5.4.4 MAXIMUM ALLOWABLE PSD LEVEL IN LATERAL VIBRATION
The lateral vibration is as critical as perpendicular vibration. The
problem is usually with large mass axial lead or metal can type parts. When
vibration is applied in a lateral direction, the partís weight will cause it
to rock back and forth, which can result in lead wire fatigue. It may be
difficult to compensate for lateral vibration if large parts are used.
Therefore, large axial lead parts should be bonded to the PWB. If this cannot
be achieved, the following technique shall be followed to determine the
maximum allowable PSD input level. There are two different techniques, one for
axial lead parts and the other for metal can type parts. Metal clips and wire
straps have proven ineffective for holding large axial leaded components
unless combined with RTV or other bonding agent.