Maretron DSM250-01 user manual Trigger Type is GPS Quality Alert

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The Outside Radius Alert and the Anchor Alert are very similar. The Anchor Alert is designed to allow the input of relatively small radius values, and may be displayed graphically through the Anchor Watch Display (section 7.1). The radius of the Outside Radius Alert is specified in either Nautical Miles or Kilometers, while the radius of the Anchor Alert is specified in Feet or Meters.

See Section 8.3.7.7 for details of the configuration of the Anchor Alert.

8.3.7.10Trigger Type is GPS Quality Alert

The accuracy, or quality, of a position fix provided by a GPS is dependent on the number of satellites used to compute the position. A position based on less than three satellites is considered a “1D” lock, three satellites is a “2D” lock, more than three satellites is a “3D” lock, and more than three satellites with SBAS is a “3D-DGPS” lock. These different locks are indicative of the quality or accuracy of the given position with 1D having the lowest quality and 3D-DGPS providing the highest quality. The GPS Quality Alert is used to alert you if the quality of the position falls below a specified quality level.

8.3.7.10.1Trigger Configuration – GPS Quality Alert

Figure 267 – Trigger Configuration – GPS Quality Alert

Re-trigger Period – When you accept an alert, it will change to the “Accepted” state, and annunciators that are sounding for that alert will stop sounding. If the condition which caused the alert remains true after the amount of time in this field, the alert will return to the “Active” state, and annunciators will begin sounding again for that alert. If a value of 0:00 is entered, then the alert will never re-trigger.

Alert Set Point – The Alert will be triggered when the qaulity of the GPS fix, as reported by the GPS drops lower than the value specified in this field.

Possible Values are:

•3D-DGPS (best quality)

•3D-GPS

•2D-GPS

•1D-GPS

•No fix

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