ERU50-001 Emergency Relay Unit
SM83 Installation and Operation Manual
Installation and Operation Manual
Issue 1.01
Page 2-2
CONFIDENTIAL AND PROPRIETARY TO COBHAM
2.4.1
Warnings
N/A
2.4.2
Cautions
N/A
2.4.3
Cabling and Wiring
All wire shall be selected in accordance with the original aircraft manufacturer's Maintenance Instructions
or AC43.13-1B Change 1, Paragraphs 11-76 through 11-78. Unshielded wire types shall qualify to
MIL-W-22759 as specified in AC43.13-1B Change 1, Paragraphs 11-85, 11-86, and listed in Table 11-11.
For shielded wire applications, use Tefzel MIL-C-27500 shielded wire with solder sleeves (for shield
terminations) to make the most compact and easily terminated interconnect. Follow the connector map in
Section 2.6 as required.
Allow 3" from the end of the shielded wiring to the shield termination to allow the connector hood to be
easily installed. Reference the interconnect drawing in Section 2.6 for shield termination details. Note that
the hood is a "clamshell" hood, and is installed after the wiring is complete.
Maintain wire segregation and route wiring in accordance with the original aircraft manufacturers
Maintenance Instructions.
Unless otherwise noted, all wiring shall be a minimum of 22 AWG. Refer to the Interconnect drawing for
additional specifications. Check that the ground connection is clean and well secured, and that it shares
no path with any electrically noisy aircraft accessories such as blowers, turn and bank instruments or
similar loads
.
2.4.4
Post-Installation Checks
2.4.4.1
Voltage/Resistance Checks
Do not attach the ERU50 until the following conditions are met.
Check the following:
a) Check P1001, pins <20> <21> and <34> for continuity to ground (less than 0.5
Ω
).
2.4.4.2
Power On Checks
Power up the aircraft’s systems and confirm normal operation of all functions with the ERU50-001
Emergency Relay Unit connected.
Upon satisfactory completion of all performance checks, make all required log book entries, electrical
load, weight and balance amendments and other documentation as required by your local regulatory
agency before releasing the aircraft for service.
