CCST 43 — As-Found / As-Left Tolerance Decision

Briefing

After a calibration check the technician enters the errors as signed hundredths of a percent of span: AS_FOUND_ERR_X100 (the error before touching anything) and AS_LEFT_ERR_X100 (the error after any adjustment). ADJUSTED is on once the technician has adjusted the instrument. The rules for this plant: - As-found tolerance is +/-0.50 percent (50). Outside it, ADJUST_REQUIRED is on. - If the as-found error is in tolerance, the calibration passes: CAL_PASS is on. - If it was out, CAL_PASS comes on only after the instrument has been adjusted AND the as-left error is within the tighter +/-0.25 percent (25). - Each limit includes its edge, and errors can be negative. A comparison cannot be written against a negative number, such as | (A > -5) |. To test a negative reading, flip its sign first with SUB(0, X) and compare the flipped value with a positive limit. Comparisons are built with Compare boxes, or in the Code tab as contacts, for example | (A > B) | := LAMP ;

Objectives

• As-found within +/-0.50 percent: no adjustment needed, calibration passes
• As-found outside +/-0.50 percent, high or low: ADJUST_REQUIRED on
• After an adjustment, CAL_PASS only if the as-left error is within +/-0.25 percent
• An out-of-tolerance instrument never passes without an adjustment

I/O Table

Your program will be tested against:

All test cases run automatically when you submit. Assertions are hidden until you pass.

1. #1As-found +0.20 → passes, no adjustment

   In tolerance when found

2. #2As-found +0.80 → adjust required

   Out of tolerance, not yet adjusted

3. #3Adjusted, as-left +0.10 → passes

   Adjustment brought it inside the as-left limit

4. #4Adjusted, as-left +0.40 → does not pass

   Inside the as-found band but outside the tighter as-left band

5. #5As-found -0.80 → adjust required

   Drift below zero counts too

6. #6Out, not adjusted, as-left looks good → no pass

   A good as-left reading without an adjustment is not a pass

7. #7Limits include their edge

   As-found 50 and as-left 25 are inside; 51 and 26 are outside