MRP Material Requirements Planning Fundamentals 4 — Questions and Answers
Question 1: In a Manufacturing Resource Planning (MRP II) system, which module extends basic MRP by incorporating capacity constraints?
- Capacity Requirements Planning (CRP) (Correct answer)
- Distribution Requirements Planning (DRP)
- Master Scheduling
- Demand Management
Correct answer: Capacity Requirements Planning (CRP)
CRP uses MRP-generated planned and released orders to calculate load on each work center and compares it to available capacity.
Question 2: A 'phantom' assembly in a BOM is characterized by:
- A subassembly that is built and stocked before final assembly
- A transient assembly that passes through inventory without being stocked (Correct answer)
- A component with zero lead time and infinite availability
- An obsolete part retained for historical reference
Correct answer: A transient assembly that passes through inventory without being stocked
Phantom assemblies are typically built and consumed immediately in the same production run, so MRP is configured to pass demand through them rather than stock them.
Question 3: Which lot-sizing rule orders exactly the quantity needed in each time period, resulting in zero ending inventory when demand is met?
- Fixed Order Quantity (FOQ)
- Lot-for-Lot (L4L) (Correct answer)
- Period Order Quantity (POQ)
- Economic Order Quantity (EOQ)
Correct answer: Lot-for-Lot (L4L)
Lot-for-Lot orders precisely the net requirement for each period, minimizing carrying costs by avoiding excess inventory between periods.
Question 4: When an MRP system generates an 'expedite' exception message, it means:
- A planned order should be rescheduled to an earlier date to avoid a shortage (Correct answer)
- An existing order should be de-expedited and pushed to a later period
- Safety stock has been consumed and must be replenished immediately
- A supplier has confirmed early delivery of an outstanding order
Correct answer: A planned order should be rescheduled to an earlier date to avoid a shortage
An expedite message alerts the planner that a scheduled receipt needs to be moved earlier because the current timing will result in a projected shortage.
Question 5: The 'available to promise' (ATP) quantity is most directly linked to which MRP input?
- On-hand inventory and scheduled receipts versus actual customer orders (Correct answer)
- Gross requirements and safety stock targets
- BOM lead times and lot sizing rules
- Forecast accuracy and demand variability
Correct answer: On-hand inventory and scheduled receipts versus actual customer orders
ATP is calculated by comparing uncommitted supply (on-hand plus scheduled receipts) against actual customer orders to determine what can still be promised.
Question 6: In MRP, a 'firm planned order' (FPO) differs from a regular planned order because:
- It is automatically adjusted by the MRP regeneration run
- It is frozen and not automatically changed by the MRP system (Correct answer)
- It has been physically released to the shop floor or supplier
- It carries a higher order priority than scheduled receipts
Correct answer: It is frozen and not automatically changed by the MRP system
A firm planned order is manually fixed by the planner so that MRP regeneration will not automatically reschedule or cancel it, preserving intentional planning decisions.
Question 7: Which of the following best describes 'regenerative MRP'?
- A continuous, real-time update of MRP records as transactions occur
- A complete recalculation of all MRP records from scratch on a periodic basis (Correct answer)
- An incremental update that only replans items affected by recent changes
- A simulation run used to evaluate what-if planning scenarios
Correct answer: A complete recalculation of all MRP records from scratch on a periodic basis
Regenerative MRP reprocesses the entire MRP database from the MPS downward on a scheduled basis (typically weekly), ensuring all records reflect the current plan.
In a Manufacturing Resource Planning (MRP II) system, which module extends basic MRP by incorporating capacity constraints?