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Page 3–5
18 September 2007
SYSTEM DESCRIPTION, INSTALLATION, AND MAINTENANCE MANUAL
eNfusion™ HSD-128 High-speed Data Terminal
5.
Cabling and Connector Requirements
This section provides general electrical installation information on power, ground, shielding 
requirements, and cabling that applies to all installation modes for HSD and HSD-X 
transceivers. 
A. Power Requirements
The aircraft power supply provides power to the HSD transceiver. This power supply must 
be +28 V dc nominal for models PN 1110-A-0001, 1110-A-0160, and 1110-A-0080. For 
HSD models, PN 1110-A-0060, 1110-A-0150, and PN 1110-A-0070, and HSD-X model 
PN 1110-A-0401, the power supply must be at 115 V ac, 400 Hz (nominal). 
The breaker rating for the HSD assembly is based on power consumption details provided 
in Table 1 Variants of Outline and Installation Diagram (1110-E-0001) presented in 225. 
The power requirements for the HSD-X transceiver are listed in the notes on the HSD-X 
Outline and Installation Diagram.
B. Ground Requirements
Improper grounding can potentially lead to ground loops and induced Electromagnetic 
Interference (EMI) or Radio Frequency Interference (RFI). When installing an HSD or 
HSD-X transceiver, follow standard grounding practices for both chassis and cabling 
shields.
C. Cable Shielding and Termination 
The preferred method of cable shield termination is in accordance with NEMA WC 
27500:2000 and ARINC 741. ARINC Report 413A – Guidance for Aircraft Electrical Power 
Utilization and Transient Protection provides more detailed information in Attachment 3-2, 
Wire Shielding and Grounding Requirements and in Appendix 7.
Unless otherwise stated, all cable shields must be connected to the closest aircraft ground 
at both ends of the cable as well as on both sides on any production break in the cable. 
Where applicable, terminate shields with connectors via the backshell or via a pigtail with 
a suitable termination to the closest aircraft ground. 
General aviation cable-routing guidelines apply. Refer to Table 3–1 for detailed 
information.
Note:
Typically, Ethernet and ISDN cable has multiple shields; terminate each shield 
separately. 
 Table 3–1. Cable Shielding and Termination Specifications
Cable 
Function
Conductor Type (Typical)
Single 
Point
Multiple 
Point
Minimum 
Conductor 
Coverage by 
Shield
Power Lines
Single conductor, stranded N/A
N/A
N/A
Digital Control
Twisted pair, stranded
Yes
85%
Serial Data
Twisted pair, stranded
Yes
85%
Ethernet Data
Twisted pair, stranded
Yes
85%