The ECM is inserted between the amplifier and loudspeaker circuit and uses a combination of voltage comparison and current monitoring techniques. The system can be configured for use with

low impedance and 100V line systems.
2 wire current monitoring of low impedance circuits.
3 and 4 wire voltage comparison monitoring of 100V line circuits.
Mains and DC operation.
Twin fibre network as standard.
Four auxiliary inputs.
Common fault output.
Integrated PC configuration utility.

Front panel controls are provided to facilitate the calibration of the unit in association with the panel LED’s. When in operational mode the LED’s show the current status of the individual loudspeaker circuits.

Monitoring Method

The system is suitable for use on 100V line systems from 30w to 1Kw and Low Impedance systems ranging in power from 60w to 1Kw into 4 or 8 ohms. Calibration is simple with the unit auto ranging to select the correct settings. The acceptance window for fault reporting is also automatically set with an option for the user to expand or contract this using the Windows based software available.
 
The system is configured to detect the presence of a low level 20KHz signal when no audio program is present. This signal is used to perform a high accuracy test of the load and line. Once an active signal is detected the monitoring continues but with an increased ‘window’ of acceptance to cater for variations caused by the program material. When the program material stops ( even for a couple of seconds ) the system reverts to the 20KHz tests.

System Interconnections

Eight separate inputs for connection to the amplifiers output are provided with the amplifier connected to terminals 1+ and 1-.

Eight separate outputs are provided for connection to the loudspeaker circuits. When impedance monitoring for low impedance circuits 1+ and 1- only are used. For small 100V line circuits ( up to 8 loudspeakers ) 1+ and 1- are used as the signal send and 2+ used for a third wire ‘End of Line’ return. For larger 100V line circuits or where complete rings are used the ‘End of Line’ return is connected to 2+ and 2- .

Four opto-isolated inputs for connection to external sources. Typically used to monitor DSP processor or UPS status.

A change over relay provides a common fault output that can be configured to provide a change in status for any fault occurrence.

Twin ( Primary & Secondary ) ST fibre connectors for the fibre connections to other elements ofthe system. The system is software configurable for single or dual fibre operation.