NECO Autopilot Update

[ArcticBob]

Boat fitted with NECO 629 autopilot with rotary drive to Whitlock steering. Fitting Raymarine S3G autopilot computer, want to re-use NECO drive unit.

Anyone done this successfully and prepared to share info on modding the drive to run with the reversing voltage type controller??

I have full Installation & Operating Instructions for the NECO NM692 Mk3 system if anyone looking for same...........PM!

 

[SteveA]

Bob,

I did exactly this on our last boat and it worked very well. The NECO drive unit is very powerful. The motor was sent away for modification (think it cost about £100). It was some years ago but I will have a dig through the old records and try and find who we sent it to.

Just checked and it was Greenham Marine - now called Greenham Regis.

 

[ArcticBob]

Thanks for that. I have been speaking to Greenham Regis in Southampton (where I'm based). They want £375 + VAT to do the conversion.

 

[angelsson]

Hello,
I am about to replace my Neco controller but keep the drive unit, I am installing a Simrad AP22, and I am under the impression the drive unit works as the controller reverses polarity to the drive.
From your post it seems that is not the case, am I being mislead that the Simrad will operate the drive this way.

 

[danielefua]

The Neco Drive cannot be driven like a reversing motor. Inside it does not have permanent magnets but two coils (one "shunt" and one "series") that need to be fed with fixed polarity. The change of turning direction is accomplished by reversing the polarity of the "armature" only. You can drive the Neco motor with any modern autopilot that is able to drive "solenoid" valves but you have to keep the existing relays and fit a new third relay to control the clutch and the "shunt" coil. The changes can be made by anybody with a little DIY ability and will cost just the price of the third relay: less than £5.
Whoever needs further directions is invited to PM me and I will be glad to help.
Daniel

ps: angelsson, I realized we are already in touch...

 

[Guitarrich]

Neco Success with S3G

Ahem...I too have a Neco drive on the yacht I bought last October. The previous owner had tried to employ a Navman pilot brain but had failed to get it working. He ended up with a Raymarine ST4000 wheelpilot. He said it worked for him, but I hate wheel pilots so was determined to make the Neco work......

First I tried a Raymarine "SOL" pilot. This is designed to output a reversing signal suitable for SOLONOIDS - such as is found in some modern hydraulic steering systems. Unfortunately, and it might have been due to some earlier fiddling, I couldn't get it to work.

I studied the Neco wiring diagram and came to the realisation that "danielefua" has articulated vis permanant magnets - or lack thereof.

However, I also decided that there ARE points in the circuitry where a conventional reversing polarity might be applied. With the wheelpilot at the back of my mind as a back-up plan - I started taking stuff out of the Neco box. I removed the relay assy and the associated wiring. I then put 24 volts on a pair of probe wires and started poking it on likely cable pairs inside the box. (Bear in mind I'm straddling the generator and leaning across the back of the washing machine.......)

Before too long I found a pair that caused the motor to turn. I reversed the wires and it turned in the other direction. SUCCESS! The rest was more scientific and fairly straightforward. A ballast resistor to drop the voltage for the (12volt) clutch and I was there.

I used the pilot almost every day from March to October and it worked like a dream apart from the drive chain. I'd bought a chain from a moped shop once I found I had an answer for the electrical side of things. The chain was fine until halfway through the season when with a big wind and following sea it started to jump. A sickening sound! I was driven back into the engineroom by my wife and straddled myself across the washing machine etc as before. Then I noticed that the whole drive is mounted on a hinged plate. It was a slow and painful process wheedling in there with spanners but I finally hinged the plate up a bit more and I got a freshly laundered pair of testicles into the bargain! I'm now in Marmaris and looking to replace the cogs as a matter of routine. Afterall, they're 30 years old, and the Turks are great at this sort of thing.

 

[danielefua]

...
First I tried a Raymarine "SOL" pilot. This is designed to output a reversing signal suitable for SOLONOIDS - such as is found in some modern hydraulic steering systems. Unfortunately, and it might have been due to some earlier fiddling, I couldn't get it to work.
...
I studied the Neco wiring diagram and came to the realisation that "danielefua" has articulated vis permanant magnets - or lack thereof.
...
Before too long I found a pair that caused the motor to turn. I reversed the wires and it turned in the other direction. SUCCESS! The rest was more scientific and fairly straightforward. A ballast resistor to drop the voltage for the (12volt) clutch and I was there.
...

Your post is very interesting and I wish you could explain more because although some of your explanations are clashing with my present knowledge I am ready and willing to change it.
1) "Solenoid" output is, usually, a non-inverting output. It is made to control an ON/OFF device insensitive to polarity unless provided with clamping diodes which should be accounted for.
2) Sorry but I don't understand your phrase regarding me and the magnets, possibly my fault. Do you argue that inside the Neco Drive there are indeed permanent magnets?
3) I cannot but believe that your Neco presently changes turning direction according to the autopilot but I really wish you could indicate the pair of terminals that do it. Possibly referencing to the original Neco schematics.
4) If the motor reverses, a possible explanation is that indeed there are permanent magnets but, in this case, I wonder what are the Shunt/Series coils there for.
5) Another possibility is that while probing around with 24V you were also actually feeding a fixed voltage to the Clutch (by default paralleled to the Shunt coil). That would clarify my doubts but it seems somehow ruled out by your next phrase regarding the ballast resistor etc.


I wish Derek Coventry could join this discussion. He is the only person in the world that knows exactly the innards of the Neco drive; I am just a passionate self teaching apprentice!

Regards
Daniel

 

[Guitarrich]

Neco drive - puzzling!

Daniel,
You clearly understand this situation more than most. Derek was very helpful when I contacted him last year, but I got the impression that he was also quite frail. He also confessed to being a little overwhelmed by the complexities now.

I admit that my assertions sound literally incredible, and I'm now going to have to open up the wiring box and find out what I did exactly. However, the boat is on the hard in Turkey, and I don't plan to return until March. We'll have to wait until then.

But, to address your specific points:

1) The SOL output was, I think essentially to close one relay (port) or the other (starboard). At any rate I couldn't make it work.
2) No, I'm still under the impression that there are no permanent magnets.
3) I will indeed answer this when I get back to the boat. I should have made a note of the terminals. It's just possible that in actuating the clutch I'm also energising the windings. I admit that there were bits I still didn't understand, but was so happy it worked that I replaced the cover and moved on!
4) No, I DO have the schematics and there are no permanent magnets.
5) The ballast resistor may be wired to the clutch actuator so that the voltage across the shunt is still 24v.

If there are any other Neco aficionados reading this, I have a spare compass and compass wiring loom recovered from the boat that I wish to dispose of......

 

[danielefua]

Thank you Guitarrich for your kind reply.
I had several mail exchanges with Derek and he is indeed the person with the best knowledge on the Neco. It is a pity if he does not feel to work on them anymore.

Regarding your case I am pretty much convinced that during your attempts you probably powered the Shunt Coil with a steady current and the Armature with a current that reversed according to the autopilot "brain". You did not power the Series Coil. In this configuration:
1) you powered the Armature with a too high voltage. The Armature should be powered in series with the Series Coil so that the input voltage is actually partitioned between the two elements.
2) the internal fixed magnetic field is weaker than due. In the normal configuration the actual magnetic field is the sum the Series and the Shunt Coils magnetic fields.
The two points actually counter balance and the final torque you get from the motor might be very close to what you need. Unfortunately there are few drawbacks the worse of which is that you may burn the Armature in the long run. The other is that there is a sort of feed-back between the Series Coil and the Armature that you miss. The latter problem is probably not as important as the former.

Lately I wrote a short note on how to match a Neco Drive to a modern autopilot brain and a kind "forumite" helped me to correct few errors. I will be very glad to send it to whoever needs it and I will appreciate all kind of suggestions on how to improve it.

Beside this I am pretty familiar with the 692 Neco system itself and will be glad to help anyone with some DIY attitude to fix it in case of problems. Just write.

Daniel
swan411 dot 004 at gmail dot com

 

[wb323381]

Neco 692 Parts Wanted, Have Manual

I'd like to buy spare Neco 692 parts.

I have scanned a 692 manuak if anyone needs it.

Bill

 

[Guitarrich]

I've got the old Neco "Transmitting Compass" off my boat, now taking up space in the garage. Anybody want it? Swap with something??

 

[danielefua]

Hello,
I am about to replace my Neco controller but keep the drive unit, I am installing a Simrad AP22, and I am under the impression the drive unit works as the controller reverses polarity to the drive.
From your post it seems that is not the case, am I being mislead that the Simrad will operate the drive this way.

Hi angelsson!
How is your work proceeding? ...keep us posted!

Daniel

 

[pcatterall]

Very timely thread guys; well done!! My 'new' boat ( a Neptunian 33) had been fitted with NECO which drove the steering via a chain. The last owner replaced the system with a Raymarine (6000 I think) even though the NECO was still working ok. The motor is still fitted and I have seen the 'compass' in a locker but not sure if any other bits have survived.
I did think that it was a shame as my previous boat had the same system and I thought it was great!
Is there any point in my keeping the bits I have and is it worth/possible to think about getting the system to work?

 

[danielefua]

Very timely thread guys; well done!! My 'new' boat ( a Neptunian 33) had been fitted with NECO which drove the steering via a chain. The last owner replaced the system with a Raymarine (6000 I think) even though the NECO was still working ok. The motor is still fitted and I have seen the 'compass' in a locker but not sure if any other bits have survived.
I did think that it was a shame as my previous boat had the same system and I thought it was great!
Is there any point in my keeping the bits I have and is it worth/possible to think about getting the system to work?

Please explain better and I may help.
The critical question is: is your system presently working?
If yes: does the Raymarine "brain" commands a properly modified Neco drive or does it commands an additional servo mechanism and the Neco is just idly following?

No doubt that it is possible to get a complete Neco system to work again and, very likely, at a fairly low cost; depending on the actual presence of a functioning autopilot and the status of your Neco "bits" it might be worth or not.

Daniel

 

[Guitarrich]

....and as you may have seen, I've promised Daniel to try and figure out exactly HOW i got my Neco chain-driven motor working. I have a 24v system, and I know there's a ballest resitor in there somewhere for the clutch.

After studying the cct diagrams from Neco, I actually gave up for a while. Then I pulled out the relay cluster from the box on top of the motor and blundered about with 24 volts. Suddenly the motor jumped. I reversed my roaming lead and the motor jumped again the other way. The sun came out and the birds started singing.......

Now if only I'd clocked the fact that the chain can be adjusted by tilting the mounting plate, then I wouldn't be looking for a new cog for my intermediate steering box - which is the point the Neco drives from, (in the engine room).

Apart from the jumping cog - should be easy to get a replacement manufactured - the 30 year old drive has funtionned silently and perfectly through last years' continuous cruising.

I'm making a bit of a rod for my back, but I'll take careful note of where my wires ended up and post it up here. This will be about three weeks from now.

I think I'd stick with the Raymarine "brain" if you can, and if you want to build in redundancy, then get a spare brain. I'm not sure about the S2, but the S3 or SPX 30 will certainly drive the Neco motor. (The S1 would be too light I think.)

 

[pcatterall]

Thanks Daniel. I've only just bought this boat and she is not with me untill Monday I will then begin a full investigation. It was working 2 years ago and I hope all the bits are on the boat. The last owner just installed the Raymarine as he thought the NECO was old fashioned!

 

[danielefua]

I'm making a bit of a rod for my back, but I'll take careful note of where my wires ended up and post it up here. This will be about three weeks from now.

I think I'd stick with the Raymarine "brain" if you can, and if you want to build in redundancy, then get a spare brain. I'm not sure about the S2, but the S3 or SPX 30 will certainly drive the Neco motor. (The S1 would be too light I think.)

I don't forget your promise and I will be here, ready...

Regarding the Raymarine S's I am pretty convinced that the best way to connect them to a Neco motor is by keeping the relays; therefore the power output of the "brain" should not be relevant.
Notwithstanding, buying from the start a properly dimensioned "brain" for one's boat is a wise attitude because in case of the Neco drive failure, a well dimensioned new servo can be acquired later.

Daniel

 

[Simes]

Have you tried Navitron Systems

I believe that the designer of the Neco autopilot (as used on many a Camper & Nicholson?), is the MD of Navitron Systems. Maybe he can help?

www.navitron.co.uk

Simes

 

[sailor22]

NECO 692 Auto pilot

A good thead for those of us who still have these systems.

1. I mis-connected the drive from my replacement Cetrek controller in drive mode vice relay/spool valve mode and think that I have wrecked the relays and diodes. Anyway it only works if I operate the relays manually.

Has anyone got a drive unit or the relays and diodes that they can help me with so that I can get my correctly connected system working.

2. By the way, my relays seem to have two contacts which operate when the relays switch. The main one seems to operate the drive, but without digging the drive unit out of the aft confines of my engine room and dismantling the unit, I cannot find out what the second contacts do in progressing my fault-finding/ rectification. Does anyone know?

 

[danielefua]

A good thead for those of us who still have these systems.

1. I mis-connected the drive from my replacement Cetrek controller in drive mode vice relay/spool valve mode and think that I have wrecked the relays and diodes. Anyway it only works if I operate the relays manually.

Has anyone got a drive unit or the relays and diodes that they can help me with so that I can get my correctly connected system working.

2. By the way, my relays seem to have two contacts which operate when the relays switch. The main one seems to operate the drive, but without digging the drive unit out of the aft confines of my engine room and dismantling the unit, I cannot find out what the second contacts do in progressing my fault-finding/ rectification. Does anyone know?

It is very unlikely that you burnt the relays by inverting the voltage but you may have burnt some diode. Some units are fitted with clamp diodes across the relays; in case of reverse voltage they will burn. Substituting them is very simple and cheap: few cents.
I am sure I can help but you will need to have full access to the relay box on top of the drive unit and will need to carry some easy test with an ohmeter.

I suggest you write to my e-mail address I wrote in a previous message.

I am curious: do you have a Neco Drive Unit that can work either with the original Neco Control Unit and a Cetrek "brain" with simple adjustements? I know well that it is feasible but I always considered it rather messy.

Daniel