WALMART MAINTENANCE Preventive Maintenance 5 — Questions and Answers
Question 1: Why should electrical equipment be de-energized and locked out before performing preventive maintenance tasks that involve internal components?
- To save electricity during the PM process
- To prevent accidental energization that could cause injury or equipment damage (Correct answer)
- Because PM cannot be done while equipment is warm
- To allow the technician to reset error codes
Correct answer: To prevent accidental energization that could cause injury or equipment damage
Lockout/tagout (LOTO) prevents unexpected energization during internal PM tasks, protecting the technician from electrical shock or entanglement with moving parts.
Question 2: A quarterly PM task requires calibrating a digital temperature sensor in a cold storage area. What reference standard should the technician use for calibration?
- Another digital sensor of the same brand
- A NIST-traceable reference thermometer (Correct answer)
- The display temperature shown on the storage unit
- An estimated reading based on product feel
Correct answer: A NIST-traceable reference thermometer
Calibration must reference a NIST-traceable thermometer to ensure the sensor's accuracy is verifiable against a nationally recognized standard.
Question 3: When reviewing a PM schedule, the maintenance supervisor notes that several tasks are consistently pushed past their due date. What is the best corrective action?
- Delete overdue tasks from the schedule to reset compliance
- Analyze root causes (staffing, parts, time) and adjust resources or intervals accordingly (Correct answer)
- Extend all PM intervals to make compliance easier
- Assign all PM to a single technician to improve accountability
Correct answer: Analyze root causes (staffing, parts, time) and adjust resources or intervals accordingly
Consistent overdue tasks signal a systemic problem — root cause analysis identifies whether staffing, parts availability, or interval design needs adjustment.
Question 4: A maintenance technician notices during PM that a motor's exterior is significantly hotter than normal at the same load. Which tool can help confirm abnormal heat without stopping the motor?
- Digital multimeter
- Infrared thermometer or thermal camera (Correct answer)
- Clamp-on ammeter
- Vibration pen
Correct answer: Infrared thermometer or thermal camera
An infrared thermometer or thermal camera measures surface temperature remotely without stopping the motor, allowing real-time thermal comparison to baseline readings.
Question 5: Which of the following is an example of a leading indicator in a preventive maintenance program?
- Number of equipment breakdowns last quarter
- Percentage of PM tasks completed on time (Correct answer)
- Total repair cost for the past year
- Number of emergency work orders generated
Correct answer: Percentage of PM tasks completed on time
PM completion rate is a leading indicator because it predicts future reliability — high completion rates prevent breakdowns before they occur.
Question 6: A PM procedure requires replacing V-belts in pairs on a dual-belt drive. One belt shows cracking but the other looks fine. What is the correct action?
- Replace only the cracked belt to save cost
- Replace both belts at the same time (Correct answer)
- Apply belt dressing to the cracked belt and recheck in 30 days
- Increase belt tension to compensate for the cracked belt's weakness
Correct answer: Replace both belts at the same time
Matched belt sets must be replaced together because mixing a new and old belt causes uneven load sharing, accelerating wear on the new belt.
Question 7: After completing a preventive maintenance task on a piece of equipment, what is the final required step before returning the equipment to service?
- Notify the store manager immediately
- Remove all LOTO devices, test the equipment for proper operation, and complete the PM record (Correct answer)
- Leave a note on the equipment stating PM was performed
- Submit a work order for the next scheduled PM
Correct answer: Remove all LOTO devices, test the equipment for proper operation, and complete the PM record
The technician must remove all lockout devices, verify proper operation through a functional test, and complete the PM documentation before returning the equipment to service.
WALMART MAINTENANCE Preventive Maintenance 5
Why should electrical equipment be de-energized and locked out before performing preventive maintenance tasks that involve internal components?