CIT Requirements for Soldered Electrical and Electronic Assemblies 2

Question 1

According to IPC J-STD-001, what is the minimum solder coverage required on the lead end for Class 2 through-hole solder joints?

Accepted Answer

100%

Answer

IPC J-STD-001 requires 100% solder coverage on the lead end (top of the board) for Class 2 through-hole solder joints.

Question 2

Which flux type classification per J-STD-004 does NOT require cleaning after soldering when used within its activity level limits?

Accepted Answer

RO (Rosin)

Answer

RO (Rosin) flux residues are generally considered non-corrosive and do not require cleaning when activity levels are within specified limits.

Question 3

What is the purpose of the 'wetting angle' measurement in solder joint evaluation?

Accepted Answer

To assess how well the solder has bonded and spread on the metal surface

Answer

The wetting angle (contact angle) indicates how well the solder has flowed and bonded to the base metal, reflecting the quality of the metallurgical bond.

Question 4

Per IPC J-STD-001, a 'cold solder joint' is characterized by which visual appearance?

Accepted Answer

Dull, grainy, or frosted surface indicating incomplete fusion

Answer

Cold solder joints appear dull, grainy, or frosted because the solder did not reach proper reflow temperature, resulting in poor tin-lead or tin alloy crystallization.

Question 5

What does the IPC J-STD-001 term 'minimum annular ring' refer to in PCB fabrication requirements?

Accepted Answer

The copper remaining between the drilled hole edge and the outer edge of the pad

Answer

The annular ring is the copper pad material remaining between the drilled hole and the outer edge of the pad, ensuring adequate mechanical and electrical connection.

(CIT) Certified IPC Trainer Practice Test

(CIT) Certified IPC Trainer Practice Test

CIT Requirements for Soldered Electrical and Electronic Assemblies 2