Northern Airborne Technology ACP53-001 - Manual (Page 25)

ACP53-001 DACS Audio Control Panel
SM75 Installation and Operation Manual
Section 3 Rev: 1.00 Issue 1 Page 3-4
ENG-FORM: 806-0113.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
3.4.6 Mode Control
Note: Confirm the specific criteria associated with this installation with your installing agency.
On defined ACPs, this switch is hard-wired into the audio management unit installed in the system.
Typically, these would be ACP 1 and ACP 2 (User 1 and User 2 respectively).
EMER
BK-UP
NORM
EMER
BK-UP
NORM ISO
3.4.6.1 NORM (Normal)
When normal operation is required, all defined ACP mode control switches must be in the down (NORM)
position.
3.4.6.2 BK-UP (Back-Up)
When any defined ACP mode control switch is in the centre (BK-UP) position, the communications
management unit switches over to the back-up power supply and the system is placed into back-up mode.
The defined ACPs maintain full functionality via back-up microphone and headphone amplifiers, but all
other ACPs and headset functions are disabled. Any appropriate installed external indicator(s) will
illuminate to warn the other users that back-up (or emergency) mode has been activated.
Note: Aural Warnings have no redundancy except for the power input.
3.4.6.3 EMER (Emergency)
Emergency mode can be selected if a defined ACP selects EMER on the mode control switch. However,
the external audio management unit will automatically select emergency mode if it loses physical
connection with any defined ACP.
In Emergency mode, defined ACPs maintain a reduced level of operation. All other ACPs in the system
will lose all functionality.
Typically, when a DACS AMU50-001 is in Emergency Mode, User 1 will be connected to COM1, NAV1,
Direct 1, Direct 2, Direct 3 and all alerts. User 2 will be connected to COM2, NAV2, Direct 1, Direct 2,
Direct 3 and all alerts. All audio will be at a fixed level selected at installation. CVR1 and CVR2 will
continue to provide outputs of headphones audio and hot mic audio from Users 1 and 2 respectively.
Keyed intercom audio is maintained between User 1 and User 2 at a fixed level selected at installation.
Any appropriate installed external indicator(s) will illuminate to warn users that emergency (or back-up)
mode has been activated.
The mode control is a red three-position locking toggle switch that can be used by
designated ACPs ONLY to select the operational mode - NORM (normal), BK-UP
(back-up) and EMER (emergency) - of the unit. The locking mechanism prevents
accidental de-selection of the currently selected mode.