Raymarine help please

[tjc]

I have just bought a new to me but secondghand boat and it has a fairly comprehensive suite of Raymarine instruments fitted. However I have some problems and it appears to be the wrong time of year to need an engineer. 5 or 6 weeks in Plymouth!!
I have a
RL70 C radar Plotter
ST 60 Depth, Wind, Tridata, Compass
St6001 Smartpilot
Course computer and heading sensor
Ray 120 GPS

The problems is
1 The plottert keeps losing GPS signal every few minutes
2 The depth reading is intermittent and reads ---- or just flashes the last depth
3 The compass is miles out, about 180 deg but this varies

The problem all seem to be linked. I will have a go myself this weekend but any help or advice would be very much appreciated beforehand

Thanks

 

[npf1]

A few random thoughts.

Raymarine's support dept in Portsmouth are usually very helpful and well worth a call.

Re 1, a few years ago there was a Raymatine GPS antenna that they ended up exchanging (recalling???) because it suffered symtoms similar to the ones you describe. I can't remember if it was the 120 model but that might be something to suspect. Also, probably worth veryfying that it has been installed in a suitable location. Might also be worth seeing if there's been any water ingress into the antenna - but check all the simple things first.

Re 2. This happenned to me a while back. Turned out that the ssstem was working perfectly, just that depth sensors sometime struggle with some types of muddy seabed conditions. As soon as I moved from that area, the problems disappeared. Might also be worth cleaning all electrical contacts on the system and any weed/fouling from the transducer.

Re 3. The first thing I would try is to calibrate the compass as per the manual. It's a simple process that requires driving around in circles for a few minites after pressing a particular button sequence. Before doing so, physically check the location of the fluxgate sensor to see if anything magnetic has been placed in close proximity to the it (for example a ferrous metal object placed in the same locker/space).

Good luck.

 

[Gypsy]

Your setup is very similar to mine.

First make a diagram of connections, most of it will be SeaTalk cables.

Make sure the screwed power connections to the Autopilot course computer (CC) are tight as this is the one thing which is common or connected to all three measurements.

Measure the voltage going to the CC and then coming out of the SeaTalk bus at the CC. There are two ST outputs, measure between Red and Grey and note the voltage. It should be the same as your Aux battery at that time (typically more than 12.5V). If this is low or varying, it could be a clue/cause.

I suggest you try as many instruments operating in isolation as possible then work back from those results. e.g. connect only GPS and Chart to the CC with ST. Leave the other instrument off the bus. If the GPS is stable you there may be another instrument on the ST bus which is creating interference.

Look at the GPS Set-up area on your chart system. It has a display of the satellites Rx, signal strengths and which are in use. If these are low or flakey it will point to the GPS head/antenna or perhaps even back to a low supply voltage.

The Depth needs only +/-12V to operate standalone. Try to operate it standalone from a different power source and without the ST (yellow wire) connected.

Compass - be sure there are no metal objects anywhere nearby. My compass went off 30deg when a camera was left in a bag about 50cms from it.

It is not rocket science. Take it step by step and make notes along the way. Hint - Usually the CC provides the power for all the ST instruments. Each passes the power on to the next instrument. The Chart/Radar does not provide power on its ST connector, it just expects to Rx ST on the Yellow and Grey pins.

 

[AliM]

Try the above advice first, to see if you can sort it all out - it's almost undoubtedly a dirty connection. however, if all fails:
Look at Raymarine's web pages and follow the links to the technical helpdesk and post an enquiry. They are very helpful.

 

[alan]

I would expect all your instruments to be linked via Seatalk .... including the power..... in a ring type system.
Try measuring the volts on the seatalk connector on the last instrument in the chain and see if this is about the same as your service battery(ies).

One "trick" I have seen a Raymarine agent perform is to connect a 12v supply (from same batteries) to the last unused Seatalk connector in the chain, thus feeding 12v from both ends of the ring .... this sometimes helps to overcome volt drop/ bad connector problems.

Alan.

 

[tjc]

Thanks for all this - really helpful. It seems to be pointing in the direction of an electrical fault. Someone at the Marina mentioned a faulty GPS batch of receiver. Test meter to hand Saturday will be interesting