Challenging Raymarine ST60 Wind Instrument Problem

[manlyp]

Help required to diagnose problem with ST60 Close Hauled Wind Instrument.

Symptoms. Wind direction working properly. Wind speed showing zero. I've replaced PCB in masthead unit and these are my voltage readings to earth. Yellow (wind) 8V, spec is 0 to 5V. Other wires to spec. Disconnecting yellow from instrument head gives a very low masthead unit output voltage, circa 0.1V variable in 10Kn wind. The open circuit yellow on instrument is just over 8V.

I have swapped the master instrument head with the slave instrument and had identical results prior to replacing the masthead PCB. Is it possible that the original masthead unit blew both instrument heads prior to its replacement?

 

[cmedsailor]

Help required to diagnose problem with ST60 Close Hauled Wind Instrument.

Symptoms. Wind direction working properly. Wind speed showing zero. I've replaced PCB in masthead unit and these are my voltage readings to earth. Yellow (wind) 8V, spec is 0 to 5V. Other wires to spec. Disconnecting yellow from instrument head gives a very low masthead unit output voltage, circa 0.1V variable in 10Kn wind. The open circuit yellow on instrument is just over 8V.

I have swapped the master instrument head with the slave instrument and had identical results prior to replacing the masthead PCB. Is it possible that the original masthead unit blew both instrument heads prior to its replacement?

Some years ago I had similar problem. Wind direction OK but wind speed showing "- - -". I replaced the whole wire and since then it's fine. Sorry I cannot help more.

 

[manlyp]

Further thought .... Can anyone confirm whether or not there is a pull up resistor on the input to the the instrument?

If so this might explain symptoms if the wind wire has gone high resistance but not open circuit. If the masthead unit effectively shorts the cable to earth depending on the wind speed this might be how it is intended to work.

 

[AngusMcDoon]

I'm on my original ST60 wind instrument after 15 years. Had 3 new mast head units and 2 replacement displays, but apart from that, it's all original.

 

[FWB]

Give Raymarine tech a call 01329 246777 option 2.

 

[nigelmercier]

There is a lot of duff info in the Raymarine fault finding method, see http://www.ybw.com/forums/showthread.php?423581

 

[manlyp]

Are these comments relevant!

 

[FWB]

Are these comments relevant!

If you want a solution then my comment about phoning Raymarine is relevant.

 

[manlyp]

Quite right. The other comments are largely irrelevant!

 

[RichardS]

Quite right. The other comments are largely irrelevant!

This forum is a free resource and people are trying to help in whatever way they can. Ultimately, it's up to you to decide what is helpful and what is not. I doubt that your attitude will encourage people to help.

Richard

 

[nigelmercier]

Further thought .... Can anyone confirm whether or not there is a pull up resistor on the input to the the instrument?...

Whole bunch of Raymarine Service Manuals here, with circuit schematics http://www.pic18c.org.uk/downloads/RSM.zip

And I suggest you change your attitude.

 

[manlyp]

Seems there are new models and two different designs of st60 out there, so conversation with Raymarine was a bit inconclusive. We now believe fairly new certainly cable fault. Raymarine support limited to measuring aavoaltage, checking status of instrument e.g not VMG a or finger trouble, but did not seem to know how circuit worked at each end.

 

[nigelmercier]

Are you actually reading the replies in this thread, or just trolling?