What is Chartplotter?
A chartplotter is a GPS navigation display that shows your boat's position on electronic charts in real-time.
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What it is
A chartplotter is a GPS navigation display that shows your boat's position on electronic charts in real-time. Modern chartplotters are touchscreen displays that can combine GPS positioning, digital chart databases, radar, sonar/fishfinder, AIS, weather data and autopilot control into a single display mounted at the helm.
What it does
The chartplotter continuously receives GPS satellite signals to calculate your position, then displays it as an icon on the electronic chart. It tracks your course, speed, and heading while allowing you to plan routes, set waypoints, view depth contours and identify navigation hazards. AIS integration shows nearby vessel traffic that can be essential for preventing collisions. Advanced units integrate radar for collision avoidance and sonar for depth and/or fishfinding. You can mark favorite anchorages, create complex routes, set safety alarms for anchoring and review historical tracks.
Why it matters
A chartplotter is your primary navigation tool for safe piloting, especially in fog, darkness or unfamiliar waters. It can help to prevent groundings by showing real-time depth and your position relative to hazards. MOB (Man Overboard) functions can save lives by instantly marking rescue coordinates. However, overreliance is dangerous. Chartplotters can fail from power loss, water intrusion or antenna damage. A failed chartplotter in poor visibility can put you in immediate danger if you haven't maintained backup navigation skills.
General Maintenance
Update charts at least once a year or before extended cruising (aids to navigation, depth surveys, and hazards change regularly), and ensure that all functions including MOB, waypoint creation and alarms are functioning. Keep the screen clean with microfiber cloth and fresh water. Avoid using harsh cleaners or paper towels that can scratch the display. Corrosion can damage cable connections, so regularly check seals and fittings to ensure the system remains watertight. Before purchasing a new chartplotter, ask the manufacturer about the recommended maintenance schedule for your specific climate, and store the product’s serial number somewhere easy to access. Having it on hand will help customer support quickly locate your unit if any issues arise. Most importantly, maintain paper chart and navigation skills as backup. Never trust electronics alone.
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