Chapter 14 Exercises

These exercises range from safe observation (identifying wiring types, testing outlets) to hands-on work (replacing an outlet or switch). Follow all safety protocols exactly. Where a permit may be required, this is noted clearly.

Exercise 1: Identify the Wiring Type in Your Home

Objective: Identify what type of wiring is present in your home and understand its implications.

Safety note: Observation only in this exercise. Do not touch any wiring.

Instructions:

  1. Basement or attic inspection: Go to your basement or attic (wherever wiring is most visible). Look for runs of cable or conduit along the framing. What do you see?
  • NM cable (Romex): Plastic-jacketed cable, flat or slightly rounded, with a label printed on the jacket showing gauge and conductor count (e.g., "12/2 NM-B" or "14/2 NM-B")
  • BX/Armored cable: Metal spiral sheath, flexible
  • Conduit: Metal (EMT/rigid) or plastic (PVC) pipe with wires running inside
  • Knob-and-tube: Individual wires running separately, supported on ceramic knobs (look like small porcelain mushrooms), passing through ceramic tubes in the framing

  1. Date check: When was your home built? What wiring type(s) would you expect based on the chapter?

  2. If you have knob-and-tube: Note whether it appears to be active (connected to circuits and presumably carrying power) or abandoned (wires cut and capped, not connected to anything). Is any K&T wiring in contact with or buried under attic insulation?

  3. Wire color check (safe, exposed wires only): If you can see any exposed wires in the basement or at the panel without touching them, are they copper-colored (orange-gold) or silver/gray? Silver-gray wires on branch circuits (not service entrance) may indicate aluminum branch circuit wiring.

Questions: 1. What wiring type(s) did you find in your home? 2. If you found knob-and-tube wiring, what are the three main concerns associated with it? 3. If your home was built between 1965 and 1973, what specific wiring concern should you investigate further?

Exercise 2: Audit Your Outlets with an Outlet Tester

Objective: Test every accessible outlet in your home and create a report of what you find.

What you need: A plug-in outlet tester (3-light type), $5–$15 at any hardware store. A notebook or phone for recording results.

Safety note: This exercise involves only plugging a tester into outlets — no live wire contact.

Instructions:

  1. Go room by room through your entire home.
  2. Plug the outlet tester into every accessible outlet.

  3. Record the result for each: - Correct wiring (all correct lights) - Open ground - Open neutral - Open hot - Hot/neutral reversed - Hot/ground reversed

  4. Create a simple map: sketch your home's floor plan (or use a room list) and mark each outlet with its test result.

  5. Count: - Total outlets tested: _ - Outlets showing correct: - Outlets showing open ground: _ - Outlets showing reversed polarity: - Outlets not working: _ - Other issues: _

Questions: 1. What percentage of your outlets showed correct wiring? 2. Open grounds are common in pre-1960s homes. Are yours clustered in older areas of the home (original construction) vs. newer areas (additions, renovations)? 3. Any outlet showing hot/neutral reversed or hot/ground reversed is a safety hazard. Did you find any? What is the appropriate response? 4. If you found a non-functional outlet (open hot), how would you determine whether it's the outlet itself that has failed, or a problem elsewhere on the circuit?

Exercise 3: Identify GFCI and AFCI Protection in Your Home

Objective: Determine where GFCI and AFCI protection exists in your home and where it may be lacking.

Instructions:

  1. GFCI audit: Walk every bathroom, kitchen, garage, outdoor area, and basement/crawl space. Look for outlets with TEST and RESET buttons — these are GFCI outlets. Also check your panel for any GFCI breakers.

For each GFCI outlet: press the TEST button. Does the GFCI trip (power cuts off to that outlet)? Press RESET — does power return? A GFCI that doesn't respond to TEST is faulty.

Are there any outlets in bathrooms, kitchens (within 6 feet of a sink), garages, or outdoor locations that do NOT have GFCI protection — either at the outlet itself or via a GFCI breaker or upstream GFCI outlet?

  1. AFCI audit: Look at your panel (door open, cover on). Are any bedroom or living room circuits protected by AFCI breakers (look for "TEST" buttons on breakers and "ARC FAULT" labeling)?

Questions: 1. Are all required GFCI locations in your home properly protected? 2. If a GFCI outlet in your kitchen controls downstream outlets in the same area (that don't have TEST/RESET buttons themselves), how would you verify which outlets are protected? 3. If you found a location that should have GFCI protection but doesn't, what are your options for adding it? (List at least two.)

Exercise 4: The Wire Gauge Challenge

Objective: Understand and apply the wire gauge/ampacity table from Section 14.2.

Instructions:

Answer these questions using the wire gauge ampacity table:

  1. Dave Kowalski wants to run a circuit for a 240V air compressor that draws 28 amps. What is the minimum wire gauge required? What size breaker?

  2. A bedroom circuit uses 14-gauge wire and has a 20-amp breaker installed. What is wrong with this? What is the correct fix?

  3. You are replacing a 240V dryer outlet. The cable in the wall is 10-gauge, 3-conductor NM cable. What is the maximum breaker size this cable can support?

  4. You find a cable labeled "12/3 NM-B" in your attic. Interpret this label completely: what is the gauge, how many conductors, what type of cable?

  5. For each of the following circuits, identify the correct wire gauge: a) Kitchen countertop outlet circuit (20A, 120V) b) Electric dryer (30A, 240V) c) Large electric range (50A, 240V) d) General bedroom lighting (15A, 120V) e) Level 2 EV charger (48A, 240V)

  6. What is the "80% rule" for continuous loads? Apply it: what is the maximum continuous load (in amps) on a 20-amp circuit?

Exercise 5: Safe Outlet Replacement (Hands-On)

Objective: Practice the complete process of safely replacing a standard outlet with a tamper-resistant outlet.

Skill level: Accessible to careful homeowners with basic mechanical skill. Permit required? In most jurisdictions, replacing an existing outlet in-kind (same location, same function, no circuit change) does not require a permit. If you are upgrading to GFCI (which changes the device type), check with your local building department. When in doubt, ask.

What you need: - Non-contact voltage tester (mandatory) - Flathead and Phillips screwdrivers - Needle-nose pliers - A new tamper-resistant duplex outlet (match the amperage of the existing outlet — 15A or 20A) - Optional: outlet tester to verify correct wiring after installation

Instructions:

  1. Select an outlet to replace — ideally in a bedroom or living room where you can verify your circuit from your panel map.

  2. Turn off the circuit breaker for that circuit.

  3. Verify with non-contact voltage tester that the outlet is de-energized. Hold the tester near each slot of the outlet. Confirm it does not beep or light. If it does — stop. Recheck your panel map and turn off the correct breaker.

  4. Test your voltage tester on a known-live outlet to confirm it's working.

  5. Remove the cover plate and outlet mounting screws. Pull the outlet out of the box.

  6. Test every wire in the box with the NCV tester. If any wire is live, stop and identify why.

  7. Photograph the existing wiring configuration before disconnecting anything.

  8. Identify whether this is an end-of-run outlet (one cable) or middle-of-run (two cables).

  9. Disconnect the wires from the old outlet. Do not use backstab/push-in terminals on the new outlet.

  10. Connect wires to the new outlet using the screw terminals: black to brass, white to silver, bare copper to green ground screw. Form J-hooks and tighten firmly.

  11. Fold wires neatly into the box. Mount the outlet with screws. Install cover plate.

  12. Turn the breaker back on. Test with the outlet tester. Confirm "correct wiring" indication.

Questions: 1. What does it mean if your outlet tester shows "open ground" after replacement? 2. If you found backstab connections on the outlet you removed, is this a concern? Why might backstab connections fail? 3. What should you do if you discover aluminum wiring when you open the outlet box?

Exercise 6: Switch Identification

Objective: Identify the types of switches in your home and understand their wiring.

Instructions:

Walk through your home and find examples of each switch type. For each, note what it controls and how many switch locations control that same fixture.

  1. Single-pole switches: Controls a light or fan from one location only. Toggle shows ON/OFF markings. How many single-pole switches do you have?

  2. Three-way switches: Controls a fixture from two locations. Toggle does NOT show ON/OFF markings. Find examples (stairways, hallways, rooms with multiple entries).

  3. Dimmer switches: Controls lighting level. Rotary, slider, or touch-style. Note the brand if visible — look it up to determine whether it's LED-compatible.

  4. Any four-way switches: Controls a fixture from three or more locations. Uncommon in most homes; found in large rooms or hallways.

  5. Occupancy/vacancy sensors: Motion-sensing switches. Note locations.

Questions: 1. For the three-way switches you found: draw a simple diagram of the two switch locations and the fixture they control. Where does power enter the circuit — at the fixture, at one switch, or at the other switch? 2. If one of your three-way switches seems to work "backwards" (moving the toggle up turns the light off instead of on), does this indicate a wiring error? Explain. 3. You have a dimmer switch currently controlling an incandescent bulb. You want to swap the bulb for an LED. What must you verify about the dimmer before making this change?

Exercise 7: Junction Box Hunt

Objective: Locate the junction boxes in your home and verify they are accessible and properly covered.

Instructions:

Inspect every accessible area of your home — basement ceiling, attic (if accessible and safe to enter), utility room, garage — for electrical junction boxes.

For each junction box you find: 1. Is it covered with a flat cover plate? (Required) 2. Is the cover plate accessible without demolishing the building structure? (Required) 3. Is the box recessed into a wall or ceiling (with a cover plate flush with the surface) or surface-mounted? 4. Is there any evidence of damage, overheating, or water intrusion at the box?

If you find any uncovered junction boxes, boxes with only a wire nut cap protruding (no box cover), or wires connected in open space without a box at all — these are safety and code violations that should be corrected.

Questions: 1. Did you find any junction boxes without proper covers? What is the required correction? 2. Why does code require that junction boxes remain accessible after the work is done? 3. You discover a wire splice in your attic between two NM cables, connected with a wire nut but not inside a box. What must you do to bring this to code compliance?

Exercise 8: Research — Permits and DIY in Your Jurisdiction

Objective: Understand the specific electrical permit requirements for homeowners in your jurisdiction.

Instructions:

Contact your local building department (a phone call or their website) and ask:

  1. Does your jurisdiction allow homeowners to pull electrical permits for work in their own primary residence?
  2. If yes: what types of electrical work require a permit? (Is replacing a single outlet permit-required? Adding a new circuit? Service work?)
  3. What is the permit fee for a typical homeowner electrical permit (small job — one or two new circuits)?
  4. What is the inspection process? Does an inspector need to come out, or is it a "self-inspection" with photos submitted?
  5. What work, if any, requires a licensed electrician regardless of permit status?

Questions: 1. Were you surprised by what your jurisdiction allows homeowners to do (either more or less than you expected)? 2. If permits are available to homeowners, what is the practical benefit of pulling one even for work you could legally do without it? 3. Dave Kowalski is in a rural county and wants to add shop circuits. Based on your jurisdiction's typical requirements (or your research into rural county norms), what permit requirements should he expect?