Raymarine ST4000+ XTE increases

[Andrew G]

Hi, I have a venerable Raymarine ST4000+ Autopilot (connected to a SL631 chartplotter, a tiller pilot and ST60 instruments via SeaTalk1). When heading to a waypoint the XTE sometimes continuously increases (instead of staying near zero). This occurs in any conditions (light or heavy) or under motor - so it is not boat trim. My guess is a sick autopilot but do any of you have any suggestions?? Thanks Andrew
(PS: This is my second go at sending this - apologies if it is a duplicate)

 

[FulmarJeddo]

I'm not familiar with the ST4000, I have the later SPX5 with ST6002 display. I have just looked at the online manual for the ST4000. Does it appear to be going into track mode and cycling through Locked heading, Distance to Waypoint and XTE on the display? If it does, it is receiving the data from the plotter and I would guess not processing it correctly, suggesting the pilot is faulty. If not cycling through the Heading, Dist to WPT and XTE, it is either not switching to Track mode or not receiving the data, which could be a wiring fault between the plotter and the pilot. Another point, is it holding Auto mode correctly? ie keeping to a compass bearing.

 

[Andrew G]

Hi FulmarJeddo, I'm not sure what you mean by "cycling" through locked heading etc. Unless you press "Disp" to call up each display it only shows the one you have selected - but yes you can select each in turn.
It is misbehaving in Auto mode, heading to a waypoint, that the XTE progressively increases. I don't know how I could tell if it was keeping to a heading correctly? (I sail on Port Phillip, Melbourne, which is tidal, and there is potentially always current or leeway that could mask any transits etc. I suppose I could set it on a bearing and then dramatically alter sail trim and see how it behaved). If I set it on a heading, remove the tiller pilot and hand steer to an incorrect heading yes it will try to correct (but I can't tell how precisely). When heading to a WP this correction progressively deteriorates and the XTE builds until it alarms.

Thanks, Andrew

 

[johnphilip]

My wheelpilot (ST4000) works perfectly when just put on auto, however when told to track to a point (from Garmin plotter) it starts by going miles off in one direction, eventually corrects and goes too far the other way before settling down to go straight within a few feet. A friend has had a similar phenomenon. Is this what is happening with the OP?

 

[Andrew G]

Hi JohnPhilip, No - my problem is less dramatic, and don't forget that my gear is all Raymarine, taking Seatalk1 (not NMEA 0183 as I guess yours is?). When I tell it to track to a waypoint it does so, nicely, but over time I can see the XTE building (it should be near 0.00 in ideal conditions all the time) so that it can get to say 0.5 nm in say 30 min. I single-hand and this is just not reliable enough. I'm trying to decide whether to get a new Autopilot (or could it be something else??)Thanks, Andrew

 

[FulmarJeddo]

Hi FulmarJeddo, I'm not sure what you mean by "cycling" through locked heading etc. Unless you press "Disp" to call up each display it only shows the one you have selected - but yes you can select each in turn.
It is misbehaving in Auto mode, heading to a waypoint, that the XTE progressively increases. I don't know how I could tell if it was keeping to a heading correctly? (I sail on Port Phillip, Melbourne, which is tidal, and there is potentially always current or leeway that could mask any transits etc. I suppose I could set it on a bearing and then dramatically alter sail trim and see how it behaved). If I set it on a heading, remove the tiller pilot and hand steer to an incorrect heading yes it will try to correct (but I can't tell how precisely). When heading to a WP this correction progressively deteriorates and the XTE builds until it alarms.

Thanks, Andrew

Hi Andrew,
I got the cycling bit from page 20 of the manual from http://www.raymarine.co.uk/view/?id=1836 From what you are saying it sounds as though it is staying in auto mode and just keeping to the heading rather than entering tracking mode, and not tracking to the WPT and compensating for the tide. Do you get any response when you press the +10 and -10 keys to indicate it is in Track mode?

johnphilip, I use a Garmin plotter to my SPX5 and get a similar reaction to what you describe if I delay putting the autopilot in track mode after setting "Navigate to" on the plotter. You can easily wander quite a bit off the track in a few seconds and it seems to try and correct itself immediately rather than gently. I now select "Navigate to" and immediately press the track button on the autopilot and its not as erratic. It's also made it easier now I have moved the plotter closer to the Autopilot control.

David

 

[Andrew G]

Hi David,
It has been happening even after it has been happily heading to a waypoint with zero XTE (in a tidal area) for some time (hours) - you will just see that its XTE starts to build. You have given me something to check as I don't normally fiddle with the +/- 1 or 10 when it is heading to a WP (of course I do when on a heading). I would expect it to alter course for a while but then progressively come back to a zero XTE after a few minutes. The whole system has done a lot of work as I've been 2/3 rds around Aus, around Tassie, Melbourne to Cooktown etc. (all single handed). (One problem is that I'm about to lend my chartplotter to a friend for a few months but I can use my back up Garmin h/h to do some testing. This would also be useful to check where any fault lies).
You have helped convince me that it is not yet time to go and get a new unit. I'll get back to you when I've fiddled a bit more.
Thanks, Andrew

 

[djh1962]

Hi David,
It has been happening even after it has been happily heading to a waypoint with zero XTE (in a tidal area) for some time (hours) - you will just see that its XTE starts to build. You have given me something to check as I don't normally fiddle with the +/- 1 or 10 when it is heading to a WP (of course I do when on a heading). I would expect it to alter course for a while but then progressively come back to a zero XTE after a few minutes. The whole system has done a lot of work as I've been 2/3 rds around Aus, around Tassie, Melbourne to Cooktown etc. (all single handed). (One problem is that I'm about to lend my chartplotter to a friend for a few months but I can use my back up Garmin h/h to do some testing. This would also be useful to check where any fault lies).
You have helped convince me that it is not yet time to go and get a new unit. I'll get back to you when I've fiddled a bit more.
Thanks, Andrew

Hi Andrew,

I have an Autopilot st4000+, with all Raymarine equipment, but a wheel driven system.

I have been having similar problems with general course keeping in all modes, however I suspect is more to do with setup as it does improve with time and particular setup and will play soon with it to determine route cause. Helps a bit that I'm a controls systems engineer.

I would suggest that if you get the correct Xtrack error shown on the Autohelm page, that matches that of the plotter, then its a fair chance that its not a comms issue with the plotter itself, as its replicating that xtrack data, showing the pilot which way it should try and compensate etc. It should also say on the display unit the mode its in? Do you use vane mode and does it work ok following that?

Coincidently, I will be visiting my best friend in Melbourne this year, where we are staying on Phillip Island for Xmas, really looking forward to it

Br Nairndale

 

[Andrew G]

Hi djh,
thanks for that. More variables to try. Yes I do use vane mode but not since I noticed the problem (it is winter down here, very cold and wet at present). From memory the numeric XTE on the plotter and the display are the same - which means that the display/pilot unit is getting the message but is not controlling the tiller arm correctly (I have a spare arm so will try that too).
It might be setup (that would be good) as I have had the gear off the boat to bench test some Seatalk comms, but I also blew a fuse during a Chinese jibe off SE Point Wilsons Prom. (lost everything at 0200 and had to steer by iPad until I could replace the fuse).
As the plans for your visit evolve PM me and we might catch up (my brother is at Newhaven Yacht Squadron on Phillip Island and my boat is at StKilda).
Cheers, Andrew

 

[macd]

My wheelpilot (ST4000) works perfectly when just put on auto, however when told to track to a point (from Garmin plotter) it starts by going miles off in one direction, eventually corrects and goes too far the other way before settling down to go straight within a few feet. A friend has had a similar phenomenon. Is this what is happening with the OP?

That sounds like the fluxgate calibration is way off (particularly if it always darts off initially in the same direction, i.e. to port or to staboard). How does it's reading compare with the boat's compass?

 

[FulmarJeddo]

That sounds like the fluxgate calibration is way off (particularly if it always darts off initially in the same direction, i.e. to port or to staboard). How does it's reading compare with the boat's compass?

Mac, As I said previously I had the same issue with my SPX5 initially diving off to get on track. I initially couldn't get my Fluxgate compass to calibrate. I initially mounted it on the end of the saloon table, which was nice and central in both ways, but also just above and between my twin keels. I moved it a bit higher and further from the keels in to the hanging locker that enabled me to get it much closer calibrated to the boats compass. I'm now wondering if that is the reason that I no longer get the erratic settling down that I use to get. I thought it was down to the way I was operating it. I will try this weekend.

Andrew, Wow 2/3 the way around Aus is some distance. Strangely, we dropped our daughter off at Gatwick Airport last night heading for Melbourne and then on to Alice Springs. She had just popped home for 4 weeks to attend 2 weddings and is returning to continue her 12months of backpacking around Aus, ending in NZ in January/February.

David

 

[djh1962]

Hi djh,
thanks for that. More variables to try. Yes I do use vane mode but not since I noticed the problem (it is winter down here, very cold and wet at present). From memory the numeric XTE on the plotter and the display are the same - which means that the display/pilot unit is getting the message but is not controlling the tiller arm correctly (I have a spare arm so will try that too).
It might be setup (that would be good) as I have had the gear off the boat to bench test some Seatalk comms, but I also blew a fuse during a Chinese jibe off SE Point Wilsons Prom. (lost everything at 0200 and had to steer by iPad until I could replace the fuse).
As the plans for your visit evolve PM me and we might catch up (my brother is at Newhaven Yacht Squadron on Phillip Island and my boat is at StKilda).
Cheers, Andrew

Hi Andrew, we may well catch up, as chances are I will be in both those Marinas at some point, for a look, prior to going to Hobart to catch the boats coming in from the race on 28th Dec

Good luck with your ST4000 !