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newSchoolWorks.com › VoTechWorks › Manufacturing & Marine › Industrial Maintenance › Capstone Project: Integrated Industrial Maintenance System Build › Lesson 1
MFG-INDU16-08 · Lesson 1 · 48 clock hours · theory

System Planning, Safety Documentation, and Design Review

Objective. Given the capstone system specifications, the student will produce a complete job hazard analysis, a written LOTO procedure, an as-built sketch with labeled subsystems, and a PLC I/O list that are verified accurate by the instructor before any build work begins.

⚠ Pending professional review

This lesson, its worked examples and its practice questions has not yet been verified by a licensed engineer or certified journey-level tradesperson or by a certification or approval body. It is a study draft and may contain errors. Do not use it as instructions for work on a job site or on live equipment. Always follow your instructor, your supervising professional, and current official references and regulations.

VoTechWorks program approval and accreditation are still in progress. Credentials are issued only by the certifying bodies named in each program, after their own exams.

Why Planning and Documentation Come First

In industrial maintenance, the most dangerous moment is the one just before you touch the equipment. Rushing into a build or repair without a written plan causes injuries, rework, and equipment damage. For your capstone project you will assemble a multi-subsystem industrial unit — a motor-driven pump with a belt or chain drive, bearing housings, and a PLC-controlled start/stop and fault-indication circuit. Before a single bolt is turned or wire connected, three documents must be complete and instructor-verified: a Job Hazard Analysis (JHA) with a written LOTO procedure, an as-built sketch, and a PLC I/O list. This lesson teaches you how to produce all three correctly.

Job Hazard Analysis (JHA)

A JHA breaks every task in a job into steps, identifies the hazard in each step, and lists the control measure that eliminates or reduces that hazard. For your capstone unit, begin by listing every energy source present:

For each energy source, record the hazard (electric shock, entanglement, fluid injection, crush) and the control (de-energize, guard, block, bleed). Your JHA becomes the front sheet of your LOTO procedure.

Lockout/Tagout — OSHA 29 CFR 1910.147

OSHA's Control of Hazardous Energy standard (29 CFR 1910.147) requires a written, equipment-specific energy-control procedure whenever an employee performs servicing or maintenance on equipment where unexpected energization or release of stored energy could cause injury. Key requirements you must reflect in your written procedure:

1. Identify the machine — name, location, and equipment ID.

2. List every energy source and its magnitude — type, voltage, pressure, weight.

3. Location of every energy-isolating device — disconnect switch, valve, block.

4. Steps to shut down, isolate, and apply lockout/tagout devices — in exact sequence.

5. Method to release or restrain stored energy — bleed pneumatics, block gravity, discharge capacitors.

6. Verification step — attempt to start (try-out) and use a meter or gauge to confirm zero energy before work begins.

Your procedure is written on the facility's equipment-specific LOTO form. A peer reviews it line by line against a 1910.147 checklist before the instructor signs off. No critical safety error is acceptable — any omission of an energy source or verification step fails the review.

PPE for this project includes safety glasses, safety-toed footwear, and electrical-rated gloves when working near energized parts during the try-out phase. Never rely on tagout alone when lockout is achievable.

As-Built Sketch

An as-built sketch is a dimensioned freehand drawing made from the actual hardware — not from a catalog. It shows where every major component sits, how it connects to adjacent components, and where a technician needs access. For your build station, your sketch must include:

Dimension your sketch using a steel rule for longer distances and calipers for shaft diameters, bore sizes, and close tolerances. Write dimensions directly on the sketch with leader lines. During the instructor walk-through, you must be able to point to each labeled item on the actual hardware.

PLC I/O List

A PLC I/O list is the master reference that maps every physical device connected to the PLC to its memory address, its type (input or output), its signal type (discrete, analog), and a plain-language description. For your capstone circuit the list will include:

| Address | Type | Signal | Device Description |

|---------|------|--------|-------------------|

| I:0/0 | Input | Discrete | Start pushbutton, NO contact |

| I:0/1 | Input | Discrete | Stop pushbutton, NC contact |

| I:0/2 | Input | Discrete | Overload relay auxiliary contact |

| O:0/0 | Output | Discrete | Motor starter coil (M1) |

| O:0/1 | Output | Discrete | Run indicator light, green |

| O:0/2 | Output | Discrete | Fault indicator light, red |

After completing the spreadsheet, cross-reference every row against the ladder logic printout. Every rung that uses an address must appear in your list; every physical device on the panel must have an address. Any mismatch is an error that must be corrected before the build begins.

How the Three Documents Work Together

The JHA/LOTO procedure tells everyone how to safely de-energize the system. The as-built sketch tells everyone where the components are. The I/O list tells everyone what signals the PLC is reading and controlling. Together they form the planning package that a professional maintenance technician would prepare before starting any significant job. Completing them before build work is not a formality — it is the habit that keeps workers alive and equipment running.

Key terms9

Job Hazard Analysis (JHA)A written document that breaks a task into steps, identifies the hazard at each step, and specifies the control measure used to eliminate or reduce that hazard before work begins.
Lockout/Tagout (LOTO)A safety procedure — and the OSHA standard 29 CFR 1910.147 that governs it — requiring written, equipment-specific steps to isolate and de-energize equipment and verify zero energy before servicing.
Energy-Isolating DeviceA mechanical device that physically prevents the transmission or release of energy, such as a disconnect switch, circuit breaker, or manually operated valve.
Zero-Energy Verification (Try-Out)The final step of a LOTO procedure in which the authorized employee attempts to start the equipment and uses instruments to confirm that all energy sources are at zero before work proceeds.
As-Built SketchA dimensioned freehand drawing made from actual installed hardware that shows component locations, connection points, clearances, and routing — used as a reference throughout a build or repair.
PLC I/O ListA spreadsheet or table that maps every physical input and output device connected to a programmable logic controller to its memory address, signal type, and plain-language description.
Stored EnergyEnergy that remains in equipment after the main power source is isolated, including charged capacitors, compressed springs, pressurized fluids, and elevated or suspended components.
Discrete SignalA PLC signal that has only two states — ON or OFF (1 or 0) — as opposed to an analog signal that varies continuously over a range.
Equipment-Specific LOTO ProcedureA written lockout/tagout procedure that is unique to one identified machine, listing that machine's exact energy sources, isolating device locations, and de-energization steps as required by OSHA 29 CFR 1910.147.

Worked examples3

1. Your as-built sketch shows the center-to-center distance between the motor shaft and the pump shaft as 14 inches. You measure the actual distance with a steel rule and get 14 and 3/16 inches. What is the dimensional error in inches, and does it meet the 80% accuracy requirement if the tolerance band for 'accurate' is defined as within 1/4 inch (0.25 in)?
  1. Step 1 — Convert the measured value to a decimal: 3/16 in = 0.1875 in, so the measured distance is 14.1875 in.
  2. Step 2 — Calculate the absolute error: |14.1875 − 14.000| = 0.1875 in.
  3. Step 3 — Compare the error to the tolerance band: 0.1875 in < 0.25 in, so this dimension is within tolerance and counts as accurate.
  4. Step 4 — Confirm the 80% rule: if this is one of many checked dimensions, this dimension passes; as long as at least 80% of all checked dimensions are within their tolerance, the sketch meets the requirement.
Answer: The error is 0.1875 in (3/16 in). Because 0.1875 in is less than the 0.25 in tolerance, this dimension is accurate and contributes to meeting the 80% threshold.
2. You use calipers to measure a shaft diameter on your pump and read 1.250 inches on the first jaw closure and 1.248 inches on a second closure. What value should you record on your as-built sketch, and what is the range of your two readings?
  1. Step 1 — List the two readings: 1.250 in and 1.248 in.
  2. Step 2 — Calculate the range (maximum minus minimum): 1.250 − 1.248 = 0.002 in.
  3. Step 3 — Average the two readings for the recorded value: (1.250 + 1.248) ÷ 2 = 2.498 ÷ 2 = 1.249 in.
  4. Step 4 — Record 1.249 in on the sketch and note that the caliper range was 0.002 in, which is within normal hand-measurement repeatability for a steel rule caliper.
Answer: Record 1.249 in as the shaft diameter. The two-reading range is 0.002 in.
3. Your PLC ladder logic printout references addresses I:0/0, I:0/1, I:0/2, and O:0/0, O:0/1, O:0/2. Your I/O list currently has five rows covering I:0/0, I:0/1, O:0/0, O:0/1, and O:0/2. How many addresses are missing, which ones are they, and what category do they belong to?
  1. Step 1 — List addresses in the ladder logic printout: I:0/0, I:0/1, I:0/2, O:0/0, O:0/1, O:0/2 — six total.
  2. Step 2 — List addresses in the I/O list: I:0/0, I:0/1, O:0/0, O:0/1, O:0/2 — five total.
  3. Step 3 — Find the difference by comparing the two lists: I:0/2 appears in the ladder logic but not in the I/O list.
  4. Step 4 — Identify the category: I:0/2 begins with 'I', so it is an input address. One input device (such as the overload relay auxiliary contact) is missing from the I/O list and must be added before sign-off.
Answer: One address is missing: I:0/2. It is an input. Add a row for I:0/2 with its device description (for example, Overload relay auxiliary contact) before submitting the I/O list.

The math in this lesson1

Learners compare measured shaft center distance and repeated caliper readings against as-built values.
N-Q.3
Brush up in the math halls at newSchoolWorks.com:
In class: Students receive a project brief describing a multi-subsystem industrial unit (motor-driven pump with belt/chain drive, bearing housings, and a PLC-controlled start/stop and fault-indication circuit); they individually identify all energy sources, draft a LOTO procedure using the facility's equipment-specific forms, and have a peer review it against OSHA 29 CFR 1910.147 requirements before instructor sign-off. · Each student produces a freehand as-built sketch of their assigned build station showing component locations, fastener access points, shaft alignments, and piping/conduit routing; the sketch is dimensioned using calipers and a steel rule and checked against actual hardware during a brief instructor walk-through. · Students create a PLC I/O list on a provided spreadsheet template, listing every input device (sensors, pushbuttons) and output device (motor starter coil, indicator lights) with address tags and descriptions, then cross-reference the list against the ladder logic printout provided to confirm completeness.
Materials: Project brief packet, OSHA 29 CFR 1910.147 reference card, facility LOTO tags and locks, blank equipment-specific LOTO procedure forms, steel rule, calipers, graph paper, pencils, laptop or desktop with spreadsheet software, PLC ladder logic printout, NCCER Industrial Maintenance Core and Level 1–4 curricula (as reference), MSSC CPT Safety module reference guide
Check: Instructor reviews LOTO procedure against a checklist derived from OSHA 29 CFR 1910.147; sketch is checked for all labeled subsystems and at least 80% dimensional accuracy; I/O list matches all physical devices with no omissions. Student must pass all three checks (no critical safety errors allowed, zero tolerance) before advancing to Lesson 2.

Practice check8

Answer each question, then check it. Nothing is recorded; this is your own practice.

NCCER Industrial Maintenance — Safety
1. According to OSHA 29 CFR 1910.147, which step must be performed LAST in a lockout/tagout procedure before maintenance work begins?
NCCER Industrial Maintenance — Preventive Maintenance and Inspection
2. A student's as-built sketch labels the motor, pump, and conduit routing but omits the bearing housing locations and the belt-drive center-to-center distance. What is the most significant consequence of this omission during a maintenance event?
NCCER Industrial Maintenance — Safety
3. Which of the following energy sources MUST be listed in the LOTO procedure for a motor-driven pump even after the main electrical disconnect has been opened and locked?
NCCER Industrial Maintenance — Electrical — PLC Fundamentals
4. On a PLC I/O list, a normally closed (NC) Stop pushbutton is wired to address I:0/1. In the ladder logic, that address appears as a normally closed contact instruction. What does this wiring and programming combination achieve when the Stop button is NOT pressed?
NCCER Industrial Maintenance — Safety
5. A peer review of a student's LOTO procedure finds that the procedure lists the main electrical disconnect but does not identify the 24 V DC PLC power supply as a separate energy source. Under OSHA 29 CFR 1910.147, this omission is:
NCCER Industrial Maintenance — Tools and Equipment; MSSC CPT — Quality Practices
6. When measuring a shaft diameter with calipers for an as-built sketch, which practice produces the most reliable recorded value?
NCCER Industrial Maintenance — Electrical — PLC Fundamentals
7. The capstone project requires a PLC I/O list that is cross-referenced against the ladder logic printout. The purpose of this cross-reference is to:
MSSC CPT — Safety and Health; NCCER Industrial Maintenance — Safety
8. Which of the following items is a required element of a Job Hazard Analysis (JHA) for the capstone motor-pump assembly?
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