ProSoft Technology PTQ-AFC - Manual (Page 245)

PTQ-AFC ♦ Modicon Quantum Platform Reference
Liquid and Gas Flow Computer for Hydrocarbon Products User Manual
ProSoft Technology, Inc. Page 245 of 259
June 23, 2011
11.9.11 Why does the AFC Manager show a "Communication
Timeout" warning?
The communication parameters for the AFC Manager and the module should
match. Look at the communication parameters and cables (RS-232 null-modem).
Also ensure that the setup jumper on the module is OFF.
11.9.12 What is the difference between Net Accumulator and Gross
Accumulator?
The module initially calculates the Gross Accumulator value. It then uses the
Gross Accumulator value and corrects it for pressure and temperature before
calculating the Gross Standard Accumulator value.
For Gases, Gross Standard Accumulator = Net Accumulator
For Liquids, Gross Standard Accumulator - Water = Net Accumulator
11.9.13 What are the accumulator’s totalizer and residue values?
The totalizer is the integer part and the residue is the fractional part. The
accumulator will be calculated by:
Accumulator = Totalizer + Residue
11.9.14 Do I have to enter all molar concentrations for the gas
product?
Yes, the module uses the Detail Characterization Method that requires all molar
concentration values.
11.9.15 Can I update the molar concentration values dynamically?
Yes, if the values are generated from a gas chromatograph you can update these
values from the processor to the module (via backplane). Refer to the module's
user manual for more information about this subject.
11.9.16 Why do the accumulator values not update?
Follow these steps:
1
Check if the Wallclock is running. The Wallclock should be set every time the
module powers up by ladder logic. If the Wallclock is not running, some very
early versions of the AFC will not perform the applicable calculation.
2 Determine if the meter has an alarm using the Meter Monitor dialog box. If the
alarm field is red, it indicates that the meter has at least one alarm.
3 Determine if the meter is enabled. If the meter is not enabled, it will not
perform the applicable calculation.
4
Look at the input variables in the AFC Manager. Make sure the values that
are being copied from the processor match the input variables displayed at
the AFC Manager Meter Monitor dialog box.