Raymarine EV1 - how sensitive to EM?

[RogerJolly]

My Evolution auto-pilot has started going mad, snaking virtually from 'lock to lock'. Been through the settings on the help line, but with no cure.

I've recently moved my Victron Orion B2B - now in a location just a few inches away from the EV1 bit. Wondering if it's that.

Manual says not to do such a thing. But then it's supposed to be three feet away from any electrical cables - not so realistic in a small boat, certainly not true of my installation, and it was working fine before the B2B relocation. (Guess the manufacturers are always going to tend towards strictness with their stipulations, to minimise chances of come-back.)

The course indication on the head looks fine.

Any insight gratefully received.

 

[fredrussell]

…recently moved my Victron Orion B2B - now in a location just a few inches away from the EV1 bit. Wondering if it's that.

Manual says not to do such a thing…

I think you’ve answered your own question there - or at least come up with the first possible cause in the list to be eliminated.

 

[jakew009]

With a bit of ingenuity it should be possible to get it 3’ away from everything. Mine is under one of the front v bed lockers.

 

[PaulRainbow]

Manual says don't do it, but you did it anyway.

Reason not to do it is because it's a sensitive electronic device.

 

[RogerJolly]

Didn't knowingly contravene the manual. Just in retrospect. If I was moving the EV1 rather than the B2B, it might have occurred to me at the time. Obvious now, but not so much when you're struggling in the heat of the job.

Just hoping for some insight into the situation from others' experience. Looks like the locker suggestion most likely.

I take manuals with a pinch of salt these days. Subject to error/spin/oversight like most things. On the phone the other day to Ambassador about their rope cutter - where's the indexing pip on the plastic 'bearing' like in the instructions, is it a manufacturing error? No, they say breezily, not had that for years - why don't you update the f'ing instructions then?

 

[kwb78]

The EV1 does seem to be quite sensitive to magnetic interference. We had to try a few different locations when installing to get the deviation to an acceptable level but it's been pretty solid ever since.

 

[Concerto]

A few years ago I had my EV1 start to do random things. I eventually solved the problem. Just watch this short video I made and you will realise how sensitive the EV1 truly is.

 

[PaulRainbow]

Raymarine fitting instructions could be better, all they say is ;

Location must be at least 1 m (3 ft.) away from any source
of magnetic interference, such as compasses and electrical
cables.

Garmin give better instructions ;

Testing a Location for Magnetic Interference
You can use a handheld compass to test a mounting location for
magnetic interference.
1 Hold a handheld compass in the CCU mounting location.
2 Move the compass six inches to the left of the location, then
six inches to the right, observe the needle, and select an
action:
• If the compass needle moves more than three degrees
during this step, magnetic interference is present. Select a
new mounting location and repeat the test.
• If the compass needle does not move, or moves less than
three degrees, proceed to the next step.
3 Repeat this process while moving the compass above and
below the mounting location.
4 Repeat this process while moving the compass in front of and
behind the mounting location.

 

[kwb78]

One thing you can do to check for obvious interference is use a metal detector app on your smart phone. They have a similar type of magnetometer used in the EV1 and you can get real-time feedback. It might not guarantee a location is ideal but would make it easier to rule out locations with obvious interference.

Here is an open source app that will do it or there are loads of others on the play store. I sure iPhones have similar available as well. Any app which will show the raw magnetometer data would work as well.

 

[fredrussell]

Raymarine fitting instructions could be better...

Very true. It took someone I know with an EV1 to explain to me how to get pilot steering to the wind. Hard over time still has me baffled. That said, it’s a great tillerpilot. Love mine.

 

[RogerJolly]

Thanks for inputs folks.

Seems focus is on compass deviations. Raymarine help line had similar focus when I last called them. We established the compass deviation was minimal and corresponded to the 'wet' compass. Problem is though that the boat over-steers wildly, swinging constantly 45 degrees port and starboard. I can't imagine this is down to some static compass swing problem. Couldn't get them to grasp it somehow.

I'm thinking it's more a problem is with the speed input - AP thinks we're hardly moving so has to do big swings to get a course change. Went through this on last call but one though, but this was out on the Solent, so a bit frantic and details are hazy now. We want through setting 'over the ground' (SOG) from GPS as the speed input as the speed log's bust (so no speed through water). (It puzzles me there's a 'Speed' option in the 'Data Sources' menu, and 'Vessel Settings'. If I understood it once I've forgotten now - you have to do some internet searching to get to these kinds of details, which should be just in the manual.) It's all a bit messy and confusing.

I'll go through it all again next time I'm on boat. Could well be I've still made some silly mistake with the setup (usually the case).

Failing that, will start to look at moving the EV-1. I did mention the B2B relocation to Raymarine on the last call, so obviously they suggested moving it.

What happens if all fails? Do I rip out the whole system and send it to Raymarine for checking? All this tech is fine but so complex it's scary when it goes wrong - do you end up with £1000's worth of useless electronics boxes?

Saw mention somewhere of recording some kind of log on SD card and sending it in to Raymarine for analysis. Raymarine UK support had no knowlege of such a thing though. I've been taling to 'Tier 2' (I think), maybe I need to speak to 'Tier 3' if there is one!

 

[sawduster]

We have a wiggle in the autopilot which I thought was EV1 related but after I went through a similar process to you to eliminate compass problems it remained. I took time to study the motion of the ram under the deck. There is a tiny bit of play in the ram shaft and the ram mountings - no more than a few mm but because the quadrant mounting is comparatively short compared to the radius of the wheel, what is a few mm over overshoot and compensation under the deck results in the wheel yo-yoing by almost 90 degrees.

 

[MattS]

@RogerJolly Just trying to think of other things that could be causing this (and I'm sure you've ruled these out):

- Is the damping setting on the autopilot set too low? Damping too low could mean the autopilot is just being too aggressive in its adjustments, which is very dependent on sensitivity of your own rudder / steering setup.

- Do you have any other compass / heading data sources on your network? Is it possible that the autopilot is configured to use a different heading source to the EV1 for some reason?

- Have you watched closely what is happening to the heading / compass reading during the times that it is steering erratically? Can you see any significant jumps in heading? If the autopilot is responding to an inaccurate heading you would expect that the heading value is not changing smoothly as the boat turns. Could you compare it with the ship's compass to see if they largely agree when the boat is turning?

- Depending on which Victron B2B you have, there have certainly been complaints of electromagnetic interference from those devices - they can also cause issues with VHF interference if placed too near to antenna cables etc. Personally, I would be avoiding the B2B being anywhere near the compass - even if you don't think this is causing the current issue - because EMF doesn't always appear consistently, and you don't want to find out that the B2B is in fact a problem at an inconvenient time...

Good luck - these things are infuriating to diagnose!

 

[PaulRainbow]

OP says

My Evolution auto-pilot has started going mad, snaking virtually from 'lock to lock'. Been through the settings on the help line, but with no cure.

I've recently moved my Victron Orion B2B - now in a location just a few inches away from the EV1 bit. Wondering if it's that.

Manual says not to do such a thing. But then it's supposed to be three feet away from any electrical cables - not so realistic in a small boat, certainly not true of my installation, and it was working fine before the B2B relocation. (Guess the manufacturers are always going to tend towards strictness with their stipulations, to minimise chances of come-back.)

The course indication on the head looks fine.

Any insight gratefully received.

A few clues highlighted above !

An extra clue "I did mention the B2B relocation to Raymarine on the last call, so obviously they suggested moving it."

"(Guess the manufacturers are always going to tend towards strictness with their stipulations, to minimise chances of come-back.)" NO, they tell you how/where to fit it so it works, if you ignore that, chances are it won't work.

Heading sensors are very sensitive to interference. Something as simple as leaving a screwdriver near one will play havoc with it. I've seen it where the sensor has been fitted under a seat and someone sitting on the seat with a phone in their pocket causes issues.

Remove the B2B and see if it cures the problem (you might need to go through setup sequence again to be sure). If it sure it, relocate the B2B.