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newSchoolWorks.com › VoTechWorks › Manufacturing & Marine › Robotics / Mechatronics › Certification Exam Preparation: FANUC CERT, Siemens Mechatronics L1, and PMMI Mechatronics › Lesson 1
MFG-MECH15-10 · Lesson 1 · 24 clock hours · theory

PMMI Mechatronics Written Exam Review: All Eight Test Areas

Objective. Given timed practice sets drawn from all eight PMMI test areas, students will correctly answer at least 75% of questions in each area and identify personal weak domains for targeted study.

⚠ 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.

PMMI Mechatronics Written Exam Review: All Eight Test Areas

The PMMI Mechatronics certification is issued by PMMI, The Association for Packaging and Processing Technologies. You earn it by passing individual knowledge exams across eight test areas. Each exam costs approximately $125, so you want to pass on the first attempt. This lesson walks through the core concepts in every area, flags the formulas you must apply fluently, and points out the safety standards most likely to appear as scenario questions.

Fluid Power

Fluid power covers pneumatic and hydraulic systems. The two calculations you must know are cylinder force and hydraulic speed.

Pressure acts equally in all directions (Pascal's law). Understand component symbols: directional control valves (2/2, 4/2, 4/3), pressure relief valves, flow control valves, cylinders, and FRL (filter-regulator-lubricator) units. Know the difference between meter-in and meter-out speed control. Safety: machine guarding of pinch points on cylinders falls under OSHA 1910.212, and hydraulic energy must be isolated using lockout/tagout procedures per OSHA 29 CFR 1910.147 before any maintenance.

Industrial Electricity 1 and 2

Electricity 1 covers DC fundamentals: Ohm's law (V = IR), power (P = VI = I²R = V²/R), and series/parallel circuits. In a series circuit, current is the same throughout; resistance adds directly. In a parallel circuit, voltage is the same across branches; total current is the sum of branch currents.

Electricity 2 moves into AC systems, transformers, capacitors, and inductors. Know how to read a multimeter for voltage, current, and resistance, and understand continuity testing.

Safety is central to both exams. NFPA 70E governs electrical safety in the workplace. Key concepts: shock protection boundaries (limited and restricted approach), arc-flash boundaries, the requirement for an energized electrical work permit when working on live circuits above defined thresholds, and the procedure to verify absence of voltage with a properly rated meter before any contact. Appropriate PPE (arc-rated clothing, voltage-rated gloves, face shields) is selected based on the incident energy level. NFPA 79 covers the electrical standard for industrial machinery — it governs control panel wiring, conductor sizing, disconnecting means, and grounding on machine tools.

Mechanical Components 1 and 2

Mechanical Components 1 addresses gears, pulleys, belts, and chains. The ratio relationships are:

Mechanical Components 2 covers bearings, couplings, shafts, keys, and precision measurement tools (vernier calipers, micrometers, dial indicators). Understand proper lubrication intervals, interference fits, and alignment procedures. Machine guarding of rotating parts is required by OSHA 1910.212 — all belts, chains, gears, and exposed rotating shafts must be guarded.

Motor and Motor Controls

This area covers AC induction motors, DC motors, and the control circuits that start, stop, and protect them.

Synchronous speed: Ns = 120f ÷ P, where f = frequency (Hz) and P = number of poles.

Slip = (Ns − Nrotor) ÷ Ns × 100%. A typical induction motor runs at 2–5% slip.

Torque from horsepower: T (lb·ft) = HP × 5252 ÷ RPM.

Know the ladder-logic symbols for motor starters: normally open (NO) and normally closed (NC) contacts, overload relay contacts, and coils. Understand across-the-line starting, reduced-voltage starting, and variable frequency drives (VFDs). Thermal overloads and fuses protect against overcurrent. Lockout/tagout (OSHA 1910.147) must be applied before working on any motor or control panel.

Programmable Logic Controllers 1 and 2

PLC 1 covers basic hardware, discrete I/O wiring, and introductory ladder diagram programming: examine-if-closed (XIC) and examine-if-open (XIO) instructions, output coils, timers (TON, TOF), and counters (CTU, CTD).

PLC 2 advances to comparison instructions, math instructions, analog I/O, and HMI basics. Analog signals use the 4–20 mA current loop or 0–10 V standard. Scaling formula:

Scaled value = [(Raw − Raw_min) ÷ (Raw_max − Raw_min)] × (EU_max − EU_min) + EU_min

IEC 61131-3 defines five PLC programming languages: Ladder Diagram (LD), Function Block Diagram (FBD), Structured Text (ST), Sequential Function Chart (SFC), and Instruction List (IL). Industrial networks such as EtherNet/IP, PROFINET, and Modbus are common on modern systems.

Using Your Gap-Analysis Tracker

After each 25-question practice set, score yourself immediately and record the percentage in your personal readiness tracker. Any area below 75% requires a small-group drill session. During drill, teach the concept back to a peer — explaining forces you to locate the exact gap in your understanding. Then complete the 15-question re-check quiz. Your instructor will review the tracker at the end of this lesson and assign additional resources for any area that still falls short. Target 75% or higher in every domain before sitting a live PMMI exam.

Key terms10

Cylinder forceThe linear pushing or pulling force produced by a fluid power cylinder, calculated as pressure (psi) multiplied by piston area (in²), expressed in pounds.
Hydraulic speedThe linear velocity of a hydraulic cylinder's rod, calculated as flow rate (gal/min) × 231 divided by piston area (in²), expressed in in/min.
Synchronous speed (Ns)The theoretical no-load rotational speed of an AC induction motor's magnetic field, given by Ns = 120f ÷ P, where f is supply frequency in hertz and P is the number of poles.
SlipThe difference between synchronous speed and actual rotor speed, expressed as a percentage of synchronous speed; typically 2–5% in a loaded induction motor.
4–20 mA current loopA standard analog signal format used in industrial instrumentation where 4 mA represents the minimum process value and 20 mA represents the maximum, allowing fault detection when current falls below 4 mA.
NFPA 70EThe National Fire Protection Association standard for electrical safety in the workplace; establishes shock and arc-flash protection boundaries, PPE requirements, and the energized electrical work permit process.
OSHA 29 CFR 1910.147The federal regulation governing control of hazardous energy (lockout/tagout); requires that energy sources be isolated and locked out before employees perform servicing or maintenance on equipment.
IEC 61131-3The international standard that defines five programming languages for programmable logic controllers: Ladder Diagram, Function Block Diagram, Structured Text, Sequential Function Chart, and Instruction List.
Gear ratioThe ratio of driver gear teeth to driven gear teeth; determines the relationship between input and output speed and torque — higher ratio means lower output speed and higher output torque.
NFPA 79The National Fire Protection Association electrical standard for industrial machinery; governs control panel construction, conductor sizing, disconnecting means, and grounding for machine tools and automated equipment.

Worked examples4

1. A hydraulic cylinder has a piston diameter of 3 inches and operates at a supply pressure of 1,500 psi. What is the maximum push force the cylinder can produce?
  1. Step 1 – Calculate piston area. Area = π × r² = π × (1.5 in)² = π × 2.25 = 7.069 in² (round to 7.07 in²).
  2. Step 2 – Apply the cylinder force formula: Force = Pressure × Area = 1,500 psi × 7.07 in².
  3. Step 3 – Multiply: 1,500 × 7.07 = 10,605 lb.
Answer: The cylinder produces approximately 10,605 lb of push force.
2. An AC induction motor is connected to a 60 Hz supply and has 4 poles. Its nameplate full-load speed is 1,740 RPM. Calculate (a) synchronous speed and (b) slip at full load.
  1. Step 1 – Synchronous speed: Ns = 120f ÷ P = 120 × 60 ÷ 4 = 7,200 ÷ 4 = 1,800 RPM.
  2. Step 2 – Slip = (Ns − Nrotor) ÷ Ns × 100% = (1,800 − 1,740) ÷ 1,800 × 100%.
  3. Step 3 – Slip = 60 ÷ 1,800 × 100% = 0.0333 × 100% = 3.33%.
Answer: (a) Synchronous speed = 1,800 RPM. (b) Full-load slip = 3.33%.
3. A PLC analog input module reads a 4–20 mA signal from a pressure transmitter ranged 0–200 psi. The current signal is 12 mA. What pressure does this represent?
  1. Step 1 – Identify the raw range: Raw_min = 4 mA, Raw_max = 20 mA. Engineering unit range: EU_min = 0 psi, EU_max = 200 psi.
  2. Step 2 – Apply the scaling formula: Scaled value = [(Raw − Raw_min) ÷ (Raw_max − Raw_min)] × (EU_max − EU_min) + EU_min.
  3. Step 3 – Substitute values: [(12 − 4) ÷ (20 − 4)] × (200 − 0) + 0 = [8 ÷ 16] × 200 = 0.5 × 200 = 100 psi.
Answer: A 12 mA signal corresponds to 100 psi.
4. A driving gear has 20 teeth and meshes with a driven gear having 60 teeth. The driving gear rotates at 900 RPM. What is the output speed and how does torque change?
  1. Step 1 – Calculate gear ratio: Ratio = Driver teeth ÷ Driven teeth = 20 ÷ 60 = 1:3 (the driven gear turns 3 times slower).
  2. Step 2 – Output speed = Input speed ÷ Ratio = 900 RPM ÷ 3 = 300 RPM.
  3. Step 3 – Because speed decreases by a factor of 3 and assuming no friction losses, torque increases by the same factor of 3 (output torque = input torque × 3).
Answer: Output speed = 300 RPM; output torque is three times the input torque.

The math in this lesson3

Learners compute gear output speed from a 20:60 tooth ratio and the matching torque change.
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Brush up in the math halls at newSchoolWorks.com:
In class: Structured content review sessions, one per PMMI test area in sequence—Fluid Power; Industrial Electricity 1 and 2; Mechanical Components 1 and 2; Motor and Motor Controls; PLC 1 and 2—with an instructor-led worked-example walk-through of representative problems for each area, including formula application (cylinder force, hydraulic speed, Ohm's law, 4–20 mA scaling, gear and pulley ratios) and safety-standard scenario questions (NFPA 79, OSHA 1910.212, NFPA 70E). · Students complete a 25-question timed written practice set immediately after each content review session, mark their own answers against the key using a gap-analysis score sheet, and enter results into a personal readiness tracker that highlights any area scoring below 75%. · Small-group drill sessions on lowest-scoring domains identified by the tracker: students teach-back concepts to peers, work additional practice problems at whiteboards, and receive instructor correction before a second 15-question re-check quiz for each deficient area.
Materials: PMMI Mechatronics study guides for all eight test areas; instructor-authored practice question banks aligned to each test domain; formula reference card (Ohm's law, power, series/parallel, Ns = 120f/P, slip, T = hp × 5252/rpm, cylinder force, hydraulic speed, 4–20 mA scaling, gear/pulley ratios); NFPA 70E, NFPA 79, OSHA 1910.147 and 1910.212 quick-reference summaries; individual gap-analysis score sheets; whiteboards; calculators
Check: Personal readiness tracker reviewed by instructor at end of lesson; students must demonstrate 75% or higher on each PMMI area's practice set or re-check quiz before moving forward; instructor documents any remaining gaps and assigns targeted review resources

Practice check8

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

Fluid Power
1. A pneumatic cylinder with a 2-inch diameter bore is supplied at 100 psi. What is the approximate push force?
Fluid Power
2. Before removing a hydraulic power unit for repair, a technician must isolate all energy sources. Which regulation specifically requires a written lockout/tagout procedure and the use of personal locks?
Industrial Electricity 1
3. A technician needs to measure voltage on an energized 480 V panel to verify a circuit fault before applying lockout. Which NFPA standard governs the required PPE and the arc-flash boundary for this task?
Industrial Electricity 1
4. Three resistors of 10 Ω, 20 Ω, and 30 Ω are connected in series across a 120 V source. What is the total current in the circuit?
Motor and Motor Controls
5. A 6-pole AC induction motor is powered by a 60 Hz supply. What is its synchronous speed?
Mechanical Components 1
6. A driving pulley has a diameter of 4 inches and rotates at 1,200 RPM. It drives a second pulley with an 8-inch diameter via a V-belt. What is the speed of the driven pulley?
Programmable Logic Controllers 1
7. In a PLC ladder diagram, a Timer On-Delay (TON) instruction is programmed with a preset of 5 seconds. The rung enabling the timer goes TRUE. When does the timer's Done (DN) bit energize?
Programmable Logic Controllers 2
8. A PLC analog input module accepts 4–20 mA signals and is connected to a flow transmitter ranged 0–100 gallons per minute. If the transmitter sends 20 mA, what flow rate does the PLC read?
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