DISTANCE FAQS
HOW ACCURATE IS THE GPS TRIP METER?
Under good signal conditions, with 8 or more satellites visible, our customers report measuring an 8km stretch of measured road to within 4m. At this resolution, it is impossible to tell whether the error is due to the trip-meter, the customer not following the exact track on each measurement or the original measurement being slightly off. We would expect better than 1% under typical measurement conditions.
HOW ACCURATE IS THE POSITION ON THE GPS TRIP METERS?
Under good signal conditions, the horizontal position accuracy is 2.5m. The GPS Trip Meters have an indicator telling the operator how many satellites are being tracked so that one is aware of signal quality.
DOES THE GPS TRIP METER REQUIRE A CONNECTION TO THE VEHICLE?
No. All you need to do is to supply power through the lighter socket. Hummingbird Electronics uses a combination of spatial coordinates and Doppler frequencies provided by the GPS satellite constellation to calculate accurate distance.
WHAT DATUM DOES THE GPS TRIP METTER USE?
The standard datum used is WGS84 (World Geodetic System - 84). It is by far the most commonly used datum. Other datums are available if required. If you don't understand what the datum is, don't worry, most people don't; it won't affect the quality of your user experience at all.
DOES THE GPS TRIP METER TAKE HILLS INTO ACCOUNT WHEN MEASURING DISTANCE?
Yes, the GPS Trip Meter calculates 3-dimensional distance, taking hills into account to give you an accurate road distance.
CAN I PRE-LOAD THE GPS TRIP METER WITH A CHAINAGE VALUE?
Yes, distances can be pre-loaded by using the buttons on the front of the GPS Trip Meter or via the optional remote control.
HOW ARE THE ODOMETERS POWERED?
The HMOD1000 has a standard cigarette lighter plug, however if this does not suit it can always be removed and hard wired into a power supply between 9-32V.
CAN THE ODOMETERS BE USED ON TRAILERS WITHOUT A CONSTANT 12V FEED LIKE A CARAVAN WOULD?
The HMOD1000 does not need a constant power supply as the device saves all settings and odometer values to the device, however the unit may take a short period of time to acquire a solid GPS lock upon power up.