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[Class 2 Electrician Skill Test] 10 Published Questions Strategy [Pilot Lamp Simultaneous Flashing Circuit]

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Master the pilot lamp simultaneous flashing circuit and electrical outlet all at once.

Actually, I am also learning by summarizing things like this lol

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So, here you go.

Basic information

  • Exam question: Published question 10 (assumed based on 2025 candidate question No. 10)
  • The theme of this exam number:
    Problem with wiring the pilot lamp "simultaneous flashing" circuit and the outlet/light circuit together.
    (The key point is the combination of circuit breaker + pilot lamp + outlet + electric light) (HOZAN, 2025)

This question 10 is a typical question in the Type 2 Electrician Skills Test that checks whether you understand the pilot lamp wiring properly.
In particular, if you don't understand the difference between "simultaneous flashing" and "constantly lit/differently flashing", you can easily get lost when looking at double-track diagrams.

Tools needed for this exam

In addition to the basic set, I will also write down points that are particularly useful for "Problems with Pilot Lamps."

  • Driver (plus/minus)
  • electrician knife
  • VVF stripper
    Example: HOZAN's VVF stripper (P-958, etc.) is suitable for skill tests because it stably strips 1.6mm and 2.0mm coatings. (HOZAN, 2025)
    → On the blog side, this is an easy point to insert a link to Amazon or Yahoo Shopping.
  • Passing multi-tool (HOZAN electrician exam multi-tool)
    • Tightening the lock nut
    • Fixing the switch frame tab by bending it
    • Make it easier to push the ring sleeve
      It is useful in multiple situations such as (from Gamidenki channel commentary) (Gamidenki channel)
  • Crimping tools (for ring sleeves: P-738, etc.) (Hozan)
  • pliers/nippers
  • major (scale)
  • Voltage detector (use to check polarity during practice to deepen your understanding)

Materials to be prepared for this exam

Based on HOZAN's Candidate Problem No. 10, the material composition will be roughly as follows (please be sure to prioritize the "construction conditions" in the problem text for the detailed length of the day). (HOZAN, 2025)

  • electric wire
    • VVF 1.6mm x 2 cores approximately 650mm
    • VVF 1.6mm x 3 cores approximately 450mm
    • VVF 2.0mm x 2 cores approximately 300mm
      → 2.0mm² has an allowable current of about 27A (ambient temperature 30℃, single-core cable equivalent), and is often used on the main line side of branch circuits and around molded circuit breakers (based on general values ​​such as JIS C 3342).
  • Equipment (estimated)
    • Hardwire circuit breaker (safety breaker) 1 piece
    • 1 lamp receptacle
    • Hanging ceiling (square) 1 piece
    • Embedded continuous mounting frame 1 piece
    • Single pole switch (recessed type) 1 piece
    • Outlet (embedded type) 1 piece
    • Pilot lamp (embedded type) 1 piece
    • Ring sleeve small 1 piece
    • Ring sleeve medium 1 piece
    • Plug-in connector (for 3 connectors) 1 piece

As you can see, the configuration does not have many fixtures, but understanding the pilot lamp wiring is essential.

On the actual question paper, the ``distance between cores'' of each cable is indicated in dimensions such as 100 mm, 150 mm, and 200 mm. On the other hand, the idea is to cut the cable by adding the length that will fit inside the device or the length required for the joint (Electrical Shop Peko, 2023).

Main flow

Here, we will organize the standard way to proceed with Question 10, keeping in mind time allocation.

  1. Reading construction conditions (2-3 minutes)
  2. Check the single line diagram and understand the meaning of "simultaneous blinking" (3 to 5 minutes)
  3. Creating a double line diagram (7-10 minutes)
  4. Cutting out the wire and stripping the sheath (10 to 12 minutes)
  5. Wiring on the device side (10-15 minutes)
  6. Wiring and crimping inside the joint box (10 to 15 minutes)
  7. Final confirmation/Continuity image check (5 minutes)

The total time is about 40 to 50 minutes, but the actual exam is 40 minutes. The above is a guideline for practice, so in actual practice, it is best to shorten the "double line diagram - cutting out" time in training so that you have at least 10 minutes to spare.

How to use HOZAN's passing multi-tool

There are three typical situations where you can use the "passing multi-tool" for Question 10:

  1. Support for pushing wire into ring sleeve
    • If 2.0mm² and 1.6mm² wires are mixed on the main line side, it will be difficult to push the wire into the ring sleeve.
    • If you place the protruding part of the multi-tool on the head of the ring sleeve and push it all the way to the base, it will be easier to keep the core wire exposed to less than 1cm (HOZAN video also shows how to use it in the same way) (Hozan).
    • If the wire protrudes by more than 1cm, it will become a defect, so as a quantitative guideline, aim for 0 to 5mm of core wire exposure.
  2. Fixing the mounting frame and switch/pilot lamp
    • Gamidenki Channel introduces a method of folding the ``frame tabs'' inward using a passed multi-tool when fixing the mounting frame and switch (Gamidenki channel).
    • By firmly tightening the top and bottom of the frame, you can prevent the equipment from wobbling or falling off. This is extremely important in order to prevent "insufficient fixation of equipment", which is a defective item in the test.
  3. Tightening the lock nut
    • Problem 10 often involves no metal pipe construction, but if a lock nut is used in a molded circuit breaker, etc., you can secure it more securely than by hand alone by inserting the groove of a qualified multi-tool into the lock nut and tightening it (from Gamidenki channel).

In your blog, if you include the product link for "HOZAN Qualified Multi-Tool" in a natural way around here, it will be easier for readers to purchase it.

How to draw wiring diagrams and things to be careful about

1. First, clarify the meaning of "simultaneous flashing"

There are typically three types of pilot lamp wiring methods (HOZAN, 2025).

  1. Always on
    • Regardless of the main circuit switch, it lights up all the time while the power is turned on.
  2. Flashing simultaneously
    • Lights up at the same time only when the main circuit load (lights, etc.) is on.
  3. Blinking at different times
    • The pilot lights up when the main circuit is off (reverse operation).

In question 10, the theme is "simultaneous blinking".
The wiring diagram for simultaneous flashing is as follows.

  • "One terminal" of the pilot lamp: Connect to the ground side (white wire) of the power supply
  • Other terminal: Connect to the "switch return wire (black or color designated wire)" from the switch to the load

In other words, it is simple if you remember that ``connect it so that it straddles the same two points as the load'' (HOZAN, 2025).
A voltage of 100V appears between these two points only when the switch is ON, so the electric light and pilot lamp light up at the same time (100V = potential difference between the non-grounded side and the grounded side of the power supply).

2. Steps to convert single line diagram to double line diagram

When drawing a double-line diagram, we recommend the following order:

  1. Draw the power supply (L: black / N: white) assuming it is at the bottom left of the diagram.
  2. Connect the ground side (white) directly to the W side of the outlet and each load (lamp receptacle, hook ceiling, pilot lamp).
    • The image is that the ground side branches out and goes to each load.
  3. Connect the non-grounded side (black) to "Made-in circuit breaker → switch → load"
  4. “Simultaneous flashing” of pilot lamps
    • One side is grounded
    • Connect one side to the "switch return wire" between the switch and the load
  5. The outlet is
    • W side: Ground side (white)
    • H side: Non-grounded side (black)
      (Be careful of the polarity, as it is easy to detect defects.)

3. Memo of wire color and thickness

In HOZAN's explanation, it is recommended to note down the ``wires of different thickness'' and ``color specifications'' at the double-line diagram stage (Hozan).

  • 2.0mm² VVF is used around main lines and breakers (note "2.0" in the diagram)
  • 1.6mm² VVF is used for general lighting/outlet side
  • Be sure to write the designated colors (e.g., white = ground side, black = non-ground side, remaining colors = switch return wire, etc.) in the diagram.

At this stage, make a note of ``which connection point will be the small/medium ring sleeve'' so you don't get confused later when crimping. The marks on the crimping tool (small = "○", medium = "△", etc.) should correspond to the P-738 stamp (Hozan).

How to proceed with practical skills and take a breather

Here, we will break down the actual work procedure into as detailed a material level as possible.

Step 1: Load construction conditions (2-3 minutes)

  • Circle the "distance between devices," "type and thickness of cable to be used," and "pilot lamp lighting conditions (simultaneous flashing)" with markers.
  • In particular, where there are specifications such as "wire length 300 mm," copy them in your notes to avoid cutting mistakes (Hozan points out that even in the HOZAN text, length specifications are often overlooked).

Step 2: Creating a double line diagram (7-10 minutes)

  1. Pull the grounded side and non-grounded side from the power supply
  2. Connect the ground side (white) to the outlet W side and each load.
  3. Non-grounded side (black) to breaker → switch → each load
  4. pilot lamp,
    • One side: Ground side (white)
    • One side: return wire from switch to load
      connect to and draw
  5. Draw “small” and “medium” marks on the crimp connection points.
  6. Also write the thickness and type of wire (VVF1.6-2C, etc.)

At this point, it would be ideal to just assemble the parts according to the double-track diagram.

Step 3: Cutting out the cable and stripping the sheath (10-12 minutes)

  1. Measure the specified length with a tape measure and cut the VVF
    • Example: If 300mm is specified, it is safe to cut to within ±10mm.
    • The video by Denkiya Peko also explains that it is important not to deviate too much from the specified length.
  2. At the connection part inside the joint box, remove about 100mm of the sheath and expose about 25mm of the core wire (Gamidenki's ``C = 10cm, core wire 2.5cm'' rule can be used as is for many problems) (Gamidenki channel).
  3. If you use a VVF stripper,
    • 2.0mm² → Strip the sheath with a compatible scale
    • 1.6mm² → Strip the coating with a 1.6 blade
      Just by changing the position of the blade, you can peel it off at a stable length.

Step 4: Wiring the instrument side (10-15 minutes)

  1. outlet
    • W side terminal: White wire (ground side)
    • H side terminal: Black wire (non-grounded side)
      Connect securely. Most recent types have screw terminals with a core wire of about 10 mm exposed, and are inserted straight into the terminal without being twisted.
  2. Lamp receptacle/hook ceiling
    • White wire on the ground side terminal
    • Return wire from switch to non-ground terminal (black or other color)
      Connect.
  3. pilot lamp
    • One side terminal: Ground side (white wire)
    • Other side terminal: return wire from switch to load
      Connect. If you make a mistake here, it will turn on "always on" or "reverse operation", so please compare it with the double-track diagram many times.

At this stage, it is more efficient to just temporarily attach the parts to the mounting frame, and then fix the frame all at once.

Step 5: Wiring and crimping inside the joint box (10-15 minutes)

  1. Organize each wire according to the double line diagram
    • The ground side (white) branches to "power supply → outlet → each load → pilot lamp ground side"
    • The non-grounded side (black) is "power supply → breaker → switch input" etc.
    • Return lines are organized as "switch output → each load → pilot lamp"
  2. When inserting into the ring sleeve,
    • Adjust so that the core wire does not protrude more than 1cm from the bottom edge of the sleeve, preferably within 0 to 5mm (HOZAN's video clearly states that ``If it is visible more than 1cm, it is unacceptable'') (Hozan).
    • If it is difficult to insert, use a multi-tool to push in the sleeve head to make it easier.
  3. Crimping without making mistakes with the marks on the crimping tool
    • 2.0＋1.6＋1.6のように太さと本数が混在する場合は「中」マーク、それ以下なら「小」マーク、という具合に事前メモどおりに圧着マークを選びます(Hozan)。

For peace of mind, every time you finish crimping one place, check to see if it comes loose by pulling gently on just the crimped wire.

Step 6: Fixing and finishing the equipment (5-7 minutes)

  1. Set the switch, outlet, and pilot light on the mounting frame
    • Gamidenki channel recommends fitting the device into the mounting frame and then using a certified multi-tool to tilt the tabs inward to secure it in place (Gamidenki channel).
    • By firmly tightening the top and bottom two places, it prevents rattling and falling off.
  2. Orientation of the instrument
    • Make sure the “W” mark on the outlet is facing up.
    • The pilot lamp/switch ON/OFF display is now in the correct direction.
      Check.
  3. Arrange the wires inside the joint box and check for excessive bends or crushing.

Items to check for defects and oversights

We will summarize the flaw points that are particularly easy to make in Question 10 in a checklist format.

  1. パイロットランプの接続ミス
    • Not connected to ground side
    • スイッチ戻り線ではなく、電源側黒に直結してしまい「常時点灯」になっている
      → Be sure to check whether the load crosses the same two points on the double-track diagram.
  2. Wrong polarity of outlet
    • Add black to the W side
      → Since the risk of electric shock increases in practice, it will be treated as a serious defect in the test.
  3. 圧着マークの誤り
    • "Small" and "medium" are reversed in terms of number and thickness.
      → Check the markings on the crimping tool and the notes on the double-track diagram before crimping.
  4. Exposed core wire/caught in the coating
    • The core wire protrudes more than 1 cm from the bottom edge of the ring sleeve.
    • On the other hand, the sheathing penetrates too far into the sleeve and the core wire is not sufficiently gripped.
      → Pass It will stabilize if you imagine "exposure 0-5mm" while pushing in with a multi-tool (Hozan).
  5. Improper fixation of switch/pilot lamp
    • The nails on the mounting frame are not folded properly and the device is shaking.
      → Place the tip of the pass multi-tool into the groove and securely fix it by ``folding the tabs inward'' (Gamidenki channel).
  6. Mistake in wire thickness and type
    • The area around the breaker that should have been 2.0mm² was constructed with 1.6mm².
      → The construction conditions clearly state "VVF2.0-2C", etc., so write the thickness on the double-track diagram and cut accordingly.

Summary

Problem 10 is that although the number of instruments itself is not large,

  • Simultaneous flashing of pilot lamps
  • outlet polarity
  • VVF with different thickness (1.6mm and 2.0mm)
  • Correct selection and crimping of ring sleeves

These questions are packed with ``the basics you need to know in the skill exam'' such as:

If you practice a few times and get to the point where you can naturally visualize the connection pattern by looking at a multi-track diagram, you will be able to mentally prepare for the actual performance.

Reference materials/cited sources

  • HOZAN Co., Ltd. “Class 2 Electrician Examination Tiger Candidate Question No. 10 2025 Edition” View date: November 16, 2025 (Made-in circuit breaker + simultaneous flashing pilot lamp circuit, material list, wiring points)
  • HOZAN Type 2 Proficiency Test Explanation Video Text (Crimping mark on ring sleeve, explanation on handling of 2.0mm eco electric wire) (Hozan)
  • Gamidenki Channel “Second Class Electrician Skills Test Cable Construction and Passing How to Use the Multi-Tool” (Explanation of how to tighten lock nuts and fix mounting frames and switches) (Gamidenki channel)
  • Electrician Peko “Class 2 Electrician Skill Test Basics of Cable Length and Sheath Stripping (C=10cm, Core Wire 2.5cm Rule)” (Gamidenki channel)

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