AIS connected to "hot battery bus" - why?

[dunedin]

........... The "navigation" switch kills the chart plotter etc and I wondered whether to move the AIS power across to that feed.

That's what I would do. And indeed thats what our boat builder did.
I don't want the AIS on in harbour. And I certainly don't want it draining the battery power when away from the boat.
Don't understand the suggestions of switching to stealth/silent mode- even more pointless to have it still on and using power when away from boat, but not transmitting.

 

[Refueler]

I can see point if the boat is anchored and you go ashore .... then on phone - you can see if boat moves ... but other than a location with risk of boat going walkabout .. there's no point .. It would have to be in full TX mode ... but as per example of Onwa : "In Port" selected in message part, also reduces the alarm part.

As to wiring a switch and having it behind a panel ???? I don't understand that ,,, surely bring switch out where it can be accessed ?

 

[wonkywinch]

As to wiring a switch and having it behind a panel ???? I don't understand that ,,, surely bring switch out where it can be accessed ?

Because I can't see a reason to ever switch the tx off other than if it sent incorrect info or I was testing something. Also I don't want to disfigure the front panel with superfluous switchgear. It's tucked away, accessible if I need it.

 

[Refueler]

Because I can't see a reason to ever switch the tx off other than if it sent incorrect info or I was testing something. Also I don't want to disfigure the front panel with superfluous switchgear. It's tucked away, accessible if I need it.

I have a pal with a boat who sends out AIS all time as you post ... I am not only person who asked him why ... He actually denied it was sending till I showed him my phone and the timestamp of his AIS ...
He never bothered to change it ... his choice - but I am fed up with AIS alarm when I fire up the Garmin MFD ... I have to go into AIS and switch off alarms ... then remember to re-enable after leaving berth.

 

[Sandy]

Interestingly, I am about to add a 'hot' circuit to the boat this winter for the Navtex and was thinking of moving the AIS onto that; using stealth mode when on the mooring.

With the advent of solar panels I'm quite happy to leave one or two things running.

 

[PaulRainbow]

ONWA actually along with other such as Matsutec - DO have IN Port mode ... as well as option to turn off TX ..

That's for the older B class and later B+ class models.

But I do agree ... switch off when unattended at mooring.

But there is no AIS navigation status "In Port". So if your AIS sends a status of "In Port", how does my AIS know what that means or how to deal with it ?

Have you set yours to "In Port" and looked at it from another AIS, or Marine Traffic etc to see what comes up ?

Perhaps it doesn't send "In Port" but actually sends "Moored" ?

 

[PaulRainbow]

Interestingly, I am about to add a 'hot' circuit to the boat this winter for the Navtex and was thinking of moving the AIS onto that; using stealth mode when on the mooring.

With the advent of solar panels I'm quite happy to leave one or two things running.

Sorry Sandy, that makes no sense. Why leave AIS on and receiving, but not transmitting ?

 

[Sandy]

Sorry Sandy, that makes no sense. Why leave AIS on and receiving, but not transmitting ?

Satellite requisition time.

It can take 20 mins to get a fix and I am usually well off the mooring in that time. As I pass through a busy military port, Plymouth, there is a lot of shipping and I like to be 'electronically' waving at everybody. Longroom (VTS) can also see me.

 

[PaulRainbow]

Satellite requisition time.

It can take 20 mins to get a fix and I am usually well off the mooring in that time. As I pass through a busy military port, Plymouth, there is a lot of shipping and I like to be 'electronically' waving at everybody. Longroom (VTS) can also see me.

Fair enough.

That's a long time to acquire satellites though Sandy, which AIS do you have ?

 

[Momac]

I understand what folks mean but really what inconvenience does it cause if boats in a marina have AIS switched on?
Its not like the screen clutter is a problem as you are hopefully not going to navigate in a marina using the electronic chart.

Folks wanting to use the AIS to remotely via internet see the boat hasn't moved seems like a good enough justification.

A little more tolerance of the preferences of others would be better than becoming agitated over a trivial matter. It snot like moaning about it on this forum is going to make any difference.

As for alarms I switched the AIS audible alarm off a short while after I first fitted AIS. This was due to all too frequent alarms even in the relatively quiet waters that I inhabit. Maybe some equipment doesn't allow the audible alarm to be permanently off ?

Personally I have my AIS powered via a switch and I have it switched off at present. In any case the current location of the boat the AIS signal is not picked up via the internet AIS sites.

 

[Sandy]

Fair enough.

That's a long time to acquire satellites though Sandy, which AIS do you have ?

It is, but there is a lot of metal around!

The unit is a VespaMarine AIS Watchmate.

 

[Refueler]

But there is no AIS navigation status "In Port". So if your AIS sends a status of "In Port", how does my AIS know what that means or how to deal with it ?

Have you set yours to "In Port" and looked at it from another AIS, or Marine Traffic etc to see what comes up ?

Perhaps it doesn't send "In Port" but actually sends "Moored" ?

My problem is that I work in an industry that uses Class A and reads Class A, B / B+ .... it is Nav Officers responsibility to change the status tx'd ... and the recv'g units display Rcvd status ... TBH - I cannot remember exact wording ... but it does change dependent on others Tx status set.

As to Yottie gear ... I will have to leave that question till winters end .. its too cold out there to go just to check this ... but I do know that Yottie gear does not have as much detail transfer as commercial A ... so most likely needs a commercial unit to read it.

OK ... just pulled out the manual and it says that IN PORT setting in Menu - stops unit alarm entering port ... on departure OUT PORT enables units alarm feature.
So in fact the TX status appears unchanged .. its the on-board alarm that is ..

Later I will be interested to pull up anothers info rec'd from my AIS when weather is suitable !!

 

[dunedin]

Satellite requisition time.

It can take 20 mins to get a fix and I am usually well off the mooring in that time. As I pass through a busy military port, Plymouth, there is a lot of shipping and I like to be 'electronically' waving at everybody. Longroom (VTS) can also see me.

About time you fixed your GPS aerial then. Most get a fix within 30 seconds or so on a restart. Or simply switch on your instruments 20 minutes ahead of departure. Few can get a yacht prepared from leaving car to being at sea in less than 20 mins.

 

[PaulRainbow]

My problem is that I work in an industry that uses Class A and reads Class A, B / B+ .... it is Nav Officers responsibility to change the status tx'd ... and the recv'g units display Rcvd status ... TBH - I cannot remember exact wording ... but it does change dependent on others Tx status set.

As to Yottie gear ... I will have to leave that question till winters end .. its too cold out there to go just to check this ... but I do know that Yottie gear does not have as much detail transfer as commercial A ... so most likely needs a commercial unit to read it.

OK ... just pulled out the manual and it says that IN PORT setting in Menu - stops unit alarm entering port ... on departure OUT PORT enables units alarm feature.
So in fact the TX status appears unchanged .. its the on-board alarm that is ..

Later I will be interested to pull up anothers info rec'd from my AIS when weather is suitable !!

The "In Port" setting makes sense now.

I've not seen an AIS where you can change the nav status, or all the other stuff you can set/change with class A, presumably to keep bandwidth to a minimum.

 

[Sandy]

About time you fixed your GPS aerial then. Most get a fix within 30 seconds or so on a restart. Or simply switch on your instruments 20 minutes ahead of departure. Few can get a yacht prepared from leaving car to being at sea in less than 20 mins.

You are making an assumption there, that I am using external GPS antennas. Actually, I am not a fan of them as they get in the way and fail from time to time. From cold both the AIS and VHF take time to build their tables of where the satellites are to get a good fix.

Why does it take people so long? Here is the drill when from I get to the boat:

Climb on board, tie the dinghy up, turn the gas on, remove instrument covers, open the hatch, switch everything on (electrics and engine), pop back up on deck, check that water is coming out of the exhaust, check the rudder moves, check forward and reverse propulsion, walk up the starboard side checking the rigging as I go, drop the mooring, return to the cockpit down the port side checking the rigging as I go then slowly motor off the mooring. If I have crew it is even faster and we have the luxury of tea/coffee and sticky buns as we run down river.

From time to time we come alongside the club pontoon to resupply the boat - restock the drinks cabinet, water tanks and transfer some fuel in gerry cans.

We all do things in different ways.

 

[Refueler]

The "In Port" setting makes sense now.

I've not seen an AIS where you can change the nav status, or all the other stuff you can set/change with class A, presumably to keep bandwidth to a minimum.

Ships settings cover moored, anchored, underway, making way and eta. The Nav Officer changes the setting based on ships situation at the time. Ship usually has not only the CAS showing the plot ... but a text only repeater that all the AIS targets are listed ... you can scroll through and choose one ... it will then display status and other info. Later CAS of course combines the two ...

Just for interest .. when I used to supervise Ship to Ship cargo transfers ... I used AIS to know where the other ship was when calling them up to rendezvous. Quite often the info I was given by them via VHF was not in agreement with AIS info / plot !!

 

[oldgit]

And F to the rest of us!

Do explain how a single AIS transmission 15 miles inshore up a river causes a problem or how half dozen AIS signals in a marina presents a danger to other boaters. ?
The skipper lives 60 miles away from his mooring.

 

[MontyMariner]

Because I can't see a reason to ever switch the tx off other than if it sent incorrect info or I was testing something

I turn my Tx off when I'm floating around in the Solent, except if it's foggy, there's more than enough AIS clutter up around there without me adding to it!

 

[Refueler]

I turn my Tx off when I'm floating around in the Solent, except if it's foggy, there's more than enough AIS clutter up around there without me adding to it!

OK ... if in terms of AQIS alarms - I agree ... but AIS does not 'fill' the airwaves in same way as entertainment stations, CB or normal VHF over-riding or conflicting with other tx's on same freq. AIS uses 'slots' ....

 

[MontyMariner]

OK ... if in terms of AQIS alarms

I was thinking more about the clutter on the CP screen.