Failover is a function that can be configured on Vocia Amplifiers and VO-4e Vocia output devices. It is the ability to provide channel or device redundancy in the case that a primary device or output channel has a fault.
There are three modes of Failover operation: Channel-to-Channel, Multi Channel-to-1 (3-1 / 7-1 -Amplifier dependent) and Device-to-Device.
The following output devices support the following failover modes:
| Device | Channel Failover Modes | Device-to-Device |
| VO-4 | None | No |
| VO-4e | 1:1 | Yes |
| VA-2060(e) | 1:1 | Yes |
| VA-4030(e) | 1:1(x2), 3:1 | Yes |
| VA-4300CV | 1:1(x2), 3:1 | Yes |
| VA-8150CV | 1:1(x4), 3:1(x2), 7:1 | Yes |
| VA-8600(c) | 1:1(x4) | Yes |
| VA-8600(c) with VFOM-1 | 1:1(x4), 3:1(x2), 7:1 | Yes |
Standalone - No Failover configured. All amplifier models support this mode of operation.
Channel Failover (1:1) - One or more channel pairs can be setup to failover in case of a fault. You can only have failover between output channels 1-2, 3-4, 5-6 and 7-8. The number of channels available is dependant on the output device. Failover is one way and will require a power cycle of the device to return to normal operation (i.e. a fault in output 1 will fail over to output 2. Subsequent faults in output 2 will not failover back to output 1 regardless of whether the fault in output 1 is fixed or removed).
Multi Channel Failover (3:1 and 7:1) - If any of the primary channels experience an Alarm or if any of the Fault Inputs are asserted on the VO-4e the system will automatically transfer control to the Secondary Channel, which will continue to process and distribute audio, taking on all of the functions of the Primary Channel. If any subsequent secondary channels experience a fault after failover has occurred on the primary channel there will not be sufficient resources to support failover again until the fault condition is removed and a powercycle of the device is performed.
Device-to-Device Failover - A secondary device of the same model can be configured to provide device failover functionality. If a fault occurs in Device Failover mode, the entire output device will fail over to the secondary output device. Failover is one way.
Resetting a Failover requires power cycling of both devices. In the case of Device Failover, the Primary device should have power applied within 10 seconds of power being applied to the Secondary device to ensure that the Primary will take priority from the Secondary.
When the Vocia software is Online an additional Test tab will be visible when Device or Card Failover has been implemented. This allows Failover to be tested during commissioning, testing and training without the need to cause an actual fault in an amplifier channel or chassis.
Device Failover requires the use of a Failover Detection cable. If this cable is not present or is severed/shorted both devices may become active. See the relevant devices hardware section for wiring details.
Device Failover will also present a slightly different view of the output device dialog. Level Control and Alarms & Logs tabs will be available for the Failover Device in addition to the existing tabs for the Primary Device. Also, depending on the output device, new failover tabs may appear allowing further control of behavior when in failover mode.
If an end of line device such as the PLD-1 is being used on a failover channel, the channel being failed over to must also have that same type of end of line device attached.