CPL Key Systems & Key Control 3 — Questions and Answers
Question 1: What does 'total position change' (TPC) refer to in key system design?
- The total number of master key levels
- The number of unique change keys possible in a system (Correct answer)
- The maximum depth a cut can be made on any key
- The number of pins in the deepest pin stack
Correct answer: The number of unique change keys possible in a system
Total position change (TPC) is the total number of unique individual change key combinations available in a master key system.
Question 2: A key system that uses rotating elements rather than traditional pin tumblers for higher security is best described as a:
- Wafer tumbler system
- Disc detainer system (Correct answer)
- Lever tumbler system
- Pin tumbler system
Correct answer: Disc detainer system
Disc detainer locks use rotating disc elements that must align precisely, offering high pick resistance and key control.
Question 3: In key system terminology, what is a 'keyway'?
- The corridor leading to a secured door
- The profile cut into the cylinder plug that accepts a specific key blade shape (Correct answer)
- The depth specification for key cuts
- The angle of the key bow
Correct answer: The profile cut into the cylinder plug that accepts a specific key blade shape
The keyway is the shaped opening in the cylinder plug that matches the corresponding key blank profile, controlling which blanks can enter.
Question 4: What is the function of a 'control key' in a proprietary cylinder system?
- It opens every lock in the facility
- It allows removal of the core from the cylinder for rekeying (Correct answer)
- It resets the master wafers inside the lock
- It is used only in emergencies by fire departments
Correct answer: It allows removal of the core from the cylinder for rekeying
A control key is used in interchangeable core (IC) systems to remove or insert the core, enabling rapid rekeying without tools.
Question 5: Which ANSI/BHMA grade rating indicates the highest performance level for locks used in key control systems?
- Grade 3
- Grade 2
- Grade 1 (Correct answer)
- Grade 4
Correct answer: Grade 1
ANSI/BHMA Grade 1 is the highest rating, indicating heavy-duty commercial performance and the strongest security standards.
Question 6: In a key system, what does 'masting' refer to?
- Cutting a key to its deepest possible bitting
- Adding an additional master wafer or pin to a lock so it operates on a master key (Correct answer)
- Installing a new keyway profile across all cylinders
- Replacing all change keys with a single universal key
Correct answer: Adding an additional master wafer or pin to a lock so it operates on a master key
Masting a lock involves adding master wafers or pins so it can be operated by both its change key and a master key.
Question 7: What is the purpose of a 'key cabinet' in a key control program?
- To display the facility's key collection for identification
- To securely store and organize keys with controlled access and audit capability (Correct answer)
- To hold duplicate keys for all employees
- To store key-cutting equipment and blanks
Correct answer: To securely store and organize keys with controlled access and audit capability
A key cabinet provides secure, organized storage for keys with access logging to enforce accountability in a key control program.
CPL Key Systems & Key Control 3
What does 'total position change' (TPC) refer to in key system design?