S9407-AB-HBK-010 Datasheet, PDF (126/276 Pages) Glenair, Inc. – HANDBOOK OF SHIPBOARD ELECTROMAGNETIC SHIELDING PRACTICES

S9407-AB-HBK-010, Rev. 2
Spacing and shielding calculations are made by following the steps listed in procedures 1 and
2, paragraphs 6.8.1 and 6.8.2 respectively. The right-hand column lists sources of information, within
this section, that pertain to each step. Additional instructions are also given in the right-hand column
to assist in making the calculations.
6.8.1
Procedure 1 - Determining Cable-to-Cable Spacing and Shielding for
Radiators Versus Susceptors in Susceptor Categories S1, S2, and S4
STEP NO.
DETERMINE THE FOLLOWING
VALUES
1
Radiator category
Radiator group number
2
Susceptor category
(If cable type is in susceptor category)
Susceptor group number
3
Spacing requirement without shielding
4
Spacing restriction (Available spacing is
adequate or inadequate)
5
Conduit shielding effectiveness S(db)
6
V3(dBV)
7
New susceptor group number for cable
with shielding
8
Spacing requirement with one cable
shielded
9
Adequate shielding or inadequate
shielding
10
Spacing with susceptor and radiator
shielded
INFORMATION SOURCE OF
INSTRUCTION
Table 6-1.
Figures 6-1, 6-2, or 6-3.
Table 6-1.
Figures 6-4.
Table 6-5. (See note 3.)
Figure 6-6. Intersection of coordinates determined
in steps 1 and 2.
If step 4 is equal to or greater than required spacing
in step 3, available spacing is adequate; no
shielding is required.
If step 4 is less than required spacing in step 3,
available spacing is inadequate; shielding of
susceptor is required.
Figure 6-7. Use lowest frequency in passband of
equipment connected to susceptor.
V3(dBV) = V1(dBV) + S(dB). (See para 6.3k)
Figure 6-5. (See note 4.)
Figure 6-6. Intersection of coordinates determined
in steps 1 and 7.
If required spacing in step 8 is less than or equal to
available spacing in step 4, adequate shielding has
been provided.
If required spacing in step 8 is greater that available
spacing in step 4, shielding or both cables is
required.
Determine by repeating steps 5 through 9.
6-13