Scl (Pulser Assembly); Meter Calibration - FILL-RITE TS20A LPG Manual De Instalación Y Funcionamiento

SCL
(Scaler/Calibrator/Linearizer)
Description: Tuthill SCL is a small electronic device de-
signed to provide the function of a pulse Scaler, an electron-
ic Calibrator. This electronics package replaces a mechani-
cal gear plate and mechanical calibrator while at the same
time providing the ability to improve the accuracy of a meter-
ing device during low flow operation, thus improving the
overall meter accuracy, and extending the flow range of the
metering device. The SCL may be used in conjunction with
other Tuthill electronics to solve many of your electronic
interface requirements.
Specifications:

Input Voltage

Input Current

Operating Temperature:
Output:

Quadrature Pulse

Output Voltage

Duty Cycle

Output Frequency

Calibrator Range

Output pulse on-time :
OPERATION:
The SCL may be used to perform a number of functions
depending upon the users application. The following is a
brief description of several of the SCL functions.
CALIBRATOR MODE:
The SCL is equipped with two rotary switches S3 and S4,
and a two position switch S2. The three switches allow the
SCL to adjust the pulse output up or down by 3%.
This allows the operator, or W&M authorities to calibrate the
meter without having to alter scale factors in customer elec-
tronics. This feature is designed to replace mechanical cali-
brators used in the field for years to adjust the meter output
to accurately match the volume in a proving vessel.
The calibrator feature may be used if the SCL in being used
as a scaler only, or as a scaler/linearizer.
SWITCHES:
S1 :
Must always be in set position.
S2 : Is used in conjunction with S3 and S4.
SCL & Pulser Assembly
: 5Vdc and 6 to12 Vdc
: 25ma @ 5Vdc
o
-40 C to +85°C
(U/L T4 upper limit is +40C)
: Proportional to
power supply voltage
: Symmetrical Quadrature
with 50/50 D.C.
: (Input Frequency) X (ECF)
Scaled to application
: +/- 3.0%
Fixed by firmware
If in the minus (-) position, an increase in the S3 and
S4 switch settings will decrease the pulse output. A
decrease in pulse output will increase the volume in
a prover vessel. If in the plus (+) position, an in-
crease in the S3 and S4 will increase the pulse out-
put. An increase in pulse output will decrease the
volume in the prover vessel.
S3/S4 Adjust the SCL pulse output up or down +/-3.0%.
S3 and S4 will allow for 00-99 settings. Each incre-
ment changed in this setting, changes the SCL
pulse output by approximately 0.03%

METER CALIBRATION:


Flow meter re-calibration should be on a volume
equal to 1 minute of flow at maximum flow rate.

All tests should be performed 3 times under identi-
cal conditions to confirm repeatability.

Maintain a permanent file for each flow meter, and
record % change each time the meter is re-
calibrated.
When the change is significantly higher than that
found in previous re-calibrations, it is time to re-
build the flow meter (replace the two oval gears).
METER CALIBRATION:
The calibrator allows you to adjust the output of the SCL up
or down, like a mechanical calibrator, +/- 3% in increments
of 0.03%.

After calibrating a known volume (X) into an accurate
prover (or through a master meter with adequate resolu-
tion), compare with register reading (Y) and calculate
correction:
To reduce the volume in a prover vessel (can), place
switch S2 in the plus(+) position.

Adjust the S3 and S4 to the position required for the
necessary volume reduction in the prover can. Switch
S3 and S4 represent readings of 00 to 99, and each
increment will adjust the output approximately 0.03%.
Example:
Using a 20 gallon (75.7 liter) can, the can reads 113.5
ml high. The meter error is (113.5/75700) = 0.0015
or .15%. To adjust the meter output, place S2 in the
positive position, and set S3 and S4 to read 05. This is
approximately a 0.15% adjustment.
Activate the Reset push button switch to enter the new
program settings. Retest the flow meter.

To increase the volume in the prover vessel. Place
switch S2 in the negative (-) position, and set switches
S3 and S4 to the proper settings to adjust the output.
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