Robertson Autopilot AP2500 Problem

[seasavvy]

Just the other day I was cruising home and suddenly had a problem with my Autopilot. It went crazy on me. I noticed a large error between the Magnetic compass reading and Flexgate compass reading of 160 degrees difference. Can someone tell me what the problem could be? When I remove the plug at the Flexgate compass, I do get an error indication on the control counsel. So, the Flexgate is putting out a signal but I'm not sure if it's right or wrong.

Has anyone experienced this and can give me some input? I am assuming it is the Flexgate compass but not sure how to check it.

Thanks

Norm

 

[Nick]

If there is anything magnetic stored near the fluxgate or magnetic compass it will affect either. We found metallic spray cans stored by the prior owner in the steps to the fwd cabin adjacent to the bulkhead where the fluxgate compass was mounted.

 

[seasavvy]

Thank you for responding. We don't have any cans or anything metal next to the compass that would cause it to go haywire. But that was a great suggestion. I wish it was just a metal can.

Norm

 

[double eagle]

my experience
check things out but dont spend a lot of $$$$ on it ...
like mine it is obsolete....I tried everything ..
sent all the different parts in to have checked etc ...
just bite the bullet and save for a new one...
I have over $ 3000 $$$$ ove r 2-3 yr period
everybody says they can fix it .....dahhhhhhhhhhhhhhhh
just but a new one
my 2 cents
bill

 

[doc g]

Does your unit run from a Junction box? There is a procedure that needs to done to set the fluxgate in the set up menu. You enter the mode on the set up menu and take the boat in a 360 circle . This I beleive allows the FGC to know what True North is . Then you set the offset to make it read magnetically and give the proper readout at the head. Simrad has a great customer support line at 800.426.5565 . The manual will also tell you how to set it up properly . If I recall correctly there is a Dockside set up menu and a Sea Trial set up menu . It may just need to be set up again. Does it hold a course properly? Will it Navigate to a waypoint ? If so it just needs the offset to be reset..............Pat

 

[polarizer]

You may want to look for a connection between you compass to your helm station. Wires sold in those days were not long enough to make runs from the center gravity spot in the boat all the way to a bridge helm station. you may find one or more connections have possibly come loose. I had a similiar situation and found a small connector had become unconneceted. That was the good news. the bad news was I found it when I was pulling the new wire for my new furano autopilot. My electronics guy told me the unit was shot. I almost shot him when I found the answer.

 

[seasavvy]

Thank you all for your input. I did check all the wiring and everything seems solid. I shouldn't have to recalibrate since I am in the same area. It just went flukey all of a sudden and now it's reading 150 or so degrees off and it's not stable. The compass reading goes up and down. When I disconnect the fluxgate, I do get an alarm that says F-61 which is loss of fluxgate compass. But in normal operation, I don't get the F-61. It's putting out information when connected but not the right information. You think they would have an error message when the compass is not working properly.

Does anyone know if this fluxgate can actually be tested? When we called Simrad, one of the techs said it could not be tested. Then, when we called our local electronics shop, they said they could test it but I don't see how if they don't have the proper setup. I'm leary as to if they can really do this or they just want some money for the day for just testing without really being able to test. You know what I mean.

Norm

 

[Trojan]

I can not beleave that it can not be tested .If its putting out a signal and its not correct there must be some type adjustment. They were not made perfect to start with. You need to find a friend that is into electronics. To look at it.You have the proper setup on your boat to work with.I don't know the unit. Unless it is a dedicated IC I would think it can be repaired. Find an amateur radio operater, they like to work on things like this. Bill

 

[Genesis]

There are VERY fine wires inside those fluxgate compasses which are articulating (they move) with the internal mechanism.

I would not be surprised if these are basically unrepairable if they get flaky.

These units are pretty delicate. I've had mine apart a couple of times. There ARE adjustments, and the circuitry itself is pretty basic, but the precision involved is non-trivial.

 

[Mike36c]

Another thought..... Not sure if you have one but some stabilized SAT TV dishes have outputs for heading information. It may be a short term fix. Mike

 

[Nonchalant1]

Sometimes even reliable electronics get wierd on you, like from a surge in voltage or lightning strike within 1/2 mile of your boat, and need to be reset.

Why don't you just try the setup procedure with running the boat in a 360 degree circle in flat water. You know how sometimes you just have to restart your computer to make it work again?

Doug

 

[doc g]

Mine did the same thing. Read the previous post and your manual. If you do the set-up procedures ,both dockside and sea trial,step by step according to the manual and it still does not work there was an RFC on ebay the other day for about 500.00. Write down all the settings for rudder,counter rudder, transition speed etc. then do a hard re-set on the head. Also if you have two heads disconnect the "other" head and see if it works 1st to see if possibly one head or the other has a problem. I have seen that problem too.

 

[OldHatt45]

Don't know what model your Fluxgate is but I found out something interesting about the Simrad Compasses about a year ago.

The Standard RFC that comes with the AP20/21 has a small problem under certain conditions (headed within 10 degrees of Due North or Due South). THe auto pilot will cause some "S"ing. You can minimize the "S"ing but you can't eliminate it completely. I don't know if this applies to your situation but it maybe something to look at. From what I've been told, the only real fix for this is to step up to the "Better" Fluxgate. I don't remember the model numbers but if memory serves me I think the Standard is an RFC25 and the "Better" one is the RFC35. Maybe one of the other guys can provide more info on model numbers. In the process of moving so have limited time right now.

OldHatt45