Maintenance & Mechanics Flashcards

A maintenance log entry reads: 'Replaced conveyor belt drive motor on Unit 4B. Motor model: 3HP-208V-60Hz. Installation date: 03/14/2026. Torque spec: 45 ft-lbs. Completed by: Tech J. Harmon.' Which field contains an error if the facility runs on 480V three-phase power?

Answer: Motor model voltage rating

The motor is rated 208V but the facility operates on 480V, making the voltage rating an error that would cause equipment failure.

A work order states: 'Lubricate all conveyor chain links using SAE 30 oil every 500 hours.' The equipment manual specifies chain lubrication every 250 hours with ISO 220 gear oil. What is the error in the work order?

Answer: Both the interval and lubricant type

Both the lubrication interval (500 vs. 250 hours) and the lubricant type (SAE 30 oil vs. ISO 220 gear oil) are incorrect.

A parts request form lists: 'Item: Conveyor roller bearing. Part #: 6205-2RS. Qty: 12. Unit cost: $4.80. Total: $57.60.' What is the arithmetic error in this form?

Answer: No arithmetic error — $57.60 is correct

12 × $4.80 = $57.60 is mathematically correct, so there is no arithmetic error on this form.

A safety inspection checklist entry reads: 'Fire extinguisher Station 7: Last inspected 11/2025. Next inspection due: 11/2027.' If USPS policy requires annual fire extinguisher inspections, what is the error?

Answer: The next inspection due date should be 11/2026, not 11/2027

Annual inspections mean the next due date should be 12 months after the last, so 11/2026, not 11/2027.

A repair record states: 'Flat belt replaced on sorter #3. Belt dimensions: 6 inches wide × 48 feet long. Tension set to 120 PSI. Belt speed: 250 FPM.' The technician's manual states belt tension should be 80–100 PSI. What error is present?

Answer: Belt tension exceeds the specified range

120 PSI exceeds the allowable tension range of 80–100 PSI, indicating the belt was over-tensioned.

A maintenance schedule shows Machine A receives a full inspection every 1,000 hours. The machine's current meter reads 7,340 hours, and the last full inspection was at 6,500 hours. According to the schedule, is an inspection overdue?

Answer: No — the next inspection is due at 7,500 hours and the meter reads 7,340

6,500 + 1,000 = 7,500 hours; since the meter reads 7,340, the next inspection is not yet due.

A work order requests replacement of a 15-amp circuit breaker with a 20-amp breaker because 'the 15-amp breaker keeps tripping.' What is the likely error in this corrective action?

Answer: Increasing breaker amperage without diagnosing the root cause may create a fire hazard

Replacing a breaker with a higher-rated one without finding the cause of tripping can allow unsafe current levels, creating a fire hazard.