Raymarine SPX 5 causing excessive magnetic deviation

You might look at using the bulkhead mounting kit as the slot can then go anywhere you can mount the pin. On my installation to get the motor as far away as possible I had to make up a plate attached to the binnacle moulding to take the pin.
 
The symptoms described correspond exactly to those shown by a 2005 batch of S1 and S1G computers that were affected by a manufacturing defect. The cause was a polarized capacitor fitted the wrong way round which resulted in the circuit working like it had not had the capacitor fitted.

The high deviation means that the compass reading jumps, skipping some intermediate readings, making also compass calibration very painful, requiring several turns and hours looking like an idiot going in circles in front of the marina.

I had this same problem with my S1 which I fixed after having found on-line the Raymarine service documentation. After having dissoldered and re-soldered the capacitor the correct way round, with a new re-calibration the deviation went from 16 down to 2 and the autopilot suddenly began to work like a dream.

The SPX-5 is in fact an S1G re-badged. I wonder if it is affected by the same or a similar problem. I cannot believe they fitted another batch the wrong way round, but it could be that the capacitor has become practically ineffective (it may happen to capacitors after a few years). Freezing damp on the component might trigger the demise.

To check if that is the case, remove the compass from the bulkhead and slowly turn it whilst looking at the heading. If that jumps randomly reading a few degrees whilst turning it is likely that your computer is affected (example 110,111,112,113 ... 122, 123, 124, 125 ... 138, 139 ...) . It would be useful to double check using another fluxgate compass, however if that were defective it would not jump by just a few degrees randomly, but it would just fail to read clear sections of headings.
 
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I fitted my spx 5 wheel pilot as per instructions and have had no problem with my ritchie compass mounted above. As the pilot is on a bulkhead I did managed to swing the motor even lower to clear some cables but when sorting out the final position I did not notice the compass deviate unless the motor was very close. The fluxgate compass never matches my steering compass being always a few degrees different but that does not bother me to much as I normally get the boat on course before using the pilot. I also fitted the rudder reference unit. I'm not to sure whether it was worth it and have not bothered to disconnect it to find out in case it tells me the worst !
 
SPX5 wheel drive slots

Trying to find out if its possible to cut another slot to use for the pedestal bracket - one position badly affects the binacle compass, other position power cable cant be fitted as it clashes with engine command unit - anyone out there tried adding another slot ?
 
Well, at least you got an answer! Neither Raymarine nor the (Dutch) importer has ever reacted to my mails concerning this matter.
Chris

If I'm not mistaking the Dutch importer (Holland Nautic) is no longer importing Raymarine as Raymarine now have their own subsidiary in Velp:


Sales, Distribution and Service
Raymarine Nederland
Florijnweg 21G,
6883 JN VELP
Nederland
Telephone: (+31) (0)26 361 4242

Cheers,

Arno
 
In my case there is no difference if the wheelpilot is off: the deviation stays the same. The fluxgate is not reliable as well - sometimes gives erratic readings. But that may be because I don't always have the GPS on, that's linked to the SPX5.

When you say "off" do you mean that you are not using the pilot ie on standby, or that there is no leccy at all going to the pilot? If switching the leccy off cures the problem then its likely that the source is some 12v wires running too close to the compass. If switching the leccy off has no effect then the problem is permanent magnetism in some metal, most likely the magnets in the motor of the autohelm.

Its easy enough to derive a deviation chart. TBH I cant remember the last time I used the compass - thats why god has given us gps.:)
 
You might look at using the bulkhead mounting kit as the slot can then go anywhere you can mount the pin. On my installation to get the motor as far away as possible I had to make up a plate attached to the binnacle moulding to take the pin.

Ok so the orientation of the slot is not critical to the operation of the system ... verrry interesting...... guess like you, I could make a stainless plate to carry the pin so the cable entry is clear or away from the Compass. Have posted a question with Raymarine about cutting a new slot - we'll see what comes back ... hopefully
 
Recieved responses from Raymarine

Good Response from Raymarine (See Below) :- so I can cut a new slot so as to move the drive motor away from the Compass --- Result !!


Response Via Email 01/18/2012 10:54 AM
As long as you do not compromise the workings of it then you can make the placements anywhere as long as you follow the instructions as close as you can in the manual

Customer By Web Form (Paul Chaplin) 01/18/2012 08:01 AM
Understand that the orientation of the wheel drive does not impact the pilot operation, will cutting a new slot in a clear area in the ring also not affect the pilot , or will I have to mount the pin on a bracket away from the Binacle post ?

Response Via Email 01/18/2012 05:04 AM
Hi

You can place the motor slot anywhere you would like, just follow the instructions but place it in a better position on your boat. There is no additional settings you have to make when doing this

Auto-Response 01/17/2012 04:06 AM
The answers to the following questions may be relevant to your question:

Customer By Web Form 01/17/2012 04:06 AM
I am installing and SPX 5 wheeld drive on a Jeanneau 32i both slot positions for the wheel drive are giving problems - one is heavily affecting the binacle compass, and in the other the cable entry can't be made because the end of the motor is blocked by the yachts motor command unit (Throttle etc) which cant be moved.
Question is - can I cut another 'slot' to position the motor in a down to port position or other to miss the problems ?
 
When you say "off" do you mean that you are not using the pilot ie on standby, or that there is no leccy at all going to the pilot? If switching the leccy off cures the problem then its likely that the source is some 12v wires running too close to the compass. If switching the leccy off has no effect then the problem is permanent magnetism in some metal, most likely the magnets in the motor of the autohelm.

Its easy enough to derive a deviation chart. TBH I cant remember the last time I used the compass - thats why god has given us gps.:)

When I disconnect the main switch, the deviation is still there. I checked if some wires were too close to the compass - but no, only the twisted wire of the compass light.
 
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