Wire Gauge for Ground Plane?

I can't imagine the wire gauge matters at all, I'd use a fine wire simply because it's cheaper and easier to hide. Different gauges of wire wouldn't matter at all, the wavelength is hundreds of feet for the TMCC signal.

quote:

Originally posted by gunrunnerjohn:
I can't imagine the wire gauge matters at all, I'd use a fine wire simply because it's cheaper and easier to hide. Different gauges of wire wouldn't matter at all, the wavelength is hundreds of feet for the TMCC signal.

Hundreds of feet???????????

What is the full wavelength????
David

I use AL heating and air conditioning tape next to the track and connect it with the ground wire attached to a metal water pipe using a screw. I place ballast and ground cover over the tape and it becomes hidden. This works for me.

Thanks, gunrunnerjohn and trains41.

RE: the aluminum tape, I wish I'd thought of it when I was laying track several years ago. How did you attach it to the ground wire?

Whoever answers Bob's question, there are a couple more I'd love to know the answers to also - what do you do if no water pipes handy, and how do you measure the radio signal strength (besides whether the trains work or not).

quote:

Originally posted by Ginsaw:
what do you do if no water pipes handy, and how do you measure the radio signal strength (besides whether the trains work or not).

You can tie the ground wire to the ground of your electrical system. I have my ground wire connected to the ground or center prong of a regular 110 AC plug. The negative and positive, or silver and copper, prongs have nothing wired to them. They are kept only for mechanical support. You can also place a power diode in line with your ground wire so as to block any possible back feed, silver ban pointed away from the prong. Plug this into any 110 AC wall outlet. I really do not feel the diode is needed but I read that is a good safty feature.

As for testing your signal strength the only practical way to do that is with the DCS system. You also need a 2.0 or 3.0 MTH engine running in signal mode. A ten being a perfect signal and anything above a five or six being acceptable.
As far as I know for the Lionel system you will have to use a power meter tuned to their carrier, this can get expensive and tricky.

What I would do is to hop over to the TMCC pages and ask them. I'm sure there must be a better way, I just don't know of any.

This is a link to web site about using TMCC for outdoors (aka garden) layouts. There is some discussion of the ground plane in the "Earth Ground Requirements" section:

Using TMCC Outside

I think the wavelength IS in the hundreds of feet. I think the freq is 455 hz.

quote:

I think the wavelength IS in the hundreds of feet. I think the freq is 455 hz.

full wave, 2162 feet.

About the testing of the signal question, assuming the signal strength can be tested, would that testing give you a value or figure for your ground plane to show its effectiveness? Or is the signal strength a figure that doesn't separate out anything for the ground plane? In other words I'd like to test the ground plane.

And on the outlet thing, my layout is in an add-on upstairs bedroom. The plug used goes into a wall box behind which is not an attic, but more of a large crawl space. When I did the trainroom wiring I had an electrician put in an exhaust fan back there and run a couple light fixtures so I could use the space for train storage.

Anyway, I was aware from reading here about the need for ground planes, although I admit to not totally understanding them. So, I asked him to check that wall box and see if it was properly grounded. The center prong does not go anywhere, and I recall he said it would be difficult to connect it up to any water pipes or to the outside ground pole. I think he added a device to the box itself which he said would help a little. Unfortunately I don't know now what that was.

The point of all which is, I have with some trains possible reception problems and not so with others, and am just trying to understand fully this issue and to get to the bottom of whether my ground plane has a problem, or on the other hand if I just have bad engine boards to start with.

quote:

Originally posted by Ginsaw:
About the testing of the signal question, assuming the signal strength can be tested, would that testing give you a value or figure for your ground plane to show its effectiveness? Or is the signal strength a figure that doesn't separate out anything for the ground plane? In other words I'd like to test the ground plane.

And on the outlet thing, my layout is in an add-on upstairs bedroom. The plug used goes into a wall box behind which is not an attic, but more of a large crawl space. When I did the trainroom wiring I had an electrician put in an exhaust fan back there and run a couple light fixtures so I could use the space for train storage.

Anyway, I was aware from reading here about the need for ground planes, although I admit to not totally understanding them. So, I asked him to check that wall box and see if it was properly grounded. The center prong does not go anywhere, and I recall he said it would be difficult to connect it up to any water pipes or to the outside ground pole. I think he added a device to the box itself which he said would help a little. Unfortunately I don't know now what that was.

The point of all which is, I have with some trains possible reception problems and not so with others, and am just trying to understand fully this issue and to get to the bottom of whether my ground plane has a problem, or on the other hand if I just have bad engine boards to start with.

If the outlet that the command base is plugged into has no ground this is a likely source of your signal issue. Unless I misunderstood previous threads on this, Lionel tmcc/legacy trainsmits the signal through the ground prong on the base plug through your home wiring.An incorrectly wired home results in potential signal issues.Bases plugged into bad power strips instead of the wall have caused signal issues as well. A primitive but effective method of checking for signal issues is to hold your hand just over the problematic loco and see if it responds normally,if so you have signal /ground plane issues. Remember to be sure your track, wheels and pickup rollers are clean. Dirty track etc,can make locos act strange too.

quote:

If the outlet that the command base is plugged into has no ground this is a likely source of your signal issue.

It doesn't. But the funny thing is, some engines have problems, others don't. My steamers for instance seem good with the current setup.

I've tried holding my hand over engines and to my knowledge it's proved nothing.

The signal goes thru the New ZW commons and to only one outside rail, not both. And the base is plugged into its own power strip. I turn it on before I turn on track power which is plugged into a separate strip. As far as I can tell, both strips are fine. Both strips are plugged into that same wall box. I've tried plugging them other ways and using two separate wall boxes and tried it without the power strips, but it doesn't seem to make things run better.

The kinds of problems I'm talking about include stuff like out-of-the-blue run-away situations (which can be alarming) and ignoring further commands while an engine is running and way too much turning of the BRK being needed to get any reaction.

..at times I think I just must have a haunted road..

If you don't have access to "earth" ground via the house wiring you can create a ground plane. Normally you connect the three prong wall wart directly to the outlet. If you install a "cheater" between the wall wart and the outlet, you can use the grounding lug on the cheater as a tie point for your forced ground plane.

Attaching the ground wire to the AL tape is done by using a small screw securing a bare end of the ground wire to AL side of the tape. The screw is placed through the tape into the supporting wood top of the layout.

quote:

Originally posted by Ginsaw:

quote:

If the outlet that the command base is plugged into has no ground this is a likely source of your signal issue.

It doesn't. But the funny thing is, some engines have problems, others don't. My steamers for instance seem good with the current setup.

I've tried holding my hand over engines and to my knowledge it's proved nothing.

The signal goes thru the New ZW commons and to only one outside rail, not both. And the base is plugged into its own power strip. I turn it on before I turn on track power which is plugged into a separate strip. As far as I can tell, both strips are fine. Both strips are plugged into that same wall box. I've tried plugging them other ways and using two separate wall boxes and tried it without the power strips, but it doesn't seem to make things run better.

The kinds of problems I'm talking about include stuff like out-of-the-blue run-away situations (which can be alarming) and ignoring further commands while an engine is running and way too much turning of the BRK being needed to get any reaction.

..at times I think I just must have a haunted road..

Ground plane issues don't usually effect every loco on a particular layout,usually the ones with the weakest reception. Steamers have better antennas integrated into the handrails.

It's command base to wall wart, wart to computer strip, three prong strip plug to three hole wall box. But, that third hole isn't connected to anything off the box. Except whatever device, if any, the electrician added to the box.

So would there be any point to going to the trouble to install any wires on or under the layout for a ground plane in those circumstances?

Bob, sorry if this stretches your topic a bit.

Oh, one other thing. I've been told that when you have lack of signal, the engine just stops. That would tend to indicate that a run-away probably has some other cause??

quote:

So would there be any point to going to the trouble to install any wires on or under the layout for a ground plane in those circumstances?

You need a ground reference plane for TMCC to work. Either "Earth" ground or a ground plane you create using wiring/mesh off of the third prong. Since you don't have easy access to earth ground you will have to create a ground plane using the third prong.

quote:

I've been told that when you have lack of signal, the engine just stops. That would tend to indicate that a run-away probably has some other cause??

Not exactly. If the engine does not detect a command signal at start up it will come up in conventional mode. If there is a power bump for a loco that exceeds the reset time AND the engine comes back up and still doesn't see a command signal it will go into conventional and MAY take off at full throttle. that's a lot of if's and dependency on how the engine was configured to run in conventional mode (E-unit sequence) AND the possibility that other electrical events on the track that could be causing more problems (e.g. a dragging truck short). If there is a signal loss while operating in command mode the headlight starts to blink rapidly. If the loss is too long or too severe the engine stops.

quote:

Originally posted by chuck:

quote:

I think the wavelength IS in the hundreds of feet. I think the freq is 455 hz.

full wave, 2162 feet.

How did you arrive at 2162?

I believe the frequency is 455 Mhz.

To maximize the effectiveness of the ground strips(or radials) they should be a division of the total wave length ,meaning that they can be 1/2 , 1/8 or 1/16 or smaller if need be ,
but should never be random.This can do more harm than good

David

quote:

I believe the frequency is 455 Mhz.

It's 455 Khz. The CAB-1 to Command base is 27 Mhz.

What is a "dragging truck short"? A truck that's partially derailed? I don't have anything like that going on.

I'm not aware of any "power bumps" or engines coming up in conventional mode or flickering lights at all. Basically, one will keep on running seemingly normally until it runs away or starts ignoring commands.

What they are doing is, normal command ID recognition and start up and moving out and running round and round, and changing direction and all different speeds. Then maybe they will start not responding so well to BRK commands, or maybe you stop, then slowly back up to couple to a train and are backing, or maybe you're doing nothing but running straight ahead, and then, without regard to where you are on the layout, BAM - off to the races. When it happens trying to control it with the Cab-1 does nothing. The only way to stop such an engine is to use the New ZW handles and cut the current.

Anyhow, my electrician said it wasn't practical to connect the wall box/socket up to earth ground. We even went outside to find out where the pole was (it was imbedded deep in concrete on the side of the garage). And we looked for water pipes too. That could have been done, but not cheaply or easily.

But, if I understand right, I think I'm being told that it serves a purpose ground plane wise, for the three prong plug off the strip to be plugged into the three hole wall socket, EVEN THOUGH the third wall prong hole goes nowhere and isn't connected to anything in back of the wall.

That's the part I'm having trouble wrapping my mind around.

quote:

But, if I understand right, I think I'm being told that it serves a purpose ground plane wise, for the three prong plug off the strip to be plugged into the three hole wall socket, EVEN THOUGH the third wall prong hole goes nowhere and isn't connected to anything in back of the wall.

Without a ground plane the system will not work. If your house has "normal" wiring the third prong goes to earth ground. This makes it convenient to use with TMCC. If your house wiring doesn't tie to earth ground you use the third prong on the wall wart to establish a local ground plane. You attach your ground plane wire to this.

Easiest way to check for the signal is to hold your hand above the engine that is not responding. With your hand over the engine and you have a good signal the engine will respond to your commands. If it does not respond, then you have not signal to the track. I am talking TMCC only, I know nothing about MTH engines, that's my story and I am sticking to it.

Thanks to all for the interesting discussion. And I don't mind at all if the thread went beyond my original questions -- I found it all helpful.

Would one of y'all please confirm the following for me, to make absolutely sure I understand what I'm doing to create the ground plane:

Run a wire under the table following the track in its entirety.

The wire gauge doesn't matter.

The distance between the wire and the track above doesn't matter (at least not up to 6 inches).

If the track is a double mainline, the wire can run half way between the two tracks.

If the track is a loop, don't connect the ground plane wire into a loop as well -- leave one end unattached.

Connect one end of the wire to the screw in the wall outlet, as follows:



Chuck, am I understanding you correctly that a wall wart is needed?

And is it true that if holding a hand over the loco with the presumed TMCC signal reception problem does not fix it, then wiring a ground plane won't help?

Thanks.

Holding your hand over the loco improves a weak ground plane with your body acting as the improvement. This doesn't always work because different people have different electrical properties (remember the issues with the iPhone 4's "edge" antenna.

If you house does not have the third prong wired to earth ground you need to establish a secondary ground plane. Take a three prong to two prong adapter (called a cheater) to plug the wall wart into. You attach your ground plane wire to the lug on the cheater. The center screw on a wall plate cover SHOULD be connected to the ground terminal even if the backside isn't connected to anything. I KNOW the ground lug on the cheater is connected to the third prong and will work for establishing a ground plane.

Just thought it might help to know why I'm going to the trouble of wiring a ground plane.

I have a 20x16 FasTrack layout with TMCC that works flawlessly for all 15 locos except one: the newest addition, a Lionel CP F3 AA received last spring. The layout has been running for 5 years with no issues.



When the new loco is placed on the track and the layout powered up, its lights come on. However, there is no sound and no response to the BRK throttle. If I crank it 5-10 revolutions, the engine takes off very slowly. A few more revolutions and its speed inches up. Then all of a sudden, a slight movement of the know (15-20 degree rotation) makes it accelerate suddenly, but not runaway acceleration. Slowing it down requires many revolutions too.

None of the other TMCC locos behave like this on the layout.

When I put the problem loco on a 12x4 loop in another room also running TMCC, it works perfectly, none of the sluggish throttle response, and plenty of sound.

Return to the main layout, same problem. Go back to the test track, works fine.

The only other change that might be implicated in the problem is an LED control panel I built that went operational just before the difficulties with the loco. The panel is made of sheet aluminum.



Lionel Talk to Us has been exceptionally responsive and willing to help. They suggested I tie the aluminum panels to the ground plane wire, which I've done to no avail.

I just haven't fully completed the ground plane wiring yet (about half done now), but before proceeding I wanted to make sure I was on the right path.

Thanks in advance to all who've offered suggestions. Further comments are welcomed.

Thanks for clarifying, Chuck, I'll try the wall wart solution you suggested.

When you say the loco works fine on the "other" layout in the other room are you using a different command base? If so, the issue may be the base tuning frequency with respect to the engine acting up on the main layout.

Yes, I have an entirely separate command base and CAB-1 for the test track. The layout and test track are separated by 15 feet or so.

The loco has problems on the layout regardless of whether the test track's command base is on or off.

Chuck -

Is there any way to check that the wiring for ground plane is "correct"," e.g. with a multimeter, to verify that it's actually performing the intended function (aside from fixing the apparent signal reception problem).

I don't know of any way to "test" the ground plane other than the way it behaves.

If it's not too much trouble, swap your command bases to see if the issues with the one loco follows the command base or the layout.

Sure glad I run Pre/post war. This is too complicated.

Unless I have read this wrong, there is only one loco acting up.

If that is the case, then the problem lies with that one loco. You might take off the shell and see if anything is fouling the antenna.

Chuck,

Great idea to try swapping the command bases, will do. Thanks.


RoyBoy,

Though it's only 1 loco that has the problem, when it's on the test track with TMCC in the other room, it behaves exactly as it should.

I'm inclined to agree that it warrants a closer look inside. I'm not exactly sure of what to look for, though.

quote:

When the new loco is placed on the track and the layout powered up, its lights come on. However, there is no sound and no response to the BRK throttle. If I crank it 5-10 revolutions, the engine takes off very slowly. A few more revolutions and its speed inches up. Then all of a sudden, a slight movement of the know (15-20 degree rotation) makes it accelerate suddenly, but not runaway acceleration. Slowing it down requires many revolutions too.

Bob, this sounds not exactly the same, but quite a bit like what I was describing. Except with me it's way more than one loco.

And, I've long suspected what's really at work here are engine circuit board or speed sensor or cruise malfunctions rather than anything with ground planes.

Back to the subject of "secondary or local ground planes" - I think I understand now with the part about the absence of anything for the wall box to connect up to. It seems to me to be a lot easier to follow when I compare it to holding your hand over the engine.

Your body and hand aren't connected to anything either - unless it's the floor - yet it can work.

Speaking of which, would the hand thing work even if your feet weren't touching the floor?? Just curious about the scientific reasoning on that. That would help explain the wall box even more. Meaning, the box that isn't connected to anything is still obviously IN the wall of the house, so is that how this operates?

Oh, why the leaving one end of the ground loop unattaached??

One more btw - Bob, I noticed you said something about the engine malfunctioning regardless of whether the track's CB is on or off? Well, that would take signal/command issues out of the picture altogether. I guess that's obvious though...

If your layout is near a window, cound you run a wire from the outside rail to a ground rod?

Actually the ground that is needed has nothing to do with the outside rail, that is the return back to the transformer. The gound we are talking about is a reference plain for the signal wave to be identified with by the receiver in the engine. Sort of like your car radio antenna has the ground reference of the car body that is isolated from the signal it's self.

That said, your idea to run a line to a six foot copper rod that is pounded into the ground / earth could do the trick. But instead of running it to the outside rail it should be run to a wire that follows the track system and is layed beside the track. A 12 or 14 gauge wire is good enough for this.

These rods can be found at any electrical supply house, or even Radio shack. They are about 3/8 of an inch thick, have a point on one end with a terminator on the other end for your conductor / drop.

A couple of thoughts and observations.
1) Using a cheater does not insure a ground. A cheater is to make a 3 prong plug work in a 2 prong outlet. Many 2 prong outlets are NOT grounded. A 3 prong outlet without a ground wire is a violation of the electrical code. There is a tester available at most hardware stores or big boxes (Lowes or HD) which simply plugs in to the outlet. There are three lights which come on to indicate what is happening. Some also have a button to test a GFCI outlet.

2) The best earth ground is a seperate ground rod driven into the earth and connected by a copper wire to the ground plane wires. Using a seperate rod eliminates any interference from other electrical sources. The rods are 8 feet long, again available at big boxes. A slightly damp location for the rod is better than a very dry one.

3) The hand over the loco is a most reliable detector to determine if a ground plane is needed.

George Lasley

Ginsaw,

I'm sorry to hear you're having the same kind of issue as mine, and even worse, with multiple locos.

I'm also sorry for the confusion in my earlier post, responding to Chuck.

I have the double mainline layout in an upstairs media room (at least it used to be before the trains). To explore the problem with the loco, I set up a completely separate 12x4 FT test track in a nearby room. Both the layout track and test track have separate TMCC systems, CBs and CAB-1s. The problem loco only misbehaves on the layout track, and not at all the test track. I was trying to tell Chuck that the problems with the loco occur even if the test track's CB is off (obviously the layout's CB has to be on).

I hope you manage to find a solution to your problem - I'll let you know what ultimately happens with mine. I've been very pleased with how much Lionel has been willing to help through their email Talk to Us channel.

quote:

Originally posted by Ginsaw:
.

And on the outlet thing, my layout is in an add-on upstairs bedroom. The plug used goes into a wall box behind which is not an attic, but more of a large crawl space. When I did the trainroom wiring I had an electrician put in an exhaust fan back there and run a couple light fixtures so I could use the space for train storage.

Anyway, I was aware from reading here about the need for ground planes, although I admit to not totally understanding them. So, I asked him to check that wall box and see if it was properly grounded. The center prong does not go anywhere, and I recall he said it would be difficult to connect it up to any water pipes or to the outside ground pole. I think he added a device to the box itself which he said would help a little. Unfortunately I don't know now what that was.

.

I don"t know what the big problem is. If an acceptable wire route can not be found through the inside of the house the first thing an electrician would wont to do is run a EMT, or PVC pipe up the side of the house and bring your commercial power into your train room via that pipe, probably a 3/4 inch.
I have worked all over the country and I have never ran accross any codes that would not permit this. Of course, I have been away from any kind of power work for years and codes change all the time.
In any case I would talk to another electrician.