BEL DIGITAL AUDIO
BM-A1-S
Operation
2004 BEL (Digital Audio) Ltd
4
Version 0.3
Alarm arming
No alarms are generated unless alarm functions have been ‘armed’.
The front panel alarm toggle switch has four functions:
1. Left hand position held – ALARM RESET - any armed input alarms are cleared
2. Left hand position momentary – resets bargraph peak-level indicators
3. Middle position – OFF/MUTE - the internal audible alarm is muted
4. Right hand position – SET - alarm functions are selectively armed
The switch must be held in the left hand ALARM RESET position for more than 3 seconds for
a reset to occur.
In the right hand SET position the inputs currently active are automatically detected and the
appropriate alarms are selectively enabled. The unit is then set to monitor only the active
inputs. The SET function can be disabled using a serial command.
If alarms are present, moving the toggle switch to the center position will stop the audible
alarm, but retain the visual alarm indications and TTL/serial alarm outputs. The switch must
be held in the ALARM RESET position for more than 3 seconds for all alarms to be cleared.
The center position is the recommended position when alarm indication is not required.
Note:
Restoring input signals to normal condition does not clear alarms.
Arming phase alarms
Only the phase LED on the front panel is armed using the SET switch. The audio tone and
external phase alarms can only be armed using serial control.
To prevent the anti-phase detector from generating intermittent alarms, only persistent anti-
phase conditions are used to raise an external alarm or generate an audio tone.
An alarm is generated when an anti-phase condition exists for more than 10 seconds.
