Lack of wind direction info from MHU

[shortjohnsilver]

I have a B&G networked system that generally has been okay albeit clearly getting old - circa 20 years.

However, over the last year or so I have had this issue where the wind analogue reader will stop showing the correct wind direction at the display head although the display is still providing wind speed. This usually happens when winds are extremely light and variable or/and when it drops to nothing.

I have found that sometimes I can switch off the power to the system and then switch back on and It all restarts providing both direction and speed. All apparently okay.

This time however, again in very light wind conditions I noticed that the display was at odds with the direction although speed was still being indicated and sure enough the analogue needle remained firmly in one place irrespective of power off power on, or course change and increase of wind speed.

I assume that the information sentence has been interrupted at the MHU but this an elderly B&G networked H1000 MHU 496 unit.

Has any other forum member had a similar issue and maybe able to give an idea of correcting it. Replacement of the unit is not feasible really.

 

[pvb]

I assume that the information sentence has been interrupted at the MHU but this an elderly B&G networked H1000 MHU 496 unit.

I don't think there's an "information sentence" as such. The masthead unit will send varying voltages on 3 wires, according to the wind direction. Processing of these voltages happens in the display head to give an analogue wind direction.

Obvious things to check first are the connections; are the Network plugs/sockets free from corrosion? If the connections at deck level look OK, you may want to check the plug/socket at the masthead. If that looks OK, next thing would be to bring the masthead unit down for further testing or repair.

 

[shortjohnsilver]

Of course that makes sense, that’s likely the problem. Fingers crossed it’s a corrosion issue and things need cleaning up,
I’ve had that MHU off before to replace the pcb and there are several pins that must be aligned just so and not easy when swinging about and heights aren’t your thing! Oh well!
Incidentally, is there a gel or some kind of conductive liquid that might assist re maintaining better electrical connection and keep the moisture out too?

 

[pvb]

Incidentally, is there a gel or some kind of conductive liquid that might assist re maintaining better electrical connection and keep the moisture out too?

Tef-Gel is often suggested.

 

[dje67]

B&G Anemometer - Beneteau 393i Oceanis

some info I put on this thread. Also, search for HMU electrical check - don’t have link to hand, but there is a good faultfinding guide (poss on Tinley site).