Knot Gauge Connection

[BungalowBill]

I am trying to find someone familiar with the connections on the backside of an Autohelm Knot meter, vintage from the mid 90's. On my boat I have the Knot gauge and the depth gauge mounted side by side on the cabin wall near the companion way door. The wires are run in the space between the inner and outer walls. The knot meter was starting to get 'flakey' and the display would go blank until I would tap it. I decided to check the wiring so I pulled the gauges off the wall. There are 3 wires on the back of each gauge, one wire ties the gauges together. The wires run from the back of the gauges for about 5 inches then they connect to longer wires via little plastic multi-pin connectors. These wires lead down into the bowels of the boat eventually to the transducers. The Knot meter has one its wires disconnected, or at least I am assuming it is disconnected because it has the male end a 3 prong connector. I cannot find the other side to this wire. I have even cut 3 small holes in the wall on the cabin side of this wall looking and hoping to find the other end. I can find all the other wires but not one to match up the 3 pronger.

Does anyone know if this connection is needed or is it and extra connector that would connect this guage to another gauge? Like maybe a wind speed or ???

I hate to keep cutting holes in my cabin wall looking for a wire that does not exist.

Now the symptoms are the depth gauge still works great, the knot meter is dead and never comes back to life when I tap it. It seems to me there must be another wire but I cannot find it.

Sorry for the long post but I thought someone out there might be familiar with these gauges.

 

[Taylor]

Autohelm manuals for retired products

Looks like Autohelm is part of Raymarine. Have a look at this link:

http://www.raymarine.com/Default.aspx?site=1&section=3&page=179

And see if you can find your knot meter there. I think the owners manual might help you figure out what plug is which. It also looks like Some Autohelm knot meters were networked products with Seatalk, so it might be the unused connector is part of that. You might not even need it.

BTW - if it goes *blank* it sounds like strictly a power problem.

 

[Joe]

bungalow bill....

... it sometimes helps to mention the wire color. Three wires... power ground, data. if the power is red and the ground is black, the other wire is the data wire from the transducer, perhaps blue, or yellow? try describing the problem using the wire colors. The disconnected wire could be a data wire to the wind indicator...

 

[BungalowBill]

All Black

Thanks for all the input. The wires are all have black coating. One has a 5 conductor/pin connector, the other one has 3 pin and the that is daisy chained to the depth gauge. The other 3 pin is the one that was not connected to anything. I did look up the manual on the website and now am convinced the disconnected 3 pin wire is to be used for connecting to another inline gauge. I am going to put a meter on the 3 pin wire and see if I have a power loss problem. At some point I will have to patch the holes I made looking for the nonexistent wire. Once again thanks for all the input, you guys are great!

 

[Joe]

bungalow bill....

if you carefully split open the covering you'll see colored wires inside. If you have a faulty connector and want to splice in a new one you'll need to know what's hooked up to what. Good Luck.

 

[Bill Roosa]

transducers and SeaTalk

The instruments have transducers and also talk to each other via the SeaTalk cable. the cable connecting the two is the seatalk one. the other cables are the individual transducers for each instrument and the power. SeaTalk will also provide power to the units so there may not be a dedicated power cable.
Seatalk is a Raymarine data transmission buss which allows you to do all kinds of things like:
turn on all the lights on all the instruments from any instrument
share data on other (Raymarine) instruments where that makes sense (not your case)

The old SeaTalk cables (round connectors) and the new SeaTalk cables (crescent connectors) are compatible but have to be "neutered" before they will mate!

I'd check out the transducer on the knotmeter before I went any further. it is most likely stuck and just not turning due to marine growths. you can pull it while in the water by just unscrewing the keeper nut and pulling it straight out. There should be a dummy plug to put in the hole to keep the water out while you clean it or use a rag.