Where a potential for shorting violation of minimum electrical clearance exists between conductive component bodies, at least 1 of the bodies shall be protected by an insulator.
Target – Class 1,2,3 • Uninsulated metallic component insulated from underlying
circuitry with insulating material. • Uninsulated metallic clips and holding devices used to
secure components insulated from underlying circuitry with insulating material.
1 2
3
3
4
Figure 7-54
1. Conductive patterns 2. Metallic mounting clip
3. Insulation material 4. Clearance
7.1.9 Component Mounting – Conductive Cases
7.2 Component Securing
7-23 IPC-A-610F
July 2014
7.2.1 Component Securing – Mounting Clips
Acceptable – Class 1,2,3 • The clip makes contact to both sides of the component, see
Figure 7-55-A. • The component is mounted with the center of gravity within
the confines of the clip, see Figure 7-55-B,C. • The end of the component is flush with or extends beyond
the end of the clip, see Figure 7-55-C. • Spacing between land and uninsulated component body
does not violate minimum electrical clearance.
A
B
C
1 2
3
4
Figure 7-55
1. Clip 2. Nonsymmetrical body
3. Top view 4. Center of gravity
7.2.1 Component Securing – Mounting Clips cont.
7-24 IPC-A-610F
July 2014
Defect – Class 1,2,3 • Spacing between land and uninsulated component body is
less than minimum electrical clearance, Figure 7-56. • Uninsulated metallic clip or holding device is not insulated
from underlying circuitry. • Clip does not restrain component, Figure 7-57-A.
• Component center or center of gravity not within the con- fines of the clip, Figure 7-57-C.
The criteria below shall be used when staking is required and criteria are not provided on the drawing. These criteria do not apply
to SMT components see 8.1. Visual inspection of staking may be performed without magnification. Magnification from 1.75X to 4X may be used for referee pur-
poses. Refer to adhesive manufacturer’s guidelines for curing requirements.
Figure 7-56
A
B
C
Figure 7-57
7.2.1 Component Securing – Mounting Clips cont.
7.2.2 Component Securing – Adhesive Bonding
7-25 IPC-A-610F
July 2014
These criteria are the same for sleeved or unsleeved components, see exception below for glass bodied components. Acceptable – Class 1,2,3
• Continuous adhesion fillet to the mounting surface and com- ponent body.
• Adhesive is cured. • No gapseparationcrack between staking and attachment
surfaces. • On a horizontally mounted component the staking material:
– Adheres to component for at least 50 of its length L. – The buildup of staking material does not exceed 50 of
the component diameter. – Minimum of 25 component diameter D on 1 side and
approximately centered on component body. • On a vertically mounted component:
– The staking material beads are continuous for least 25 of the component length L with slight flow of staking
material under the component body, see Figure 7-58-1. – The staking material adheres to the component:
• For at least 3 beads spaced approximately evenly around the circumference OR
• For a minimum of at least 50 of the component cir- cumference.
• Glass bodied components are sleeved, when required, prior to staking material attachment.
– Adhesives, e.g., staking, bonding, do not contact an unsleeved area of a sleeved glass body component.
– Sleeved component has staking material applied to both sides from 50 to 100 of the component length and
minimum 25 of component height. • Multiple vertically mounted components:
– Staking material adheres to each component for at least 50 of its length L, and the adhesion is continuous
between components, see Figure 7-59-2. – The staking material adheres to each component for a
minimum 25 of its circumference, see Figure 7-59-1.
L
25 D Max 50 D
D 50 L
L 50 L
1 2
3
Figure 7-58
1. Adhesive 2. Top view
