The Quartix unit records all data via GPS in Latitude, Longitude grid co-ordinates which are then converted to UK Grid X, Grid Y Co-ordinates and finally into Post Code and Street Name. The location data is accurate to within 10 meters, although typically within 7 meters. Occasionally a neighbouring post code and street name may be selected where post code boundaries have changed and our quarterly update has not been applied. The reports supplied previously had a standard ‘New Trip Threshold’ of 250 meters, so any trips recorded under this length would not be displayed on the reports. For all new installs completed since the start of 2018 this threshold is now set at 10 meters.

The GPS antenna manufacturers quote an accuracy of 0.1 meters per second under ideal conditions, however signal quality will affect this figure slightly and we would therefore allow between a 5% and 7% variance in the speed recorded by the unit to that of the vehicle odometer. The Quartix unit is not affected by outside variables such as tire pressures, load weight, weather conditions, etc.

 The time is obtained from the GPS module which is locked to global time-standards, so is accurate to a fraction of a second. If the unit is in an area of poor GPS reception (e.g. an underground car-park) the unit keeps track of time using an internal clock which is less accurate (around 2% drift) but this is corrected as soon as GPS lock is obtained.

If the unit powers up in an area without GPS reception, there is provision for it to send time-stamps showing the elapsed time since ignition-on (rather than clock time) and when GPS lock is obtained, these relative timestamps are converted back to absolute times.

Every event is marked with a time-stamp, as described above; if the event cannot be transmitted immediately, it is stored complete with the time-stamp, which is included in any re-transmission. So the timestamp always reflects the actual time an event occurred, not the time the message was received by our servers.

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