RTCA SC-135 and EUROCAE WG-14
Change Proposal Form
(One major comment per form.)
(Shaded blocks for committee use only.)
SC-135/WG-14 Paper Number: Date: 9-23-2008
DO-160F/ED-14F Section: 22
Rev G # AE2_G_P005
Author’s Name, Affiliation, and E-mail:
Paragraph:
Page:
Josh Bakk, Rockwell Collins, Inc.,
22.3.1
22-4
jdbakk@rockwellcollins.com
Summary of Change (25 words or less):
Add requirement to test unshielded cable bundles on equipment with shielded waveform set designators to
the appropriate waveforms.
Reason for Change (Justification):
Typically, a shielded waveform set designator is assigned to equipment with at least one shielded cable
bundle and all the cable bundles, including unshielded cable bundles, are tested to Waveform 1 or
Waveform 5A. Power and any other unshielded cable bundles tested to Waveform 1 or Waveform 5A
typically voltage limit, but don’t necessarily need to be retested with Waveform 2 or Waveform 4,
depending on the open circuit Voltage waveshape of the current generator. Either way, the wrong
Waveforms are applied because Table 22-1.2 forces a choice between shielded and unshielded. Rather
than complicate the Cable Bundle Test Requirements table, clarification should be made in the Waveform
Set Designators text. I think this is requirement, not guidance, material.
Revise From:
Waveform Set Designators (First and Third Characters)
Waveform sets A, C, E, G and J are applicable to equipment interconnected with wiring
installed within airframes or airframe sections where apertures, not structural resistance, are
the main source of induced transients as would be the case in an all-metal airframe. For the
same reasons, these waveform sets can also apply to equipment in airframes composed of
metal framework and composite skin panels, and to equipment in carbon fiber composite
(CFC) airframes whose major surface areas have been protected with metal meshes or foils.
Waveform sets B, D, F, H and K are applicable for equipment interconnected with wiring
installed within any airframe or airframe section when structural resistance is also a significant
source of induced transients, (i.e., carbon fiber composite structures). In these cases the wiring
is exposed to high structural voltages and redistributed lightning currents, which are
represented by Waveform 5A.
A and B are for pin injection tests.
C through F are for cable bundle single stroke tests.
G through K are for cable bundle single stroke, multiple stroke, and multiple burst tests.
Z indicates tests other than those specified in Table 22-1.1 or Table 22-1.2 were conducted,
such as the use of waveform set C, D, G, or H with shielded cables.
Proposal Page Number:
1 of 3
SC-135/ED-14 Change Proposal Form Rev G
Revise To:
Waveform Set Designators (First and Third Characters)
Waveform sets A, C, E, G and J are applicable to equipment interconnected with wiring
installed within airframes or airframe sections where apertures, not structural resistance, are
the main source of induced transients as would be the case in an all-metal airframe. For the
same reasons, these waveform sets can also apply to equipment in airframes composed of
metal framework and composite skin panels, and to equipment in carbon fiber composite
(CFC) airframes whose major surface areas have been protected with metal meshes or foils.
Waveform sets B, D, F, H and K are applicable for equipment interconnected with wiring
installed within any airframe or airframe section when structural resistance is also a significant
source of induced transients, (i.e., carbon fiber composite structures). In these cases the wiring
is exposed to high structural voltages and redistributed lightning currents, which are
represented by Waveform 5A.
Waveform sets E, F, J, and K are applicable for equipment with shielded interconnect wiring.
If unshielded cable bundles exist in Waveform set E, F, J, or K equipment, the applicable
unshielded Waveform Set shall be applied to the unshielded cable bundles. For example,
unshielded cable bundles in a Waveform set F EUT shall be tested to Waveforms 2, 3, and 4,
rather than Waveforms 3 and 5A. As another example, unshielded cable bundles in a
Waveform set J EUT shall be tested to Waveforms 2 and 3, rather than Waveforms 1 and 3.
Where EUT’s are tested to different waveform sets, the Category selected should correspond
to the category selected based on the shielding configuration (Example of additional words
needed).
A and B are for pin injection tests.
C through F are for cable bundle single stroke tests.
G through K are for cable bundle single stroke, multiple stroke, and multiple burst tests.
As
Modifiedtests
Text:other than
Z indicates
those specified in Table 22-1.1 or Table 22-1.2 were conducted, such
as the use ofWaveform
waveform
set
C,
G, orK H
shielded
sets E, F,D,
J, and
arewith
applicable
forcables.
equipment with shielded interconnect wiring.
If unshielded cable bundles exist in Waveform set E, F, J, or K equipment, the applicable
unshielded Waveform Set shall be applied to the unshielded cable bundles. For example,
unshielded cable bundles in a Waveform set F EUT shall be tested to Waveforms 2, 3, and 4,
rather than Waveforms 3 and 5A. As another example, unshielded cable bundles in a
Waveform set J EUT shall be tested to Waveforms 2 and 3, rather than Waveforms 1 and 3.
Where EUT’s are tested to different waveform sets, the Category selected should correspond
to the category selected based on the shielding configuration (Example of additional words
needed).
x
Accepted As Written
Withdrawn
Accepted As Modified
Rejected
Deferred Deferred to be wordsmithed
Other
Proposal Page Number:
2 of 3
SC-135/ED-14 Change Proposal Form Rev G
Rejection Reason / Comments:
Proposal Deferred To:
RTCA SC-135 Concurrence
Proposal Disposition By:
EUROCAE WG-14 Concurrence
Date:
Proposal Page Number:
3 of 3
SC-135/ED-14 Change Proposal Form Rev G