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A smiling face = a happy DeviceNet network

01 February, 2001

A smiling face = a happy DeviceNet network

A Canadian company, Woodhead Connectivity, has developed a suite of tools that it claims could slash downtime in DeviceNet networks by more than 90%. The tools can be used by non-experts to find faults in minutes, that might otherwise take experienced engineers hours or even days to pinpoint, Woodhead asserts.

Woodhead`s NetAlert suite consists of three main tools:

• NetMeter, a handheld instrument that analyses the DeviceNet power supply and message stream to identify both device-specific and network-wide problems, and indicates the results by showing a smiling face for a healthy network, or a sad face for a sick one. It can also display measured values of key parameters.

• PowerMonitor, a computerised power analyser that samples the DeviceNet bus voltage and reports on its condition using coloured LEDs - blue for low voltage, red for high voltage, and yellow for transients or ripples on the power supply; and

• TrafficMonitor, a data analyser that uses LEDs to indicate key parameters such as error rates and bandwidth usage.

The NetMeter has an Autosearch mode which scans through more than 600 bus measurements to find any out-of-specification values. It then uses built-in intelligence to determine the importance of these measurements to the network.

Both the PowerMonitor and the TrafficMonitor hold the worst-case conditions and flash the corresponding LEDs for 24 hours. This allows the user to see both the present conditions and the worst recent conditions.

The tools, on which patents are pending, have been developed by combining technologies from three Woodhead companies: SST, Brad Harrison, and AI/FO. They also draw on ten years of DeviceNet troubleshooting by engineers at SST, which was the first company to approved by the Open DeviceNet Vendors Association (ODVA) to undertake conformance testing.