Technical Trade SchoolBAS-100 foundation-series
BAS-107
Concept reading and source route

BAS-107 Reading Guide

How to use this reading guide

This is the concept-review layer for a 100% online course. Read each module before its lesson, complete the retrieval prompts without looking, then use the linked authoritative sources to verify project-specific editions, requirements, and manufacturer procedures.

Online evidence is not OJL: browser simulations, document cases, and isolated remote equipment build reasoning and documentation skill; supervised field performance is recorded separately.

Module 1

Number sense, signs, fractions, decimals, percentages and estimation

Why it matters: The equation and units are part of the answer; extra decimal places do not create accuracy.

Vocabulary and working scope

Place value; positive/negative; fraction/decimal; ratio; percent; percent change; rounding; significant precision; order of operations; calculator entry; mental estimate; bounds.

Source-to-result trace

  1. Locate the controlling requirement and establish authority.
  2. Identify the physical and digital boundaries.
  3. Preserve as-found state and timestamps.
  4. Trace the initiating condition through logic, interfaces, equipment, and process response.
  5. Compare expected and actual evidence.
  6. Calculate with units and stated tolerance.
  7. Record action, result, restoration, uncertainty, and owner.

Worked thinking prompt

A calculator reports 2,400 percent damper position after a decimal is misplaced.

Calculation: Convert fractions/decimals/percent, calculate percent difference/change, round to justified precision, and bound results.

Retrieval prompts

Module 2

Units, dimensions, prefixes and conversion factors

Why it matters: Never combine unlike units silently; squared and cubed conversions apply the factor more than once.

Vocabulary and working scope

Length/area/volume; time; temperature; pressure; flow; mass; energy/power; electrical units; milli/kilo/mega; dimensional analysis; conversion factor; squared/cubed units.

Source-to-result trace

  1. Locate the controlling requirement and establish authority.
  2. Identify the physical and digital boundaries.
  3. Preserve as-found state and timestamps.
  4. Trace the initiating condition through logic, interfaces, equipment, and process response.
  5. Compare expected and actual evidence.
  6. Calculate with units and stated tolerance.
  7. Record action, result, restoration, uncertainty, and owner.

Worked thinking prompt

A duct area in square inches is entered as square feet without squaring the conversion factor.

Calculation: Convert common SI/IP quantities, C/F temperature, pressure and flow from supplied factors, with dimensional cancellation and reasonableness.

Retrieval prompts

Module 3

Measurement, scales, drawings, geometry and quantities

Why it matters: Use written dimensions and verified scale correctly; sketches and screen zoom are not reliable measuring tools.

Vocabulary and working scope

Tape/ruler; scale; dimension; plans; length/perimeter; area; volume; triangles; Pythagorean relationship; angle; conduit offset awareness; route allowance; material count; waste/spare.

Source-to-result trace

  1. Locate the controlling requirement and establish authority.
  2. Identify the physical and digital boundaries.
  3. Preserve as-found state and timestamps.
  4. Trace the initiating condition through logic, interfaces, equipment, and process response.
  5. Compare expected and actual evidence.
  6. Calculate with units and stated tolerance.
  7. Record action, result, restoration, uncertainty, and owner.

Worked thinking prompt

A 1/4-inch scale drawing is printed at 90 percent, changing every measured route.

Calculation: Calculate scaled distance, area/volume, right-triangle/rolling-offset geometry, quantities, allowances, and print-scale error.

Retrieval prompts

Module 4

Algebra, equations, ratios, proportions and interpolation

Why it matters: Keep units attached while rearranging; a valid algebraic step can still violate the model domain or physical limits.

Vocabulary and working scope

Variable; isolate; inverse; ratio; proportion; linear equation; slope/intercept; interpolation; lookup table; graph; domain/range; piecewise awareness.

Source-to-result trace

  1. Locate the controlling requirement and establish authority.
  2. Identify the physical and digital boundaries.
  3. Preserve as-found state and timestamps.
  4. Trace the initiating condition through logic, interfaces, equipment, and process response.
  5. Compare expected and actual evidence.
  6. Calculate with units and stated tolerance.
  7. Record action, result, restoration, uncertainty, and owner.

Worked thinking prompt

A linear reset equation is extrapolated beyond its defined outdoor-temperature range.

Calculation: Solve and rearrange one/two-step equations, ratios, slopes, interpolation, and clamp results to supplied limits.

Retrieval prompts

Module 5

Electrical math: Ohm, power, VA, transformers and voltage drop

Why it matters: A steady-state voltage-drop answer is not full design proof when inrush, temperature, protection, or manufacturer minimums remain unknown.

Vocabulary and working scope

V=IR; P=VI; VA; AC awareness; series/parallel; transformer load; source capacity; one-way versus loop length; conductor resistance; Vdrop; delivered voltage; percent drop; margin.

Source-to-result trace

  1. Locate the controlling requirement and establish authority.
  2. Identify the physical and digital boundaries.
  3. Preserve as-found state and timestamps.
  4. Trace the initiating condition through logic, interfaces, equipment, and process response.
  5. Compare expected and actual evidence.
  6. Calculate with units and stated tolerance.
  7. Record action, result, restoration, uncertainty, and owner.

Worked thinking prompt

Three actuators share a 24 Vac transformer and the farthest resets during simultaneous startup.

Calculation: Calculate current from VA/V, total VA, loop resistance, Vdrop=IR, delivered voltage, percent drop, spare capacity, and reasonableness.

Retrieval prompts

Module 6

Signal scaling, calibration, error and engineering units

Why it matters: Correct arithmetic on the wrong range, unit, signal type, or reference is still wrong.

Vocabulary and working scope

Raw counts awareness; 0-10 V; 4-20 mA; resistance table; lower/upper range; linear equation; offset/span; clamp; percent; binary/enumerated; calibration error; percent span.

Source-to-result trace

  1. Locate the controlling requirement and establish authority.
  2. Identify the physical and digital boundaries.
  3. Preserve as-found state and timestamps.
  4. Trace the initiating condition through logic, interfaces, equipment, and process response.
  5. Compare expected and actual evidence.
  6. Calculate with units and stated tolerance.
  7. Record action, result, restoration, uncertainty, and owner.

Worked thinking prompt

A 4-20 mA 0-250 Pa sensor is interpreted as 0-20 mA and displays a plausible error.

Calculation: Apply EU=LRV+(signal-livezero)/(span) x range, inverse scaling, percent span, offset/slope, and tolerance.

Retrieval prompts

Module 7

HVAC math: airflow, heat, mixing, hydronics and efficiency

Why it matters: Shortcut constants embed assumptions about fluid and conditions; always state them and use project/engineering values when required.

Vocabulary and working scope

Delta T; CFM; air heat 1.08 awareness; water heat 500 awareness; mixed-air weighted average; ventilation fraction; ton/Btu/h/kW; efficiency/COP awareness; assumptions; density/specific heat.

Source-to-result trace

  1. Locate the controlling requirement and establish authority.
  2. Identify the physical and digital boundaries.
  3. Preserve as-found state and timestamps.
  4. Trace the initiating condition through logic, interfaces, equipment, and process response.
  5. Compare expected and actual evidence.
  6. Calculate with units and stated tolerance.
  7. Record action, result, restoration, uncertainty, and owner.

Worked thinking prompt

A glycol loop is calculated with the standard water constant and appears to meet capacity.

Calculation: Calculate air/water heat, mixed air, ventilation fraction, unit conversions, load/capacity comparison, and reasonableness.

Retrieval prompts

Module 8

Pressure, flow, fan/pump and proportional relationships

Why it matters: Proportional, square, and cube relationships have specific domains; device position is rarely equal to process flow.

Vocabulary and working scope

Static/differential pressure; square relationship; airflow K sqrt(DP); fan/pump affinity awareness; speed; flow; pressure/head; power; valve/damper position versus process; limits.

Source-to-result trace

  1. Locate the controlling requirement and establish authority.
  2. Identify the physical and digital boundaries.
  3. Preserve as-found state and timestamps.
  4. Trace the initiating condition through logic, interfaces, equipment, and process response.
  5. Compare expected and actual evidence.
  6. Calculate with units and stated tolerance.
  7. Record action, result, restoration, uncertainty, and owner.

Worked thinking prompt

A fan speed increases 10 percent and the learner predicts only 10 percent more power.

Calculation: Calculate square-root airflow, affinity-law examples, percent change, bounds, and compare predicted/observed response.

Retrieval prompts

Module 9

Network math, binary/hex awareness, time and data rates

Why it matters: Address calculations support planning and diagnosis but do not authorize using unassigned addresses or changing owner networks.

Vocabulary and working scope

Bits/bytes; decimal/binary/hex awareness; IPv4 octets; subnet mask/prefix; network/host/broadcast; device counts; baud; polling/COV rate; latency; sample interval; storage/retention.

Source-to-result trace

  1. Locate the controlling requirement and establish authority.
  2. Identify the physical and digital boundaries.
  3. Preserve as-found state and timestamps.
  4. Trace the initiating condition through logic, interfaces, equipment, and process response.
  5. Compare expected and actual evidence.
  6. Calculate with units and stated tolerance.
  7. Record action, result, restoration, uncertainty, and owner.

Worked thinking prompt

A controller is assigned an address outside the VLAN subnet and trends fill storage faster after polling changes.

Calculation: Calculate subnet membership from supplied prefix, usable-count awareness, transmission/update time, samples/day, storage, and retention.

Retrieval prompts

Module 10

Trends, averages, rates, tolerance, uncertainty and reasonableness; Integrated calculation record, error diagnosis and defense

Why it matters: An average can hide cycling and a correlation can hide sequence, mode, time, or secondary cause. The professional product is not a naked number; it is a reproducible decision record with limits and a reasonableness check.

Vocabulary and working scope

Mean/median/range; min/max; rate of change; percent time; sampling; missing/duplicate/stale data; tolerance; accuracy; resolution; uncertainty awareness; correlation; baseline; outlier. Givens; source; diagram; units; equation; work; result; estimate; bounds; tolerance; changed case; spreadsheet/calculator audit; interpretation; limitation; reviewer handoff.

Source-to-result trace

  1. Locate the controlling requirement and establish authority.
  2. Identify the physical and digital boundaries.
  3. Preserve as-found state and timestamps.
  4. Trace the initiating condition through logic, interfaces, equipment, and process response.
  5. Compare expected and actual evidence.
  6. Calculate with units and stated tolerance.
  7. Record action, result, restoration, uncertainty, and owner.

Worked thinking prompt

Average zone temperature is acceptable, but five-minute oscillations create repeated complaints. Changed case: A spreadsheet gives convincing totals but uses feet as inches, one stale sensor value, and the wrong operating mode.

Calculation: Calculate average/median/range/rate, percent time outside band, missing data, combined tolerance awareness, and compare to physical limits. Recalculate independently, quantify error impact, reconcile all units/assumptions, and score calculation/record completeness.

Retrieval prompts

Required and deeper reading

Adoption note: Standards, codes, project requirements, owner criteria, manufacturer instructions, and employer safety programs control. Confirm the adopted edition and authority before applying a numeric requirement.