CIT Acceptability of Electronic Assemblies 2 — Questions and Answers
Question 1: According to IPC-A-610, what is the minimum acceptable solder fill in a through-hole barrel for Class 2 assemblies?
- 25%
- 50% (Correct answer)
- 75%
- 100%
Correct answer: 50%
IPC-A-610 requires a minimum of 50% barrel fill for Class 2 through-hole solder joints.
Question 2: Which condition describes a through-hole lead that protrudes beyond the maximum allowable length after soldering?
- Acceptable condition
- Process indicator
- Defect condition (Correct answer)
- Target condition
Correct answer: Defect condition
Excessive lead protrusion beyond the maximum specified length is a defect condition per IPC-A-610.
Question 3: A through-hole component's lead is not visible through the solder in the barrel on a Class 3 assembly. This is classified as:
- Target condition
- Acceptable condition
- Process indicator
- Defect (Correct answer)
Correct answer: Defect
For Class 3, the component lead must be discernible through the solder; if not visible, it is a defect.
Question 4: What term in IPC-A-610 describes a condition that does not meet the target but still meets the minimum requirements for reliability?
- Defect
- Process indicator
- Acceptable condition (Correct answer)
- Nonconformance
Correct answer: Acceptable condition
An 'acceptable condition' meets minimum performance requirements even if it does not match the ideal target.
Question 5: Per IPC-A-610, which class of product has the most stringent acceptability requirements for electronic assemblies?
- Class 1
- Class 2
- Class 3 (Correct answer)
- Class 4
Correct answer: Class 3
Class 3 represents high-reliability products with the most stringent requirements under IPC-A-610.
Question 6: A cold solder joint on a through-hole connection typically appears:
- Bright and shiny with a concave meniscus
- Dull and grainy with a rough surface texture (Correct answer)
- Smooth and flat with no wetting
- Clear and transparent under magnification
Correct answer: Dull and grainy with a rough surface texture
Cold solder joints have a dull, grainy appearance caused by insufficient heat during soldering.
Question 7: Which IPC-A-610 condition requires mandatory disposition but does not automatically make the assembly scrap?
- Target condition
- Acceptable condition
- Process indicator (Correct answer)
- Defect
Correct answer: Process indicator
A process indicator requires evaluation and disposition but does not automatically reject the assembly.
CIT Acceptability of Electronic Assemblies 2
According to IPC-A-610, what is the minimum acceptable solder fill in a through-hole barrel for Class 2 assemblies?