S9407-AB-HBK-010 Datasheet, PDF (129/276 Pages) Glenair, Inc. – HANDBOOK OF SHIPBOARD ELECTROMAGNETIC SHIELDING PRACTICES

S9407-AB-HBK-010, Rev. 2
Example B
A 60-Hz power cable, type TSGU-100, is to be routed near an active/passive sonar cable,
type DSS-3. The sonar operates passively in the passband 300 Hz to 10 kHz. The DSS-3 cable
connects the transducers to the preamplifiers, and the preamplifiers have a design performance
sensitivity of -173 dBV. Due to the physical layout of equipment there is a spacing restriction of 5
inches on these cables. This DSS-3 cable is a dual-function cable, but in this example only the
receiving function will be considered.
PROCEDURE
1
STEP NO.
RESULTS AND
CALCULATIONS
1
R1-4 (radiator)
2
S4-1 (susceptor)
3
13 inches (spacing w/o
shielding)
4
5 inches (available spacing)
5
S(dB) = 30 dB
6
V₃(dBV) = -173 + 30
= -143
7
2 (new group number)
8
10 inches (spacing with
shielding)
9
5 inches (available spacing)
10
Spacing with susceptor and
radiator shielded
NOTES
Table 6-1 and figure 6-1 (sheet 1)
Table 6-1, figure 6-4 (sheet 1), and figure 6-5
(note 3). V1(dBV) = -173.
Figure 6-6. Intersection of coordinates R1-4
and S4-1.
Installation spacing restriction. Required
spacing in step 3 is greater than available
spacing in step 4; shielding of susceptor is
required.
Figure 6-7. Flexible conduit at 300 Hz
(passband is 300 Hz to 10 kHz).
V₃(dBV) = V₁(dBV) + S(dB)
Figure 6-5 (Note 4).
Cable designation is S4-2.
Figure 6-6. Intersection of coordinates R1-4
and S4-2.
Required spacing in step 8 is less than
available spacing in step 4. Radiator and
susceptor require shielding.
Determine by repeating steps 5 through 9.
CHANGE 1 of Revision 2
6-16