ELD-1 Hardware

Vocia End of Line Devices (ELD-1) are designed to be used in conjunction with Vocia amplifiers and output devices to confirm the integrity of a speaker line. This section is provided to aid in the use of the ELD-1. Please see the ELD-1 Manual for further information on installation of the device. Refer to the ELD-1 Wiring Topologies section for important details on installation and wiring.

Network Connection

In contrast to most other devices in the Vocia product range, the ELD-1 does not require setting a Device ID. Please connect the device to a PoE-compliant network and at the end of the speaker line. ELD-1 devices are associated to their host output device and channel in the software.

The Ethernet connection carries control data as well as Power over Ethernet (PoE). PoE-enabled network switches or PoE midspan adapters must be used to power the ELD-1. These must be 802.3af compliant. The maximum distance between any unit and an Ethernet switch is 328 feet (100 meters) when using copper cabling. Additional Ethernet switches and/or fiber-optic cable can be used to further extend distances between units on a network.

If other network traffic shares an Ethernet switch with the Vocia network, a managed switch should be used with separate VLANs.

Speaker Line Connector

A plug-in barrier-strip connector on the ELD-1 connects the device to the end of the speaker line. The device needs to be connected to an appropriate monitoring point on the speaker cable. Typically this is after the last speaker on the line. The speaker line should be physically connected between the Com pin and the appropriate Low or High pin as defined in the table below.

For circuits connected to the Low terminal, the ELD-1 presents a 0.5 Watt loading to a 70V circuit and a 1 Watt loading to a 100V circuit.

Output Fault Detection

The Amplifier monitors faults on speaker connections using a combination multiple out-of-band (inaudible) high frequency tones for end-of-line detection. For end-of-line detection, one or more (up to 15 maximum) ELD-1 units must be connected to the end/s of the speaker line. End-of-line and ground fault detection may be individually enabled/disabled in 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 level should be adjusted to minimize clipping as severely clipped signals may also affect the 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
• Speaker cables longer than 500 feet (150 meters) may prevent correct operation of ELD and Ground Fault monitoring capabilities. The speaker line state may report incorrectly if longer distances than this is being used
• 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 to the requirements herein;
• Any external 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 the nominal output level (-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
• For EN54-16 compliance, one or more ELD units must be fitted. End of Line detection must be enabled in the Vocia software.

Fault Indication

When a fault is detected on the speaker line or amplifier channel, the lower left LED on the RJ-45 socket will illuminate Amber and remain on until the fault is resolved. Providing a valid PoE power source and Ethernet connectivity is available the ELD-1 the solid amber indicator can be used to physically identify the ELD-1 that is reporting an issue.

If there is a fault with an ELD-1 the ELD-1 Assignment tab in the Amplifiers properties can be used to identify which ELD-1 is reporting the fault condition.