digitil gauge reading double speed

[vaughan]

have just put new df150 on my boat,water tested it and speedo is reading double actual speed.its all hooked via nmea 2000 to lorance hds7 elite.boat shop says leave it till first service but if its easy fix then will get it sorted now,thanks for any help

[Moonlighter]

Is it set to kilometres instead of nautical miles? If so from memory it can be changed in settings/units.

[vaughan]

yes set on kilometers but that should not affect it showing double the speed to my gps.it has the setting for kilometers so should read the right speed

[Moonlighter]

The gauge simply gets raw speed data from the HDS. However it has its own internal set of measurement units so even though the HDS might be set in miles, if the gauge units are set to kilometers, it will show speed in km, which are very close to double the nautical miles figure.

Just go into the gauge menu, settings, units, and use the dropdowns to set your preferred units for speed distance etc.

Also make sure that the data source for speed is set to ground speed or SOG.

If this is not the issue you are having, you will need to explain much more clearly exactly what is happening. We arent there to see what is going on so you need to spell it out in detail please.

[vaughan]

gps is set to SOG and set to kilometers in settings.the problem is at digital engine gauge reading wrong speed,so do i have to change engine gauge settings to match gps.is that what you mean above in comment,thanks for help

[Moonlighter]

Yes. Change the units of measure settings in the gauge.

[lesval]

I have a nearly identical issue.
Setup:
Df200
Lowrance Elite 7 HDI
Suzuki multi-function Gauge
NMEA 2000 between gauge and gps unit.
NMEA 2000 is correctly configured with power, backbone and terminators.

Issue is that the Guage reads 2.2 times the actual speed on the GPS. This does wonders to for mpg readings, but I'm wanting real data, not bragging rights. Any idea what might be causing this?
I have checked with both units set to miles, nautical miles, and kilometers respectively. There is no change in the error factor of 2.2X.