IPC-TM-650 EN 2022 试验方法1.pdf - 第296页

Note: Note: Figure 4 Bow Measurement T ouching Datum Surface HIGHEST POINT measured as R or R L W T ouching Datum Surface IPC-TM-650 Page 3 of 5

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Figure 3 External Measurements
L
D
W
IPC-TM-650
Page 2 of 5
Note:
Note:
Figure 4 Bow Measurement
Touching Datum
Surface
HIGHEST POINT
measured as R or R
L
W
Touching Datum
Surface
IPC-TM-650
Page 3 of 5
Figure 5 Measurement of Twist
R
A
C
D
B
R = Highest
Point of Board
Shim under raised
corner of A.
B, C, and D touching
Datum Surface. Only
one corner may be
physically restrained.
Figure 6 Sample Placement
R2 Lowest
Corners
R2 R2
R1
Raised Parallel
Surfaces
IPC-TM-650
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