Drivers who hold cylinders and record the scans that bill them form one of two circled overlaps on this AC550 Unit 3 system flowchart for a gas supplier. Searches like "ac 550 unit 3 assignment example", "ac550 unit 3 sample" and "ac550 unit 3 example" land here.
What a finished AC550 Unit 3 system flowchart looks like
Two pages of chart and one page of notes. Columns run left to right: Customer, Customer Service, Dispatch, Driver and Handheld, Scan Database, Counter, and Billing System, with the controller's month-end review in a narrow band along the foot. Paragraph numbers from the Unit 2 narrative sit beside every symbol. The nightly 2 a.m. transfer from scan database to billing appears as a single processing symbol with a clock annotation, feeding the customer balance file. In the margin beside each symbol a letter, A, R or C, marks authorization, recording or custody. Two red circles flag where one role holds two letters: a driver who carries cylinders and records the scans that set balances, and a branch manager who approves rent waivers and edits the spreadsheet billing reads.
How a AC550 Unit 3 example is structured
The chart borrows the narrative's numbering, so every symbol cites a paragraph and every paragraph appears as at least one symbol; the notes page lists the three paragraphs drawn as combined steps. Columns follow responsibility, with the two databases given columns of their own because they act without a person present. The batch transfer is drawn as one step with its input file, its output file and its schedule stated, since later units center on it. Margin letters are the chart's analytical layer, turning a picture of flow into a map of who approves, who enters and who physically holds the asset. The notes explain each red circle in two sentences, one describing the overlap and one naming what it allows, and they propose no remedy at this stage.
Seven columns and a foot band
Five human roles and two databases across the page, with the controller's monthly review drawn along the bottom because it touches every column once a month.
Paragraph numbers on every symbol
Each shape carries the Unit 2 paragraph it depicts, and the notes list the three places where two paragraphs were drawn as one step, with the reason.
The 2 a.m. transfer
One processing symbol, its input scan file and its output balance file, labeled with the time it runs. Anything scanned after the trucks return waits until the next night.
A, R and C in the margin
Authorization for credit holds and waivers, recording for scans, keying and posting, custody for cylinders on trucks and in the yard, marked step by step.
Two red circles
The driver holds custody and records the scan that sets a balance; the branch manager approves a waiver and edits the file billing reads. Each overlap gets two sentences.
Where marks go in AC550 Unit 3
Separation of duties drawn nowhere on the chart is the gap graders notice first, since the prompt in this unit usually names it, and a tidy diagram without a view of who approves, enters and holds assets misses the assignment. Chart and narrative are compared line by line; a step on one that the other omits suggests two separate efforts. Automated steps drawn as though a person performed them hide the batch job that makes balances stale, and a batch step shown with no schedule or files hides it just as well. Smaller deductions follow inconsistent symbols or a key contradicting what is drawn. Fixes written onto the chart itself blur description with evaluation. Overlaps circled without a sentence explaining what each one allows earn only partial credit.
Get a AC550 Unit 3 example written to your instructions
A Unit 2 narrative, or any narrative the Unit 3 case hands out, gets the chart started; include the rubric plus whichever notation and software the instructor names. Charts come back in 24-48h with separation of duties marked on them, and the first custom sample is free.
AC550 Unit 3 questions, answered
What do authorization, recording and custody mean on a flowchart?
They are the three functions a sound design keeps in different hands: approving a transaction, entering it in the records, and physically holding the asset it concerns. When one person can do two of them, an error or a theft can be both committed and concealed. The chart marks each step with its function so any overlap is visible at a glance.
Should databases get their own columns?
Where they act without a person, yes, in most AC550 conventions. The Halvorsen chart gives the scan database and the billing system separate columns because the nightly transfer between them runs unattended, and that transfer is where later analysis focuses. A database folded into a human column makes automated steps look like somebody's decision.
How is an overlap shown if the notation has no symbol for it?
With an annotation and a legend entry. The sample uses margin letters and a red circle, both explained in the key, which keeps the standard symbols untouched. Some instructors prefer a separate table beside the chart listing each role's functions; either approach is acceptable when the overlap is visible and explained in writing.