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Motor Position Restriction Checker

Run the Motor Position Restriction Checker MicroSim Fullscreen

About This MicroSim

A centrifugal fan's motor can sit in one of the AMCA floor positions W, X, Y or Z, but not every position works with every discharge. On SWSI Arrangements 1, 3 and 3F, FanPedia forbids the position where the motor would block the outlet opening (BHD and TAD discharges) and calls for a height check where the motor may not fit below a Top Horizontal outlet (THD). Arrangement 9SS swingout fans have only two buildable pairings: CW with (L) and CCW with (R).

This MicroSim shows ten order lines in a fixed order. For each line you choose one verdict, Allowed, Not allowed or Height check needed, and submit it. Each line has one scored attempt. After you submit, the sim:

  • marks your verdict ("✓ Correct: Not allowed." or "✗ Not quite: Not allowed.") and shows the reason for the line;
  • opens the reference rule card and highlights the row (and the rotation) that decides the line;
  • marks the drive-side sketch: a dashed box with ✗ for a position that is not allowed, a dashed box with ↕ for a height check.

The running score reads "Verdicts correct: n of 10". After line 10, Show summary lists each line with your verdict and the correct verdict side by side, and states the first-attempt score and whether mastery (9 of 10 on the first attempt) was reached. Opening the rule card is exploration and never changes the score.

The rule the sim applies (FanPedia PDF pp. 53, 162–163, 166):

Discharge CW CCW Reason
BHD Z not allowed W not allowed Motor interferes with the outlet opening
TAD W not allowed Z not allowed Motor interferes with the outlet opening
THD W, height check Z, height check Motor may not fit below the discharge; on Arrangement 1 the pedestal can be lengthened
Arrangement 9SS (L) only (R) only Fixed swingout pairings

Every other combination is allowed. The verdicts come from the kit's FP.codes.checkMotorPosition, the same table the chapter prints. The order lines are illustrative.

How to Use

  1. Read the order line: arrangement, rotation, discharge and motor position.
  2. Pick a verdict (click it or press 1, 2 or 3), then press Submit verdict.
  3. Read the feedback, compare the highlighted rule-card row and the sketch, and press Next line.
  4. After line 10, press Show summary to see your verdicts beside the correct ones. Press Start over at any time to clear the score and return to line 1.

Keyboard: 1 Allowed, 2 Not allowed, 3 Height check needed. Enter submits the chosen verdict, then goes to the next line (Enter on a focused verdict button picks it and submits). R opens or closes the rule card. Tab moves between the buttons.

Data label: "Order lines are illustrative · Source: FanPedia PDF pp. 53, 162–163, 166", shown at the bottom of the drawing column.

Iframe Embed Code

You can add this MicroSim to any web page by adding this to your HTML:

<iframe src="https://moroshek.github.io/FanTASTIC-textbook/sims/ch13-motor-position-restriction-checker/main.html"
        height="718px"
        width="100%"
        scrolling="no"></iframe>

Lesson Plan

Learning Objective

The learner will judge whether each proposed combination of arrangement, rotation, discharge and motor position can be ordered as written, using the FanPedia restriction rules (Bloom: Evaluate, verb: judge).

Audience

Adult professional development: new application engineers, sales staff, representatives and order-entry staff.

Duration

10–15 minutes

Prerequisites

  • Fan arrangements (1, 3, 3F, 9SS)
  • CW and CCW rotation, seen from the drive side
  • Discharge letter codes (BHD, TAD, THD, UBD)
  • Motor positions W, X, Y and Z, and (L) and (R)
  • Motor position restrictions, from Chapter 13

Activities

  1. Judge (7 min): Work through the ten order lines. Before each verdict, say the rotation and the discharge together and name the restricted position for that pair.
  2. Review (3 min): Compare the summary table with your verdicts. For each miss, find the rule-card row that decided it.
  3. Discuss (5 min): Look at lines 1 and 3. Why does BHD forbid Z for CW but W for CCW? Write the corrected line for each line that was not allowed (the chapter's worked example moves line 1 to position W).

Common Misconceptions Addressed

  • A restriction on a position holds for both rotations: lines 1–3 and 4–6 pair the same discharge with both rotations, and the sketch shows the outlet mirror left to right.
  • The THD restriction forbids the position outright: lines 7 and 8 need "Height check needed", not "Not allowed".
  • Arrangement 9SS lets the buyer choose either side for the motor: line 10 shows the two fixed pairings.

Assessment

  • First-attempt score shown as "Verdicts correct: n of 10"; mastery is 9 of 10 on the first attempt.
  • Follow-up: a CCW BHD fan arrives with the motor in W. What would you change, and why?

References

  1. Twin City Fan & Blower. FanPedia: The Fan & Blower Encyclopedia, pp. 52–53 (motor positions, swingout arrangements) and pp. 162–166 (Arrangements 1, 3, 3F and 9SS technical descriptions and motor position restrictions). PDF
  2. Twin City Fan & Blower. FanPedia online - the online edition of the same reference.
  3. AMCA International. ANSI/AMCA Standard 99, Standards Handbook - drive arrangements and motor positions for centrifugal fans. AMCA