CRL case studies
CRL · Put your knowledge to work in context.
This independent study page provides practice for CRL. Its editorial learning areas include Locksmith foundations: authorized service, compatible hardware and verified function. The questions develop subject knowledge and application through worked reasoning, distinctions between competing answers, and practical scenarios. Study the relevant guide before attempting a mixed set, then explain the evidence or calculation that supports each answer. Topics on this exam: Locksmith foundations: authorized service, compatible hardware and verified function. The CRL case studies are 4 cases and about 744 words.
1Similar blanks and different locating references
An authorized locksmith training exercise presents two visually similar key blanks and an instructor-owned demonstration cylinder. One blank uses a shoulder reference, while the other uses a tip reference under its equipment data. A trainee proposes using the same machine position simply because both blades fit partway into the keyway. The available drawings show the intended profile and locating dimensions, but the exercise supplies no permission to modify a customer lock or override a restricted-key arrangement.
184 words, under 1 min2A door that closes but does not latch reliably
An authorized service request concerns a door that sometimes reaches the frame without latching. A prior worker adjusted the closer repeatedly, but the complaint returned. Observations suggest possible hinge wear, strike misalignment and changing air pressure. The door also has an egress function that must remain available under its approved arrangement.
189 words, under 1 min3A supplied access-control voltage model
A classroom exercise models a compatible direct-current door-control component on an isolated training board. The supplied source voltage is 24 volts, load current is 0.5 ampere and total path resistance is 4 ohms. For this exercise only, the component information states an acceptable terminal range of 20 to 26 volts. A trainee compares the nominal source voltage with the range and ignores the path resistance.
188 words, under 1 min4Theoretical combinations and a key-control plan
A theoretical classroom model gives a training key five independent cut positions and six allowable depth values at each position. The task explicitly ignores adjacent-cut restrictions, reserved combinations and other manufacturer constraints for the arithmetic portion. A trainee multiplies five by six and claims there are thirty combinations. Another correctly finds a larger theoretical number but treats every mathematical sequence as a suitable key in an actual master-key system.
183 words, under 1 min