Step 6 (AccuLoad I Only)
Compute and enter the new Calibration Factor (CF)
at Q
1
:
Summary of Contents for Smith Meter AccuLoad
Page 4: ......
Page 18: ...Section VII Appendix MN06146 Issue Rev 0 1 7 10 14 ...
