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Speed Events are generated on the iFace and the IVUTelematics Box. Devices that do not generate speed events in line with NextGen include T-SPOT and any other device we do not write software for.
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There are different speed limits used based on what device capabilities are available:
- IVU Telematics Box – one global config limit
- iFace
- global config limit
- vehicle limit – based on what the vehicle type is set to on the iFace (eg if set to Road Train this will be 90km/h, B Double 100km/h, Car – no limit)
- signposted limit – if navigation is installed, the signposted limit of the road (please note that by default, signposted limits for speed events are disabled, due to inaccuracies of the road speed dataset. This can be re-enabled by the NextGen configuration of devices).
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An important note is that more than one device in a vehicle may be generating a speed event. Consider a vehicle setup in NextGen and both an IVU Telematics Box and iFace assigned to that vehicle. If both devices are enabled for speed events, they will both generate the data which will be used for alerts and reports. Note that the speed limits used on each device may differ at any time (eg config on IVU Telematics Box set to 100km/h, vehicle type on iFace set to Road Train which has limit of 90km/h). This possible difference, along with GPS quality and environment, means that it is not guaranteed that both devices will generate identical events.
Noting the above, it does mean two alerts may be raised for the one instance of speeding (one event from the IVU Telematics Box and one event from the iFace). Both events will also appear in the report.
We have implemented a feature in NextGen such that if an iFace is attached to a vehicle and an IVU a Telematics Box is also attached to the same vehicle, and both devices have the speed events agreement attached, then the iFace will automatically have speed events disabled. This is to ensure only one device generates the events, and the IVU Telematics Box takes precedence because of its higher level of accuracy. This option can be explicitly overridden via the configuration of devices in NextGen.
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