My RayMarine Autopilot ST4000+ Does a "Crazy Ivan"

Don S/V ILLusion · Sep 1, 2013

Raymarine is probably right. A voltage drop is the typical reason that happens. If you are only seeing 12 v at the input, there is probably a bad connections somewhere since fully charged batteries would be closer to 13 v.
I'd go through all the wiring and all connections to see how much power you are losing compared to the voltage measured at the batteries.

Benny17441 · Sep 1, 2013

Operates well while the engine is running and then becomes erratic once the engine is off. It is definitely a power issue. It seems you may have voltage fluctuations in the circuit. The voltage may intermitently drop below the minimum required for the unit to operate. Start by checking the condition and state of charge of the batteries. Take voltage readings at the point of connection for the autopilot, both with the engine running and off. The readings should be close to 12.6V and 13.3V. The Owners Manual should indicate the required Voltage range for the unit to properly operate. I have seen circuits that test OK while the boat is berthed but you take the boat out and allow for the hull to start flexing and all of a sudden voltage drops appear. If everything else fails just run dedicated wiring to the unit and do not forget to place a fuse close to the positive (+) connector.

Ken13559 · Sep 1, 2013

My old ST4000 MkII did the Crazy Ivan as well, whenever i sail to a particular sea area. I always thought it was due to someone's powerful radar that pings me. After i changed to SPX-5 and sacked Mr.Ivan, I've no problem. I'm very sure mine wasn't due to power supply issue.

Bill Roosa · Sep 2, 2013

What we have here is a failure to pass current.
If you are only seeing 12 volts with no load then you surely will see lots less once you power on the appliances. Goes away with the engine on due to the alternator boosting voltage to 14.4.
To check test the voltage at the term block with all the normal things running. I'm thinking that when the auto pilot commands the motor to turn on to make a course correction it causes a large(ish for the circuit) inrush current and the voltage goes low enough to make the control head electronics reset.

nautikal · Sep 2, 2013

I have discovered it is a good idea to disengage the Autopilot if using either my HF or VHF radio to talk or the boat will also do a "Crazy Ivan" I shall instal RF filters in the power line this winter. I have been told this is not an uncommon complaint.

Bill Roosa · Sep 2, 2013

hey hautikal
it is not about filtering the supply, it is about the voltage drop due to the VHF or HF radio (anything really) sucking current and the rest of the circuit seeing a voltage drop.
The only solution is larger wires and clean connections

jviss · Sep 2, 2013

Bill Roosa said:
Goes away with the engine on due to the alternator boosting voltage to 14.4.

A nit, but the voltage at the panel won't necessarily be 14.4, i.e., the acceptance charge voltage, because it will depend on the state of charge of the bank, the size of the bank, and what kind of regulator is installed. Could be much less than that during bulk, or nominally less during float.

That said, voltage droop with load can certainly be the result of inadequate wiring, but it can also be due to batteries that are not in top shape; the internal resistance of the batteries increases with age and mistreatment, and can become large enough so that with 12V no load, the voltage droops to below the equipment reset level when the steering motor kicks in.

One way to potentially fix this would be to put a huge capacitor across the motor wires - maybe a supercap. Just thinking out loud though, haven't given it a lot of thought.

(It's unfortunate that equipment designers don't consider this. I've experienced low voltage alarms from my Furuno GP32 gps receiver with a new house bank at 60-something percent state of charge. Would be better if they would design for something like 10 to 17 Volts for a nominally 12V system, to cover the low state of charge case, and the equalization charge case).

Skipper · Sep 3, 2013

"It's not the volts, it's the amps that will kill you". -Billy Crystal in "Running Scared"

I would look closely at the wire gauge used to power the terminal block. It may be too small to carry the load for all the gear attached, especially with radar.

With the alt running, it may have enough oomph to keep the juice up.

nolasafari · Sep 5, 2013

All of the above and clean all the connections, get some of my favorite contact cleaner DeoxIT by craig labs. This stuff is expensive but works.

I think Bill is correct about the radios, the frequencies are so far apart should be one or the other. Try with a Hand Held VHF on high power close to the unit. Filtering is still a good thing.

http://store.caig.com/s.nl/sc.2/category.188/.f

Jim

kloudie1 · Sep 5, 2013

Probably power connection.. Try 10 ga wire to the distribution block.. also check those itty- bitty spade connectors on the back of the control head. It is easy to miss the slot with the spade and the insulation will press the connection together pretty well but it has a pretty good voltage drop.. Make sure all of those little buggers are correctly connected..

jviss · Sep 5, 2013

More info, please

Mickey (the OP), are you still there?

A question: did it always do this, or is this a new thing, after having worked well for some time. Has anything else changed immediately before it began to malfunction? Was it "worked last season, not this season?"

Thanks,

jv