Anyone use GPS anchor alert?

[Fergus]

If so, does it use a lot of power? I have a Furuno unit..

Thanks

 

[bigmart]

No

Martin

 

[mainshiptom]

No it does not take much power just switch the lights off ! I also leave my depth sounder on and write down the time and depth, say every hour?

Tom

I also save the location for future use ! giving the waypoint a menigful name like "comfi anchor" but shorter.

 

[Phoenix of Hamble]

I also use it..... works just fine... v little power drain.... great, as Tom says, for finding deep spots again!

 

[snowleopard]

Whenever I anchor or even spend the night on someone else's mooring (I once dragged a mooring). I also leave the depth on with the shallow alarm set. Electronic gear uses very little current.

 

[Phoenix of Hamble]

Two weekends ago, the shallow alarm saved me from running aground when I dragged on the turn of the tide..... 'nuff said....

 

[A1Sailor]

Yes. I turn the screen brightness down as low as it will go, and it doesn't seem to use much power; but I don't have an ameter!

 

[ValleyForge]

Sorry, no, but I can recommend a night scope - even on a pitch black night you can pop your head up & check the surroundings (you know, when the rigging hums that bit louder, chain creaks a bit more that sort of thing). Wonderfully reasurring sometimes !

 

[cliff]

Anchor radius set on 0.1nm - few false alarms during the night. Set on 0.2nm no false alarms.

Depth sounder set for shallow alarm depending on where and when anchored / moored.

Power consumption negligible (compared to TV, Video, DVD, fridge, fridge freezer, beer cooler etc. /forums/images/graemlins/wink.gif /forums/images/graemlins/grin.gif)
----------

“Artificial intelligence is no match for natural stupidity”
Skype id:cliffillupo

 

[graham]

i recently left my boat for a week with echo and depth on . It hardly had any affect on the battery (single 85ah).

I wanted to use theGPS Anchor Alert facility recently but couldnt remember how to or find the instructions.Still seemed to sleep ok though.

 

[VicMallows]

Power is insignificant, and I usually leave anchor watch set.

But I do wonder what my Garmin 128 is actually measuring: what position does it monitor as the 'anchor position' ? I would prefer to be able to set a guard-zone OUTSIDE of a given position, but afaik this is not available.

Vic

 

[ShipsWoofy]

I set mine a couple of weeks ago on 0.1m and zoomed in the plotter to max.

The alarm went off, funny thinks I, I can see we have not moved.

I then watched the ships position shoot up north about 2 cables, then East then West and so on. Pushed the scale back to 0.2 and the alarm stopped.

I think the satellite clocks were having a bit of a barney.

 

[snowleopard]

The GPS128 measures movement from the point you were at when you switched the alarm on. I find .05 NM is usually OK in tidal waters, .03 in non-tidal. You will usually set the alarm once the anchor is dug in. After the turn of the tide you will be 2 x scope away from there.

If you want to set a guard zone, use the Arrival alarm setting - it will tell you when you get close to a waypoint.

 

[Guest]

Yes ....

Hit the button when you drop anchor - is the most accurate as you swing on that point.

If you are lazy and firget like me - hit it when you are settled - but allow a slightly larger radius .... than if you hit it at drop.

Excellent and well advised to use ......... allied with a depth alarm .... gives peace of mind.

 

[VicMallows]

That's how I would expect it to work. However, if you leave the alarm ON all the time, it still seems to work, so must reset/set itself after the boat has been static for a certain length of time. Thus, even though I havn't deliberately done anything, the anchor alarm will sound once I get under way again. It is the criteria for this 'auto-setting' functionality that puzzle me.

Vic

 

[Rob_Webb]

We live by them out here, power consumption shouldn't be an issue if your house batteries are bascially sound. Agree that experimenting with sensitivity is useful, praps 0.1 too tight, 0.2 more workable.

 

[Abigail]

We have one for the first time this season on our newly fitted Garmin 1289. We love it and it certainly helps to sleep.

We leave it on 0.2nm (01.nm too sensitive) and usually do it once anchor in and set. This means that it goes off when we swing but we like that as it gets us to check on the situation at that time. (I did spend ages working out how many meters in a nautical mile the first time ...)

It doesn't seem to have had any impact on power at all but we have over 500leisure amphours, three solar panels and a wind genny - at this time of year we wake up with more charge than we had when went to bed!

Here on E coast, leave the depth sounder on as well often.

 

[charles_reed]

Power consumption negligible.

I set mine as close as possible to 2(scope-water depth). This is usually about .02nm or 40 yards.

The old Garmin 5-channel reciever used to frequently set off false alarms (beacon error). the WAAS-augmented system scarcely ever lies.

 

[Ships_Cat]

I always use the GPS anchor watch except for brief stays. However, I seem to use a much tighter setting for the swing radius than what most others are saying yet we only rarely get false alerts. We also adjust the swing setting according to the depth anchored in rather than just use the same all the time as some are also saying.

Usually I just take the length of chain veered plus 40m to allow for the boat length (12, in our own boat's case) and GPS error, plus some according to how accurately I set the alarm over the anchor position. Pythagoras causes a bit extra over estimate. Then I divide it by 20 to get 0.01's of a nautical mile for the swing setting (I know there are 18.52 but 20 is easier to work with in simple cats' heads).

For example, drop anchor in 20m water (HW), 3x scope, so 60 m chain out. Add 40 gives 100m. Hit anchor watch pretty much over anchor position so nothing to allow for uncertainty so divide 100 by 20 gives 5 - that is the swing setting for the anchor watch in 0.01's nm so set it at 0.05 nm.

There is no extra work in doing the calculation as one should be doing so in any event, whether alarm set or not, to make sure one is clear of dangers when swinging.

Will set it even closer if dangers very close (and we will also back up to them against the anchor to check that we don't hit them in the night if swing on the scope).

John

 

[bob_tyler]

"The old Garmin 5-channel reciever used to frequently set off false alarms (beacon error). the WAAS-augmented system scarcely ever lies. "

Thought that WAAS (EGNOS) was not yet working in Europe!