Author Topic: ecu rf interference?  (Read 7140 times)

Online rodekyll

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ecu rf interference?
« on: February 11, 2015, 09:31:36 PM »
I'm laying out the goodies that will go in the traditional fuel tank on the trike.  The tank is being converted into a combination fuse box and glove box.

In the fuse box area, along with the actual fuse and relay blocks, will be the ecu, coils, turn relay, battery cutout, and perhaps HID power supplies and the airhorn compressor.

My question is -- Can I get rf or 'lectrical interference with the ecu by locating any of the other stuff mentioned too close to it?

Offline Wayne Orwig

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Re: ecu rf interference?
« Reply #1 on: February 11, 2015, 09:41:42 PM »
YES.

The HID power supply in particular generates a HUGE amount of radiated emissions. I had a couple of different electronic clock/thermometers on my EV that didn't really get anyway near the HID power, but they would occasionally get scrambled. I added a choke and cap to the power to the clock.

Yes, the problem was the HID power pack for sure. I don't know if it was interference on the 12 volt line, or radiating from the high voltage output. I suspect it was on the 12 volts, since filtering the 12 volts to the clock fixed it. The HID power was directly from the battery.

I would put the HID power pack on another planet. Isolate it as well as you can.
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Offline Sasquatch Jim

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Re: ecu rf interference?
« Reply #2 on: February 12, 2015, 12:37:31 AM »
  I just hate it when PFM can mess up your bike.
  Luddite that I am I prefer carbs and less electronics on my bikes.
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Online rodekyll

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Re: ecu rf interference?
« Reply #3 on: February 12, 2015, 03:18:10 AM »
This thing has more electronics on it than some oldsmobiles.

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Re: ecu rf interference?
« Reply #3 on: February 12, 2015, 03:18:10 AM »

Orange Guzzi

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Re: ecu rf interference?
« Reply #4 on: February 12, 2015, 09:04:10 AM »
May, might and could are all words to instill doubt and emotion.  I have "never" heard of an actual case of RF causing ignition problems. Sure I have heard static from spark plugs in a speaker, but that is the extent.   If there are such cases can some one please reference them.   Just like the sign at the construction sight that said "turn off all electronics, blasting ahead", I have never heard of a premature explosions from failure to turn off electronics.  Being an American, I like to see explosions and take it as a sign to turn on every radio in my vehicle. 

Offline Wayne Orwig

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Re: ecu rf interference?
« Reply #5 on: February 12, 2015, 09:33:38 AM »
May, might and could are all words to instill doubt and emotion.  I have "never" heard of an actual case of RF causing ignition problems. Sure I have heard static from spark plugs in a speaker, but that is the extent.   If there are such cases can some one please reference them.   Just like the sign at the construction sight that said "turn off all electronics, blasting ahead", I have never heard of a premature explosions from failure to turn off electronics.  Being an American, I like to see explosions and take it as a sign to turn on every radio in my vehicle. 

Actually, I see it often.
One of my jobs is to place products in an RF chamber and bombard it with RF radiation. The most sensitive products are for cable TV. It is hard to make those immune to interference in the same band. But I can reboot, or at least shut down computers. And I have seen motorized equipment turn itself on because of RFI. Not a real safe thing.
You can be sure, at some level, the radiated or conducted RF from something like the HID power supply can get into and disrupt the ECU. And I would imagine that the timing sensor input has the least amount of filtering on it, so it is likely the most susceptible.
So there is nothing wrong with following good design practices to try to prevent future problems.


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Online rodekyll

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Re: ecu rf interference?
« Reply #6 on: February 12, 2015, 02:52:47 PM »

May, might and could are all words to instill doubt and emotion.  I have "never" heard of an actual case of RF causing ignition problems. Sure I have heard static from spark plugs in a speaker, but that is the extent.   If there are such cases can some one please reference them.   Just like the sign at the construction sight that said "turn off all electronics, blasting ahead", I have never heard of a premature explosions from failure to turn off electronics.  Being an American, I like to see explosions and take it as a sign to turn on every radio in my vehicle. 

First, if you can't comprehend the question, don't challenge it.  I didn't ask about the effect of interference on ignition.  I asked about the effect of interference on the ecu.

Second, 'might' and 'could' also start 'research' and 'understanding'.  It depends on if you're a brain half-full or brain half-empty kinda guy. 

It's because I haven't heard of it in this environment that I'm asking the question.  I'm not a lawyer.  I often ask questions I don't already know the answer to.  I seem to learn more that way.  In my opinion it's a better approach than what's being called here the "American Way" of keying up the CB at an active demo site to see if the blast warnings are true.  Do you also pour McDonald's coffee in your lap to see if the "CAUTION: HOT" warning is true?

You're asking for references of 'cases' where this has happened.  If I knew of any specifically involving the components I listed on a motorcycle, I wouldn't be asking about it here.  However, radio and electrical interference is such a universally recognized issue that the FCC has made rules to limit the amount of interference in what they call class A, B, C consumer and industrial devices.  There is even an FCC ID database that assigns a unique "serial number" to every electronic component in a piece of equipment, and then to the assembly, so if a part or assembly is found to be in violation of the rules, it can be identified and pulled from the world supply -- or at least blacklisted from the US market.

A LOT of equipment, including computers, microwaves, security systems, and even vacuum cleaners, are often still stickered as interference generators.  The IEEE and ANSI also contribute rules for residential and industrial/commercial building codes governing the placement of high voltage/low voltage/data cable and equipment.  When doing structure planning and cabling/equipment installation I've got more rules to follow than I can keep track of.  So they generously supply me with rule books, auditors, and inspectors to school me on my transgressions.

In the marine environment, you've got radios, radars, sounders, AIS transceivers, gensets, GPS, alternators, computers, plotters, inverters, and goddess knows what all else competing for space and what we call an 'operating envelope' in a very small area.  If you don't keep all those components in separate envelopes, properly installed, nothing works.  If the boat is not properly grounded, nothing works.  If the passive interference from trolling wire rubbing against the water isn't properly attenuated, nothing works.  A simple mistake like running the vhf antenna wire improperly can put all the navionics on tilt.  I just got me a nib Furuno Radar for the RAGING FERRET.  It's got an entire section in the manual telling me how far from this and that I need to have the twirley, where the head can be, and how not to route the cabling between them.  The warnings clearly state that navionics and compass could, should, would be affected by improper installation.

My reasoning is that if simple , passive line noise can impact a computer network -- a situation I see frequently -- and from simple things like putting a network router too close to an old-school oil furnace or connecting it to the same circuit as the fluorescent lights -- it seems reasonable that an active noise generator, like a coil or HID converter could do the same on the trike, and possibly from a greater distance.  I know that some WG members work at this level in real life, and that some of these same folks have installed noise generators on their bikes and cars.  So WG seemed like a good place to ask the question.  Wayne's experience may have saved me a crap-ton of grief.  And like he says, it's better to find that out during the design stage than on the road test.

So thanks, Wayne.   :)

Offline Wayne Orwig

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Re: ecu rf interference?
« Reply #7 on: February 12, 2015, 06:11:59 PM »
In the marine environment, you've got radios, radars, sounders, AIS transceivers, gensets, GPS, alternators, computers, plotters, inverters, and goddess knows what all else competing for space and what we call an 'operating envelope' in a very small area.  If you don't keep all those components in separate envelopes, properly installed, nothing works.  If the boat is not properly grounded, nothing works.  If the passive interference from trolling wire rubbing against the water isn't properly attenuated, nothing works.  A simple mistake like running the vhf antenna wire improperly can put all the navionics on tilt.  I just got me a nib Furuno Radar for the RAGING FERRET.  It's got an entire section in the manual telling me how far from this and that I need to have the twirley, where the head can be, and how not to route the cabling between them.  The warnings clearly state that navionics and compass could, should, would be affected by improper installation.

I've spent time testing to EN 60945, for marine use. Equipment for marine use basically is not allow to radiate ANYTHING in the 156 to 165MHz range. VHF radio. It can be a problem.

Anyway, isolate the HID power well. Maybe leave room for a future choke on the HID power line if needed. Keep the timing sensor line clean (is it shielded?). I don't think you'll have any problems beyond that.
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Re: ecu rf interference?
« Reply #8 on: February 12, 2015, 06:32:13 PM »
I can shield the timing sensor cable with a braided sleeve.

Will a ferrite bead act as choke enough?



Offline Wayne Orwig

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Re: ecu rf interference?
« Reply #9 on: February 12, 2015, 07:19:47 PM »
I can shield the timing sensor cable with a braided sleeve.

Will a ferrite bead act as choke enough?

If you have trouble and have access to a snap on one, so you can get a few turns through it, you could try that. That is actually how I fixed my clock. I medium sized ferrite bead with three of four turns of the power wire through it.
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Re: ecu rf interference?
« Reply #10 on: February 12, 2015, 07:52:08 PM »
I have snap-ons and full roundies in sizes up to fitting my little finger through.  Since they're completely passive, I'll install them as I set up the converters.  Much easier to do on the bench.  When I have a round one I can't feed the plug through, I just pull a loop of the wires through,  wrap, and zip tie the apex.  Do you have a problem with that shortcut, or should I use snap-ons.  Snap-ons take a LOT of wire length to get four wraps on. I'd prefer to not use them.

You say the power wires.  Just to clarify -- The wires inbound to the converter or outbound to the bulb?

Offline Wayne Orwig

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Re: ecu rf interference?
« Reply #11 on: February 12, 2015, 08:03:49 PM »
You say the power wires.  Just to clarify -- The wires inbound to the converter or outbound to the bulb?

The problem I saw appeared to be related to the 12 volt side.
Snap on beads aren't really as good as full molded ones, but more turns is very good it you can. I'm sure you'll be good, just keep that HID supply and the lines away from everything.
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Re: ecu rf interference?
« Reply #12 on: February 12, 2015, 08:10:53 PM »
Thanks for the timely replies, Wayne.  I'm head off to the shop to do this chore now.   :)

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Re: ecu rf interference?
« Reply #13 on: February 13, 2015, 09:59:45 AM »
First, if you can't comprehend the question, don't challenge it.  I didn't ask about the effect of interference on ignition.  I asked about the effect of interference on the ecu.

Second, 'might' and 'could' also start 'research' and 'understanding'.  It depends on if you're a brain half-full or brain half-empty kinda guy. 

It's because I haven't heard of it in this environment that I'm asking the question.  I'm not a lawyer.  I often ask questions I don't already know the answer to.  I seem to learn more that way.  In my opinion it's a better approach than what's being called here the "American Way" of keying up the CB at an active demo site to see if the blast warnings are true.  Do you also pour McDonald's coffee in your lap to see if the "CAUTION: HOT" warning is true?

You're asking for references of 'cases' where this has happened.  If I knew of any specifically involving the components I listed on a motorcycle, I wouldn't be asking about it here.  However, radio and electrical interference is such a universally recognized issue that the FCC has made rules to limit the amount of interference in what they call class A, B, C consumer and industrial devices.  There is even an FCC ID database that assigns a unique "serial number" to every electronic component in a piece of equipment, and then to the assembly, so if a part or assembly is found to be in violation of the rules, it can be identified and pulled from the world supply -- or at least blacklisted from the US market.

A LOT of equipment, including computers, microwaves, security systems, and even vacuum cleaners, are often still stickered as interference generators.  The IEEE and ANSI also contribute rules for residential and industrial/commercial building codes governing the placement of high voltage/low voltage/data cable and equipment.  When doing structure planning and cabling/equipment installation I've got more rules to follow than I can keep track of.  So they generously supply me with rule books, auditors, and inspectors to school me on my transgressions.

In the marine environment, you've got radios, radars, sounders, AIS transceivers, gensets, GPS, alternators, computers, plotters, inverters, and goddess knows what all else competing for space and what we call an 'operating envelope' in a very small area.  If you don't keep all those components in separate envelopes, properly installed, nothing works.  If the boat is not properly grounded, nothing works.  If the passive interference from trolling wire rubbing against the water isn't properly attenuated, nothing works.  A simple mistake like running the vhf antenna wire improperly can put all the navionics on tilt.  I just got me a nib Furuno Radar for the RAGING FERRET.  It's got an entire section in the manual telling me how far from this and that I need to have the twirley, where the head can be, and how not to route the cabling between them.  The warnings clearly state that navionics and compass could, should, would be affected by improper installation.

My reasoning is that if simple , passive line noise can impact a computer network -- a situation I see frequently -- and from simple things like putting a network router too close to an old-school oil furnace or connecting it to the same circuit as the fluorescent lights -- it seems reasonable that an active noise generator, like a coil or HID converter could do the same on the trike, and possibly from a greater distance.  I know that some WG members work at this level in real life, and that some of these same folks have installed noise generators on their bikes and cars.  So WG seemed like a good place to ask the question.  Wayne's experience may have saved me a crap-ton of grief.  And like he says, it's better to find that out during the design stage than on the road test.

So thanks, Wayne.   :)

So, how does adding a third wheel to a motorcycle change the RMI is your question?  I comprehended the question and have never seen a situation where the placement of coils affected the performance of the electronics.  Most motorcycles have a limited amount of locations to mount the multitude of parts due to the size.  The general location of all the electronics are within 2 feet or less.  On my Tonti framed bike the coils and ICU are within 18 inches, on my Buell, less the 12 inches.  No expert in the field of RFI, but seat of the pants experience seems to indicate that on a motorcycle, it is not real important.  On a boat, in the cold and outside the view of land, maybe much more so.  Then again, I would like to see some real evidence of failures and not just textbook data.  Just like keying the cb mike at a blasting zone.  See the signs, but have never read the headlines.

Offline pressureangle

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Re: ecu rf interference?
« Reply #14 on: February 13, 2015, 10:15:04 AM »
May, might and could are all words to instill doubt and emotion.  I have "never" heard of an actual case of RF causing ignition problems. Sure I have heard static from spark plugs in a speaker, but that is the extent.   If there are such cases can some one please reference them.   Just like the sign at the construction sight that said "turn off all electronics, blasting ahead", I have never heard of a premature explosions from failure to turn off electronics.  Being an American, I like to see explosions and take it as a sign to turn on every radio in my vehicle. 

Back in Racing days, 883 Sportsters were notorious for losing the ignition module at about 5000 rpm if you used non-resistor plugs and plug wires. Just for reference.
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Re: ecu rf interference?
« Reply #15 on: February 13, 2015, 10:18:37 AM »
So it's the HID power supply you need to be aware of, that makes sense, high frequency switching.

I recently worked on a prototype liquid storage battery that had a bi-directional inverter, the manufacturer described it as "A radio station in a box" sure enough when that was started it blanked out all the instrumentation within 100 feet.

Perhaps Wayne you could do a tutorial on how to install the HID power supplys
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Offline Wayne Orwig

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Re: ecu rf interference?
« Reply #16 on: February 13, 2015, 10:34:34 AM »
No expert in the field of RFI, but seat of the pants experience seems to indicate that on a motorcycle, it is not real important.  

I don't do a lot of testing, but I was convinced that getting the spark plug wires out of the bundle with the timing sensor reduced the idle still hiccups on my Centauro.

And a bad spark plug cap on a Stelvio can scramble the dashboard. This has happened to many people.
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« Last Edit: February 13, 2015, 10:39:43 AM by Wayne Orwig »
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Re: ecu rf interference?
« Reply #17 on: February 13, 2015, 11:12:48 AM »
Mike , you still ride too fast  ;D

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Re: ecu rf interference?
« Reply #18 on: February 13, 2015, 02:34:45 PM »
Interesting thread for it's technical shares. I work with outfits that make computers for the military, and I see these tactics utilized in them all the time.

Barely relevant, as an auto mechanic in the eighties, I had a customer who was driving a high end Mercedes that belonged to a friend while the person was out of town. The car had a remote starter that could be activated from the key fob, pretty jazzy for it's day.

He said while he was driving through Mission Valley on the freeway the starter engaged and ground the flywheel for a mile or so. We checked the system out and found nothing evident so he went on his way.

Saw him again the next day. He said that on his way home it happened again - IN THE SAME PLACE ON THE SAME FREEWAY.

We connected the dots and disconnected the system.
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Offline Moto Fugazzi

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Re: ecu rf interference?
« Reply #19 on: February 13, 2015, 06:53:51 PM »
I have a similar situation with a LED controller from ADVMonster http://stores.advmonster.com/waterproof-wireless-led-dimmer-with-high-beam-bypass/
This unit lets me have the LED Aux. lights on at a predetermined level, and when I turn on the high beam, the LED's go full blast. I've noticed when I use this feature, the AFR jumps up on my V11S from 13.5 to 14.0 or higher and the bike runs too lean (IMO). If I remove the high beam bypass from the circuit, my bike doesn't change AFR whether the LED's are still set at the predetermined level, or I turn the LEDs on at full blast.

Here's a quote from a gent on the V11 forum about LED signal:

"Think,with your LEDs "on" you have overload on the alternator. Unfortunately most LED-Beams have internal switching power supplies with constant current regulation which produce hard currentspikes in motos electrical system. Your "Module" (it's a pulse width modulation) does the rest. The currentspikes bring your alternator into magnetical saturation and the voltage breaks down in common mode with the spikes. The regulator also can't handle the spikes (10 kHz....1MHz).
 
Would be a good idea buffering the Module primaryly with a diode and an electrolytic with an foil condensator in parallel to damp the pulses.
 
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The thread is here, if want to access it. http://www.v11lemans.com/forums/index.php?showtopic=18674&hl=%2Brunning+%2Blean
Ken
« Last Edit: February 13, 2015, 06:55:19 PM by Moto Fugazzi »
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Offline Wayne Orwig

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Re: ecu rf interference?
« Reply #20 on: February 13, 2015, 07:20:23 PM »
I have a similar situation with a LED controller from ADVMonster http://stores.advmonster.com/waterproof-wireless-led-dimmer-with-high-beam-bypass/
This unit lets me have the LED Aux. lights on at a predetermined level, and when I turn on the high beam, the LED's go full blast. I've noticed when I use this feature, the AFR jumps up on my V11S from 13.5 to 14.0 or higher and the bike runs too lean (IMO). If I remove the high beam bypass from the circuit, my bike doesn't change AFR whether the LED's are still set at the predetermined level, or I turn the LEDs on at full blast.

Here's a quote from a gent on the V11 forum about LED signal:

"Think,with your LEDs "on" you have overload on the alternator. Unfortunately most LED-Beams have internal switching power supplies with constant current regulation which produce hard currentspikes in motos electrical system. Your "Module" (it's a pulse width modulation) does the rest. The currentspikes bring your alternator into magnetical saturation and the voltage breaks down in common mode with the spikes. The regulator also can't handle the spikes (10 kHz....1MHz).
 
Would be a good idea buffering the Module primaryly with a diode and an electrolytic with an foil condensator in parallel to damp the pulses.

I don't have that issue. I designed my own LED dimmer.  ;D

It may be a bit tough figuring out WHAT is causing it. The LEDs has switch mode regulators which can do it, and of course the dimmer is a noisy PWM. So the LED driver may be the issue, or the PWM may be it. BUT, since it only happens with the high beam feature, I would start by filtering that high beam switch line. Maybe it is coupling noise into the headlight wiring, and on into the main harness.

Since I have an unlimited supply of large ferrite beads, I would start adding ferrites to that line or the power lines. The more turns you can get the better on the beads.  Also, make sure that the LED lines are not near the ECU sensor lines. Something like a LED power cable running parallel for a distance along the cable with the TPS, or a temperature sensor, could be an issue.

The 'overloading the alternator' comment doesn't make a lot of sense.
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Re: ecu rf interference?
« Reply #21 on: February 13, 2015, 08:32:07 PM »
I also disagree that a 30w LED is overloading an alternator that used to do a 55w halogen.  The math goes the other way. 

The scope readout is vaguely reminiscent of a modified sine wave, such as you'd see in a cheap inverter.  The pattern could be modifying the DC waveform, causing the ecu to mis-time or change the duration of the injector pulse. 

In the marine environment (where I most often see this), it not only affects other devices using the same battery/charging universe, it also affects things like computers and navionics that are directly plugged into it.  there is no cure for a high watt inverter other than to replace it with a proper waveforming inverter.  The noise we see in the scope print isn't as much as with an inverter, so I'd at least try choking the power lines and giving them good separation (as Wayne already suggested) before getting too excited about the problem.  Although it seems silly, a tin foil hat around the noisy wires also reduces bleed.

We get awful bleedover from POTS (telephone) cabling when a noisy line is in the same bundle as Cat5 (network cable).  We can sometimes run shielded twisted pair to attenuate some of it, but shielding also sucks the signal out of the cat5, so it can only be run short distances.

I think there's some good information coming out of this topic, so I'll let it run.  The LED interference is something I had not considered, but my LED headlamp is a sealed unit -- nothing but wires come out of it.

My project moved past the location decisions last night, so I've picked my poison.  I have a small area to put all the stuff into -- the front half of a loop tank.  So getting the components 'feet' away from themselves isn't possible.  My other issue is airflow in the confined space, so some placement was made with a nod toward cooling the power supplies and ecu.  I did manage to get the ecu way up in the front of the electrics bay, and the converters on the back side of the partition that separates the electrics from the glove box, which uses the back portion of the tank.

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Re: ecu rf interference?
« Reply #22 on: February 13, 2015, 11:55:25 PM »
I also disagree that a 30w LED is overloading an alternator that used to do a 55w halogen.  The math goes the other way. 

The scope readout is vaguely reminiscent of a modified sine wave, such as you'd see in a cheap inverter.  The pattern could be modifying the DC waveform, causing the ecu to mis-time or change the duration of the injector pulse. 

In the marine environment (where I most often see this), it not only affects other devices using the same battery/charging universe, it also affects things like computers and navionics that are directly plugged into it.  there is no cure for a high watt inverter other than to replace it with a proper waveforming inverter.  The noise we see in the scope print isn't as much as with an inverter, so I'd at least try choking the power lines and giving them good separation (as Wayne already suggested) before getting too excited about the problem.  Although it seems silly, a tin foil hat around the noisy wires also reduces bleed.

We get awful bleedover from POTS (telephone) cabling when a noisy line is in the same bundle as Cat5 (network cable).  We can sometimes run shielded twisted pair to attenuate some of it, but shielding also sucks the signal out of the cat5, so it can only be run short distances.

I think there's some good information coming out of this topic, so I'll let it run.  The LED interference is something I had not considered, but my LED headlamp is a sealed unit -- nothing but wires come out of it.

My project moved past the location decisions last night, so I've picked my poison.  I have a small area to put all the stuff into -- the front half of a loop tank.  So getting the components 'feet' away from themselves isn't possible.  My other issue is airflow in the confined space, so some placement was made with a nod toward cooling the power supplies and ecu.  I did manage to get the ecu way up in the front of the electrics bay, and the converters on the back side of the partition that separates the electrics from the glove box, which uses the back portion of the tank.

My previous comment regarding rfi in motorcycles and not ever having experienced it has solicited various responds.  Which I find interesting, even though I have limited experience in the finer points of electronics.  Your description above seems to discuss two separate issues, one the current thru the wire and two, the hall effect of the current thru the wire.  I would assume that the hall effect (RFI) of the current thru the wire is what one should look for in locating instruments and an inverter is required for clean current to an electrical instrument?  Would a mechanical voltage regulator effect the operation of an electronic control as well? 

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Re: ecu rf interference?
« Reply #23 on: February 14, 2015, 12:30:29 AM »
We look for both.  Something I use for rf is the receiver for a telephone line ringout tester.  It will sound static and get 'hotter' or 'colder' as you look for the sweet spots.

No, the inverter is simply to take the battery 12/24/48vDC to shore power AC.  Many boats run both.  Appliances, light bulbs, refrigeration, etc don't care too much about the AC waveform, but instruments and computers do.

In theory we're always running off battery when running DC.  On the boats we often have redundant and multiple batteries, some of which would not fit in a radio flyer wagon, and would probably crush it if you could.  It's a lot of ballast to settle down the pulses of a voltage regulator.  In practice they're noisier than a murder of crows.  Gensets are worse.  I suspect a lot of it has to do with poor grounding and a lack of capacitors on the noise generators. 


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