Biamp Vocia VO-4e, Operation Manual

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VO-4e
Amp Fault Inputs
Four amplifier Fault Inputs are provided via a six-
way 0.2” (5.08mm) pluggable screw terminal block.
These allow for fault monitoring of the output of the VO-4e as indicated from an external amplifier. By
default each input allows an external voltage-free contact closure to ground to indicate a fault condition
for the corresponding VO-4e Output channel. Inputs are pulled high internally to create a default non-
asserted condition. When configured for device failover the Amp Fault Input connections must be
paralleled between the main and failover device. This is software configurable so if inverse operation is
required this can be adjusted per input.
Output Fault Detection (VO-4e output channel used in conjunction with a Vocia End of Line Device
1 [ELD-1])
The VO-4e monitors audio output circuit integrity per channel by monitoring multiple out-of-band
(inaudible), high frequency tones in conjunction with ELD-1 devices that have been assigned to the
relevant channel using the Vocia software. To prevent the possibility of interference with these monitored
tones:

Recorded audio messages or audio content with continuous or swept tonal components (e.g., alert
tones) should be band limited at 15 kHz during recording;

Program signal levels should be adjusted to minimize clipping, as severely clipped signals may also
affect these out-of-band fault detection tones.

The use of shielded speaker cable is not supported;

Highly capacitive speaker lines or loads may prevent correct operation of the ELD detection system;

Legacy monitored speaker circuits that use capacitors and resistors or similar methods must have all
legacy monitoring circuitry removed for correct operation of the ELD detection system;

If legacy speaker systems and speaker wiring are to be re-used, these must conform with the
requirements herein;

Any external power amplifier equipment must be capable of relaying the out-of-band fault detection
tones to the ELD-1. For reliable performance a frequency response of better than -3dB at 24kHz must
be supported through the amplifier and all speaker wiring up to the End of Speaker Line connections
on the ELD-1s;

The amplifier gain or level control must be set so that nominal output level from the VO-4e (-10dBu,
0dBu or +4dBu; as set in Vocia software) delivers an output level from the amplifier 6dB below the
amplifier maximum output level (clip level). This setting must be accurate and must remain constant for
predictable operation of ELD-1 units.
Failover Modes
Device-to-Device or Channel-to-Channel failover modes are supported. Only one type of failover mode
can be implemented per device.
Device-to-Device Failover
VO-4e units provide for Device-to-Device failover when a fault is detected. A Failover Link Cable must be
connected between the primary and the redundant units as shown. Connect ground to ground, and Pin 1
of the primary device to Pin 2 of the redundant device; connect Pin 2 of the primary device to Pin 1 of the
redundant device.