Wrongly located speed warnings

Seanscot · Posted: Wed Mar 18, 2009 11:41 pm Post subject: Wrongly located speed warnings

I was travelling from Largs to Fairlie (Scotland) today and discovered that I was getting a 30mph warning long before I had reached the limit signs as you enter Fairlie. Is this a feature of the speed camera database or something to do with POI info? In either case how is it corrected?
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Garmin Nüvi 760

PaulB2005 · Posted: Wed Mar 18, 2009 11:57 pm Post subject:

It depends on exactly where the messages occurred and what they said.

If it was something like

"30 Mph Speed Limit Ahead"

then it can be a warning built into the Nuvi map data.

Could you also still have the Garmin Cyclops database installed and active?

All alerts from the PGPSW database will have a format such as

GATSO: 12345@50

or

MOBILE: 223@40

so you can identify the camera from the database.

Unless you can be more specific about the message it'll be difficult to give a more specific answer...

PaulB2005 · Posted: Thu Mar 19, 2009 12:03 am Post subject:

I notice from our database there are 2 mobile camera locations on the A78 between Largs and Fairlie. Could these be the alerts you are referring to?

Andy_P · Posted: Thu Mar 19, 2009 12:06 am Post subject:

you say you were getting "a 30mph warning long before I had reached the limit signs".. If so, then it can't be the PGPSW database, as that only alerts to camera positions (fixed or mobile) NOT speed limits themselves.

PaulB2005 · Posted: Thu Mar 19, 2009 12:14 am Post subject:

POILoader assigns quite a long alert distance to Mobile locations by default so it is possible to be alerted to a camera whilst in one speed limit for a camera operating in a lower limit. A local dual carridgway here is 60 mph for a short section but 40 mph the rest, you often get Mobile alerts @40 whilst still in the 60 mph section.

POILoader help says the calculation is

PaulB2005 · Posted: Thu Mar 19, 2009 12:25 am Post subject:

Just run a simulation and whilst in a 60 mph section of road you do get alerts to MOBILE:25917@30.

However the speed limit then drops to 30 before you actually reach the mobile location, so it looks like the approach alert overlaps into a 60 mph zone.

Not much you can do about this other than consider using Ash10s Camera Manager to reduce the alert distance, but it might still happen somewhere else....

MaFt · Posted: Thu Mar 19, 2009 10:04 am Post subject:

paul - the default poi warnings on garmin are '30mph alert ahead' etc. it's only when you use camera manager or gpx convertor that you get the poi name itself!

Seanscot - it could just be that the camera is just inside the 30zone and therefore warns you of the camera speed (correct at 30) before the 30 zone starts...

MaFt

PaulB2005 · Posted: Thu Mar 19, 2009 10:08 am Post subject:

Seanscot · Posted: Fri Mar 20, 2009 2:33 pm Post subject:

Sorry to take so long to get back. The screen warning says

"xx mph Speed alert ahead"

As far as I know (but I'll check this later) I removed all the Garmin cyclops db material from my Nuvi 760 after I installed the Pocket Gps DB. Maybe I missed something.

The issue at the location mentioned was that the warning was already in Red and pinging back at me because I was travelling in excess of the approaching limit (30mph) signs at the beginning of Fairlie. The warning seemed to start about half-way between the exit and entry gates for Kelburn Country Park a good quarter to third mile from the limit signs.

I'm trying to get a sense of how these things work on the Nuvi!
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Garmin Nüvi 760

M8TJT · Posted: Fri Mar 20, 2009 3:50 pm Post subject:

Just a small point from a lurker who probably can't help because I don't know much about Nuvies, but are we talking about Speed Limit warnings or Speed Camera warnings. I get the impression that it's Speed Limit warnings the OP is talking about due to his references to 30mph limit signs, although there are also references to speed cam databases in his posts. Surely if it's speed limits, then that is a map problem, not a POI or speed cam problem.

eyeQue · Lifetime Member Joined: Aug 27, 2008 Posts: 235

It would appear that you are talking about 30-M-25917.
Garmin units using POI Loader [with default setting] have the initial proximity warning set to 0.30miles.

Then you will get repeat or overspeed warnings.

I have indicated the .3 proximity area as a waypoint - does that fit into your named entrances?

The proximity default for 60mph is 0.6miles.

Garmin POI loader with default settings produce the speed zoned icon and audible warnings with three types of alert.

Proximity

overspeed

reminders

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Garmin Oregon 300 + Garmin iQue 3600
My Zoned Speed Camera Icons, available here.

Seanscot · Posted: Fri Mar 20, 2009 5:09 pm Post subject:

EyeQue - I think you're spot on with the location and the point at which the warning occurs!

Where do you alter the default settings of the POILoader (on the Mac) as I don't see any Preferences settings?
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Garmin Nüvi 760

eyeQue · Lifetime Member Joined: Aug 27, 2008 Posts: 235

There is a choice with the POI loader to change settings and I have failed to get to work!

There is a method using Ash's program [which does work] this is on the website somewhere.

I now never change the default settings of the 'zoned' database as it is far safer to get the initial proximity as set, and the repeat alerts as set, it gives more time to slow from 60 to 30 for 'the young at heart' or 'old in mind' Razz

_________________
Garmin Oregon 300 + Garmin iQue 3600
My Zoned Speed Camera Icons, available here.

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