6 Point Monitor Issue

[JLR]

I recently had my 6 point monitor rebuilt by Flights Systems for an issue unrelated to what is discussed below. In the course of the rebuild, Flight Systems replaced all four relays. My problem existed before the rebuild and remains after the rebuild. It is minor but annoying. In a nutshell, I am getting feedback or some sort of weak alarm through my piezo speaker on the monitor on start up. It goes away after five or ten minutes at idle and does not return until the motors are started again when cold. The test light shows all lights working properly. None of the lights comes on when this feedback alarm sounds nor do any of my bridge gauges show any signs for concern. Although this is not a real alarm, I would like to get it fixed. Any help would be appreciated.

 

[MikeP]

Along with what has been mentioned, check the voltage to the alarm system. Low voltage can sometimes trigger an alarm such as you describe - a weak alarm signal but no actual problem with the "alarmed" item. IF the batteries are in need of replacement, operating an item on the batteries - head pump, for example - can lower voltage sufficiently to cause that to happen in some cases.

 

[JLR]

Thanks Mike. I will do so but I know the batteries themselves are fine since I just had to replace one. I am just not sure why it only happens when the engines are cold and then again, not every time. Although it can be silenced momentarily with the silence button, it comes right back on when the button is no longer depressed. Also, it changes in frequency (as in how and when it comes on) depending on how long I hold the test button in. Maybe those are clues but I am not sure as to what. ,

 

[bobk]

If you shut them down after the 5-10 minutes and then re-start does the alarm sound again?

Bobk

 

[doc g]

Sounds like a ground issue to me ......Pat

 

[JLR]

Not sure. I have not tried that.

 

[Avenger]

Sounds like a ground issue to me ......Pat

Ditto that. Ground problem or tired sensor, but I think these systems are normally closed, so a sketchy ground would definitely do that.

 

[JLR]

If it were a ground issue, why would it go away when the engines are warm. It would appear to me in the abstract that the draw from the starter on the batteries when cold is what might be causing this. But, I always leave my charger on at dock. I wonder whether the charger may not be putting out properly and only after the alternators charge the batteries is all back to normal.

 

[racclarkson@gmail.com]

Grounds are funny things. I had a bow thruster that wouldn't work, yet it showed great continuity every time I tested it. Bad wire. It was corroded through at a kink; naturally it was in a hard to see location. It did complete the circuit but couldn't carry a load. Talk about a mystery. I could see where heat might expand your wire some to make a better connection and cooling could degrade it. Or maybe the increased voltage after you are warmed up and charging with alternators is a possibility.

Make a jumper and go direct from each sensor to the board (or just before it) when cold and see if you can isolate it. Given the age of these boats, a jumper is something that doesn't gather much dust. Good luck!

 

[SKYCHENEY]

Its a voltage issue. My 12pt gives false alarms and weak alarms like that if the voltage is low. The solution is to power it with a converter that puts out a constant voltage.

 

[JLR]

Sky - can you elaborate please. Let's assume you are correct. You most often are and I appreciate the sage advice of the past, including the entire Vanner lead on my other boat. Why would voltage be low when starting at the dock but not after the engines warm up or are charged underway by the alternators? My only guess is thatthe draw on the batteries is so much greater when the engines are started for the first time? Also, do you have a suggestion for a constant source 12V converter. Thanks.

 

[racclarkson@gmail.com]

Your having replaced one battery is more an indication of a problem than a validation of good batteries. Have you load tested each one?

 

[JLR]

I have not but in this boat, I only have 4 12V batteries and two of them are virtually new. OEM had only 2 batteries and I added the other two. It's possible that one could be on its way out but I have no other indications of a low battery other than the monitor. Of course, the OEM battery gauge shows all are fine with the charger off, of course.

 

[SKYCHENEY]

Sky - can you elaborate please. Let's assume you are correct. You most often are and I appreciate the sage advice of the past, including the entire Vanner lead on my other boat. Why would voltage be low when starting at the dock but not after the engines warm up or are charged underway by the alternators? My only guess is thatthe draw on the batteries is so much greater when the engines are started for the first time? Also, do you have a suggestion for a constant source 12V converter. Thanks.

Try this:

https://dcpoweronboard.com/dc-ups-startguard/

Or maybe better yet, this one:

https://dcpoweronboard.com/dc-power-stabilizers/

I'm not saying that this is definitely the fix, but that I have seen it happen on mine and when it does, its always when I have the inverter pulling off of the battery bank that powers the monitor. Its always when the voltage is just a little bit low. .

 

[JLR]

Thanks Sky. Went out today. Sure seems like low voltage. I let the motors warm at the dock to charge the batteries for five minutes and no alarm after that. One really weird thing though. If I start one motor only, no alarm. If I shut that down and start the other motor only, no alarm. But when I shut that one down and the start both, I get an alarm. I wonder what is common in the electrical system for the monitor that only gives me an alarm when both motors are running?