Raymarine ST60+ API going "crazy"

[RobertSchuldenfrei]

Hi Forum Readers,

I have a two year old Raymarine ST60+ API that is going "crazy."  Here is what I "think" I know.  When I arrive at the boat and power up the instruments, the ST60+ works fine.  For example, today it read 5.0 knots with the wind coming out of the East.  Then I turn the motor on and the direction needle goes "nuts."  The wind speed show --- in the LCD.  If I cycle through the programs they display correctly and the instrument goes to OFF on command.  Any idea what is going on?

Thanks,

Bob

[Roc]

I would call Raymarine and tell them the software version you have. 

[Ken Juul]

Starting the engine drags the battery voltage down below what the instruments need so they go off line is what is happening.  Why is the question.  It could be the batteries getting tired.  Could be corrosion on the St 60 power leads so it just thinks the voltage is too low.  Will take some digging.  Same thing used to happen to my chartplotter when starting the engine.  I added a dedicated start battery as part of my electrical system upgrade.

[Ralph Masters]

I too have added a dedicated start battery and no longer have the GPS go off line when starting.

The other benifit is that the engine starts easier, takes less time to heat the glow plugs. 

Ralph

[RobertSchuldenfrei]

I too have added a dedicated start battery and no longer have the GPS go off line when starting.

The other benifit is that the engine starts easier, takes less time to heat the glow plugs.  

Ralph

Hi Everyone,

Well, the API was working today!  Don't you just love intermittent problems .  It may have something to do with the engine starting.  We do have a battery bank for engine starting, but I am going to have to look at the way the house batteries and the engine start batteries (along with the instruments circuit) are wired.  This was all done by the PO and Franco has done all of our systems work.  I am having some health problems once again, so I may not get to it for a little while.  Will keep you posted.

Cheers,

Bob

[tonywright]

Thinking about this device, and what happens when you start an engine. You have three connections for a very low voltage signal. One at the top of the mast, one in the base of the mast, and one at the instrument panel. If any of these connections is bad, you will not get anything on the display. If any connection is loose, you will get an intermittent display.  Starting the engine causes vibration....

A thought

Tony

[RobertSchuldenfrei]

Well it has work well for a couple of weeks now.  Don't you just love "gremlins?"  Will keep watching it, but I have other issues with which I must deal.  See Garhauer track car.

Cheers,

Bob

[RobertSchuldenfrei]

I have an answer.  This is from my log notes:

Saturday, November 15th the 178C (GPS) started to flicker at a rapid rate.  Paul Ferrara was on board.  He is an EE.  He suggested that it was the display transformer, which would have been a bummer ($600. for a new GPS).  This is the second instrument on the same circuit to "go bad."  The API has had fits lately.  Today Franco wanted to clean the contacts on the tachometer as it was acting up also.  When he did so, the GPS worked fine.  Answer:  High resistance on the instruments circuit did not allow the GPS transformer to boost the voltage in order to correctly drive the display.

Hope this is the answer.