Light in GPS antenna flashing

Aug 1, 2011
3,972
Catalina 270 255 Wabamun. Welcome to the marina
http://c470.jerodisys.com/470Lib/gps_125.pdf

Did the previous owner leave you a boat book with all manuals for boat systems? How bout following the wire from the gps antennae to its power source....
The Ray GPS is a white wire, a "spur" in Rayspeak. It could plug into any white connector in the network. At some point in the network there is a splitter of some description, either a "t", with two blue (backbone) and one white; a junction box, with two blue and 3 white; an "itc5" which is an input spot for older instrument devices. If you're not confused enough yet, there's also a power feed to the brains of the AP if there is one, and some, but not all AP controllers will feed the network. (My SPX5 requires power but won't feed the network, while the SPX10 will) The gps transducer does not have more than one plug, so don't bother looking there. The bet would be that there's a splitter someplace within a meter of the AP controller, (again based on cable lengths) and since the controller requires power it would make sense to power the network from there too.
Bottom line here, there is a white plug someplace that has a red and black wire coming off it,
ST1_to_STNG_Converter_Kit[1].1.jpg like the cable on the left,
and given the cost of the backbone cables, that may or may not be within 20 feet of the electrical panel.
 
Nov 19, 2009
289
Hunter 45CC Ft Pierce and Abaco Bahamas
I do know that the generator was installed at the dealer in New York after the boat was bought. So as far as a wiring diagram, I haven’t seen one. I think I’ll just leave it be, I’m not sure it’s cauing me any issues anyway. Thanks for all the help, y’all are great.
 

Joe

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Jun 1, 2004
7,999
Catalina 27 Mission Bay, San Diego
You can't break it by turning off the power. The modern networks carry power for the smaller instruments and displays, whereas larger devices such as chartplotters and ap computers will require a separate power connection. The gps antenna is inserted into the network to provide data to whatever instruments request it... such as vhf radios with dsc, auto pilots, even chartplotters. If you remove the power from the gps antenna it's the same as turning off your hand held.... it just boots up again when you turn the power back on. In the manual I posted for example, the flashing green light acknowledges the gps had acquired satellites and was transmitting info to the network.
 
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Aug 1, 2011
3,972
Catalina 270 255 Wabamun. Welcome to the marina
I think I’ll just leave it be, I’m not sure it’s cauing me any issues anyway.
The power draw will not do any more damage than cause the batteries to trickle drain constantly, which will reduce their lifetime and depending on the draw and the time between real use could leave you in a state where there's not enough reserve to start the motor.
 
Oct 26, 2010
1,883
Hunter 40.5 Beaufort, SC
I do know that the generator was installed at the dealer in New York after the boat was bought. So as far as a wiring diagram, I haven’t seen one. I think I’ll just leave it be, I’m not sure it’s cauing me any issues anyway. Thanks for all the help, y’all are great.
It really won't be that hard to do a quick check to see which switch on the panel provides power to the gps and would be worth your while to find it. There is no use in taking a chance on draining your battery. Unless you are anchored and have to have an anchor light is there anything that you absolutely have to leave on when you are gone. Just turning off your main DC breaker should kill power to everything but the bilge pump if you don't want to go to the trouble of finding the switch. By the way, I think Mainesail and most people on this board would suggest that you learn what all the switches on your boat isolate so you can do "damage control" if you have to.
 
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Nov 19, 2009
289
Hunter 45CC Ft Pierce and Abaco Bahamas
Thanks for the input. I’m on a mooring in Hope Town Bahamas right now for the winter. I have 300 watts of solar panels that keep the batteries up nicely. If they get a little low after a cloudy day I start the Genset and top them off. When I do leave the boat for some time in the future, and hopefully have someone else on board, I can start switching the breakers off one at a time and see which one it is wired to.

Ron
 
Aug 1, 2011
3,972
Catalina 270 255 Wabamun. Welcome to the marina
To @smokey73 s point, and with all due respect to being a new owner, a 9v battery can deliver enough power to heat a wire to combustion. There is a very good reason for powering things off when you are not there, and even in the case of not using them. There's a statement made here quite often, "your boat, your choice".
 
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Nov 19, 2009
289
Hunter 45CC Ft Pierce and Abaco Bahamas
OK OK I made me a Capt’n and Coke and started by turning of a breaker, climbed the steps, light still blinking, back down the steps, turn that breaker on, turn a new one off, climbed the steps, light still blinking. Back down the steps .... 18 times. Eureka! It was powered by the auto pilot. Left it off. Time for another drink.
Thanks guys
 
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Aug 1, 2011
3,972
Catalina 270 255 Wabamun. Welcome to the marina
When you catch your breath, see if the plotter is on the same breaker. Then the whole mystery is solved.
 
Jun 1, 2009
1,737
Hunter 49 toronto
Ok,
On the DC breaker box, there is a push in breaker labeled Seatalk (or something like that) It is 5A.
It supplies power to a small 3-way ST junction box which is installed on top of the box behind the plastic facia panel.
This is not to be confused with instrument (or radar) power, which is on a separate higher current breaker.
The gps antenna gets it power from the seatalk bus. The ST60 instruments (or whatever you have), get their power from the toggle breakers.
What you should do is a minor modification and require the push-in 5A breaker to be powered from the instrument toggle breaker
 
Jun 1, 2009
1,737
Hunter 49 toronto
Just checked the schematics
It's on the autopilot breaker
That powers the ST junction.
So, it is on a toggle breaker after all.
 
Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
It can be a bit confusing for some people to understand how a backbone system works, but the following gives a basic description to help understand it when connecting new devices, or troubleshooting.... or to just to understand why they have a power draw when all components are off.

it doesnt matter if you have a small boat with one or 2 devices/components attached by a backbone system, or a large ship with many components in the system, the system is the system and it all works the same...

Im not sure about the generation of seatalk system you have specifically, but as close as it is to the nmea2000 (which now seems to be standard) I am reasonably certain that it operates nearly the same.

when installed on a backbone system, there are two power sources to every control head/unit. one source powers the screen and the units controls, and the other source comes from the network cable itself.

let me clarify a couple things here.
on a backbone system, its only the control head/units that need the extra power source..... everything the retrievers/senders require for proper operation, is offered thru the backbone.
most "basic" displays that have no controls that can be used to adjust the system settings, may operate as soon as connected to the backbone, as some displays use very little power and can draw what it needs thru the backbone cable..
and, any n2k compatible unit that is installed and is NOT connected into the backbone system, almost always can be used with only one power source to it.

the backbone network is designed to be powered on all the time, regardless whether any of the attached devices are on or off.
and this is why in the installation instructions it recommends an on/off switch be installed in the wire that powers up the network backbone, so that it can be shut off when the network will be unused for longer periods.
the network system still has the same power draw when all components are off, which can be a respectable amount, depending on the size of the backbone system. (some longer systems require a power source from each end to feed the system)

all " retrievers/senders" (gps antennas, transducers, engine senders, tank monitors, wind/weather instruments ect..) are still powered up and working even when the component itself is not.. (the screen is off but the internals are only in sleep mode and still alive from the system power)

the reason is, some types of boats have more than one station, and the electronics can be shut off at all stations not being used at the time, but all of those at the working station can be on and the network still powered up..... then, if one of the components at another station is desired to be monitored, it can be turned on and is immediately ready without waiting for it to initialize..
sometimes a boat may be anchored with all network devices off except for the wind/weather station, (or some other component) so the network still needs to be powered up.... but if the component is not connected into the system, it can be on while the network cable power is shut off.

as for turning it off when not needed, one should not use the circuit breaker as the on/off switch, but a dedicated switch should be wired into the system at the point where the network cable taps its power from.

a boat I purchased earlier this year (2017) had an extensive n2k network system that the PO did NOT understand how it was supposed to work, and so most of the electronics and tank monitors didnt work, even though he hired his "electronics guru" neighbor to install them, new, 3-4 years ago... nearly everything in the system is redundent ( 2 of everything) and is quality stuff, but that means nothing if it doesnt work.

I will admit that I didnt know a lot about the n2k system at the time, but as my brother bought a new boat about 4 months before I aquired this one, and he wanted his electronics connected in a system to his n2k ready motor... so I had some minor experience in building a small 2 component system on his boat.
but the system on the boat I bought was much bigger and already installed and, NOT working, so was a large headache..... until I realized there were 2 n2k backbones running thru it.... then it became a smaller headache while trying to sort one system and its components from the other.
I learned what the previous owner never did... you can connect ALL the components on to one backbone cable, AND the backbone cable needs its OWN power source.... with a shut off switch.
 
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Aug 1, 2011
3,972
Catalina 270 255 Wabamun. Welcome to the marina
Nice write up but technically incorrect on one point. I reality, most devices on the network do not need two power sources as stated. While that's true for power hogs, mfd and AP controllers, it's not the case for transducers and basic displays. (Although the mfgrs are clearly moving away from "basic" displays)
 
Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
Nice write up but technically incorrect on one point. I reality, most devices on the network do not need two power sources as stated. While that's true for power hogs, mfd and AP controllers, it's not the case for transducers and basic displays. (Although the mfgrs are clearly moving away from "basic" displays)
you are correct... its only the control head/units that need the extra power source.
everything the retrievers/senders need for proper operation, is offered thru the backbone.

I will edit the write up..