ACR 106 Test 3

Comprehensive review flashcards for ACR 106 Test 3 covering HVAC electrical terminology, motor schematics, switch types, capacitor circuits, and meter troubleshooting readings.

CSIR

Capacitive Start Induction Run

PSC

Permanent Split Capacitor

CSCR

Capacitor Start Capacitor Run

MFD

Microfarads

VAC

Volts Alternating Current

DPST

Double Pole Single Throw

SPDT

Single Pole Double Throw

N.O.

Normally Open

N.C.

Normally Closed

DMM

Digital multimeter

VOM

Voltmeter

F

Fan Motor

HERM

Hermetic Compressor

C:

Common

S:

Start

R:

Run

Split Phase Motors

Motors equipped with 2 coils that create a phase shift

Start Winding vs. Run Winding Resistance

The start winding has a higher resistance than the run winding ($\text{Start} > \text{Run}$).

Winding Usage (Start vs. Run)

The run winding is used more than the start winding.

Four Ways to Start a Phase Shift

Start winding, capacitor, 3 phase, and shaded pole

Shaded Pole Motor

A single-phase motor schematically represented by a single run winding coil.

Split Phase Motor

A motor schematic featuring two windings (start and run coils) with a switch in series with the start winding.

Permanent Split Capacitor (PSC)

A motor schematic featuring run and start coils with a run capacitor permanently connected in series with the start winding.

Capacitor Start Induction Run (CSIR)

A motor schematic featuring two coils with a start capacitor and a switch wired in series.

Capacitor Start Capacitor Run (CSCR)

A motor schematic featuring two coils with a run capacitor wired in parallel with a start capacitor and switch combination.

$3\text{\O}$ Delta Motor

A three-phase motor schematic with three windings connected end-to-end forming a delta configuration.

$3\text{\O}$ Wye Motor

A three-phase motor schematic with three windings connected at a common center point in a wye ($Y$) configuration.

Single Pole Single Throw (SPST)

A switch schematic symbol that connects or disconnects a single electrical path.

Single Pole Double Throw (SPDT)

A switch schematic symbol with one common pole that can connect to either of two terminal throws.

Double Pole Double Throw (DPDT)

A switch schematic symbol with two mechanically linked poles that throw simultaneously between two separate sets of contacts.

Resistor

An electrical component schematic symbol represented by a zig-zag line.

Contacts

A schematic symbol consisting of two parallel vertical lines representing electrical switch contacts.

Transformer

A schematic symbol showing two inductive windings coupled across core lines.

Normally Open (NO)

Switch or relay contacts that remain open and do not conduct current until actuated.

Normally Closed (NC)

Switch or relay contacts that remain closed and conduct current until actuated, represented schematically by contact plates with a diagonal slash.

Ground

An electrical reference connection to earth or chassis, represented schematically by progressively shorter parallel horizontal lines.

Capacitor Styles

Single capacitor = start & run; dual capacitor = two runs in one shell; multi capacitor = start & run.

$2$ Capacitors in Series

A wiring arrangement where two capacitors are connected in a single continuous line.

Capacitor Types

1) Start and 2) Run

$2$ Capacitors in Parallel

A wiring arrangement where two capacitors are connected across the same two common junction points.

Total Capacitance in Parallel

Capacitance values add up directly.

Ohms in a Series Circuit

Ohms add up directly.

Ohms in Parallel

Total resistance (ohms) goes down

Amps in Series

Amps stay the same through every component in the circuit.

Amps in Parallel

Amps add up

Volts in Series

Volts add up across each component to equal total source voltage.

Volts in Parallel

Voltage stays the same

Watts in Series and Parallel

Watts add up in both series and parallel circuits.

Capacitor

An electrical schematic symbol represented by one straight plate and one curved plate separated by a gap.

Good Fuse Meter Reading

reads $0\,\Omega$ on an ohmmeter and $0\,\text{V}$ on a voltmeter.

Bad Fuse Meter Reading

reads $\text{OL}$ on an ohmmeter and supplied voltage on a voltmeter.

Closed Switch Meter Reading

reads $0\,\Omega$ on an ohmmeter and $0\,\text{V}$ on a voltmeter.

Open Switch Meter Reading

reads $\text{OL}$ on an ohmmeter and supplied voltage on a voltmeter.

Good Load Meter Reading

reads some appropriate resistance on an ohmmeter and supplied voltage on a voltmeter.

Open Load Meter Reading

reads $\text{OL}$ on an ohmmeter and supplied voltage on a voltmeter.

Shorted Load Meter Reading

reads $0\,\Omega$ on an ohmmeter and $0\,\text{V}$ on a voltmeter.

Ohm's Law

$1\,\text{volt}$ will push $1\,\text{amp}$ through $1\,\Omega$ of resistance.