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Grounding?

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Posted by Capt. Grimek on Sunday, December 7, 2014 1:20 PM

Thank you Randy! I'll check the throttle sistuation plugged in without a battery.

I have to be away (in a few minutes) for the day but will let you know what I discover.

So glad you're closing in on your dream layout design!

Jim EDIT/ADDITION:OOPS: Oh, sorry about the typo. Yes there are three 91s/Simplex Radio.

Raised on the Erie Lackawanna Mainline- Supt. of the Black River Transfer & Terminal R.R.

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Posted by rrinker on Friday, December 5, 2014 11:22 PM

 Power save causes problems because the throttles forget what they are controlling.

UR90? Or do you mean UR91? Because a UR90 is IR only, not radio, and it's direct line of sight - you have to point the top of the throttle at a UR90 for it to work properly. UR91 is simplex radio. Powering them actually powers the radio. Otherwise it is powered by the Loconet cable, and the UR units draw near the maximum allowed per device. Too much load drops the voltage - the power is only flowing through that thin telephone wire. Low voltage on the Loconet causes problems when you plug other throttle in.

 If you run a wire through the power hole of multiple UP panels, you'd probably use something reasonable size - like #18 wire. But that's only the + side of the circuit. The ground continues to go through the #26 phone cord, so you still have voltage drop issues. It's way overkill to use a PS14 on every single UP5 and UR - the URs should have their own, but one PS14 has enough power to support multiple throttles plugged in, so one can feed more than one UP5. Best way to do this is to parallel additional plugs on the PS14 so you can plug in to the power jack on the side of the UP5 - 4 or 5 UP5's per PS14.

 A good test is to look at the display on the DT400 when you plug it in. It will display Pwr and the voltage it sees - this will be the greated of power throught he UP or the battery. A tethered throttle does not need a battery. So use one without the battery and with everything operating, plug it in and see what sort of voltage you get. If it's 11V or more, things should be pretty good. If it drops much lower, then there are probably too many things plugged in to Loconet without power available to them.

                          --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Capt. Grimek on Friday, December 5, 2014 9:04 PM

Thanks Randy, I'll look and mull this over and talk with my wiring guy and get back to you in a couple of days.

I'm using a PS515 which came with the Super Chief system. I'm simplex (one of my throttles is a dt402 but simplex only.) I'll have a total of 3 or 4 throttles max for sessions. Usually 2. I didn't know anything about powering the UR90s.  I'll look into that too. What happens (or doesn't) if the loco net is the ground?

Would it be a good idea to ground to the outlet conduit until I accomplish that?

Does the power save cause problems/glitches? It's a pain having to climb down to plug back in anyway and have thought about doing that. I'll look up the CV and get that done.

What does powering the U91/2s give us. Just a better track signal? 

Thanks, Jim OP, sorry if I've high jacked your thread a bit, but your questions made me wonder if the missing ground was causing my issues.

 

Raised on the Erie Lackawanna Mainline- Supt. of the Black River Transfer & Terminal R.R.

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Posted by rrinker on Thursday, December 4, 2014 7:45 PM

 Sounds more like a radio signal problem than anything. For one, turn off the power save in the throttles. Also, do you have a PS14 powering the UR91 or UR92 (you didn;t say if it's simplex or duplex)? And if you also plug in more than 1 or 2 DT400s or 3-4 UT4s, I'd power the UP5's as well. Do NOT follow the diagram in the UP5 instructions and run the one wire, that makes the ground side be the Loconet cable. Instead you can run, or tap off an existing 12V DC bus and attach coax plugs to power each UP5. Radio Shack has the right connectors, I have a few packs but everything is buried in my basement so I don't have the RS part number handy. It's a 2.1mm I think.

                --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Capt. Grimek on Thursday, December 4, 2014 5:39 PM

Hi Randy. My buss is short as the layout is only 17' long and 8' wide. There are 3 power districts with PSX boards for short protection.

Basically, there are intermittent times when I'll have to shut down the system to "re-boot" in order to get locos to respond even though they've been given power to the track (cab lights are on, etc.)

This is sometimes during initial powering up but also if the battery saving indication is shown in the throttle and I have to replug in. (I think that indication is r-ps or something similar-not home right now to remind me.)

I sometimes have to also hit LOCO again to re-access the cab address and get the loco to again respond even though it's address is showing and the throttle beeped after plugging in.

This is a radio system with a 100/dt400. I recently realized that I now had some fascia up in front of the antennae location but everything operates fine otherwise even with other guys in the aisle during a session-plus I get similar behaviors when plugged in, having to hit the select loco button again.

I will be moving the antennae to a higher/open location when the lst city structure gets built this winter. In the meanwhile it works in every other regard so I don't think that's the issue.

After seeing this thead about grounding (my ground wire has been off for awhile) I wondered if that could be the problem. I'm going to, on the advice of my wiring buddy, attatch it to the outlet conduit.  The outlets and conduits run along the aisle side. The power buss and feeders are futher in mostly centered between the L girders.

I'd not thought about it being in one area of the layout. I usually experience this in the classification yard because I start most trains there. I'm pretty sure it's happened on the mainline occasionally also either after a plug back in throttle notification or initial fire up.  I have an upper city yard but haven't run up there lately.

Hope I answered everything. This "glitch" occurs about once per day on average.

Thanks! Jim

Raised on the Erie Lackawanna Mainline- Supt. of the Black River Transfer & Terminal R.R.

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Posted by rrinker on Wednesday, December 3, 2014 6:27 PM

 I don't think your glitches are related to grounding - more likely a signal issue. Does this happen in the same area of the layout? And how long is the bus line to the locations where the control issues happen? Do the bus wires run along that conduit for the lighting?

                --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Capt. Grimek on Wednesday, December 3, 2014 5:58 PM

Would taking the ground wire from the Digitrax 100 "booster" to the wiring conduit for the benchwork outlets be good enough?

I have been having mystery glitches that sometimes only resolve when turning the power off then on again. (Locos not responding even though they're getting track power, etc.)  Would taking the ground wire to the conduit be adequate?

Thanks, Jim

Raised on the Erie Lackawanna Mainline- Supt. of the Black River Transfer & Terminal R.R.

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Posted by 7j43k on Wednesday, December 3, 2014 4:15 PM

Bob,

 

Did you ground one side of your layout (low voltage) power?  If so, it makes sense that touching the ungrounded side of the layout power with a grounded trouble light would cause some problems.  Which, I guess, it did.

Ed

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Posted by Robert Frey on Wednesday, December 3, 2014 3:26 PM
Hi Randy, you are right I was lucky that my outlets were not mis-wired.  Yes, we do use 240V and with a stranded bare wire, house to the pole with a transformer near bye.  That’s 120V to ground or 240V line to line.   Very interesting information from you on the 100K resistor.  Got the 100K resistor static discharge information from:
 
Know of another grounding problem.  About 20 years ago, a friend built a new home. The freezer in his basement would not run, and the stereo in his living room was burned out.  The stereo was plug into a surge suppressor, and it also burned out.  His electrical box had two rows of circuit breaker, and had grounding terminals between them.  Turns out that the freezer motor was on one side and the stereo was on the other. The grounding screw between them had come lose.  Tighten the grounding screw, breaker on, the120V freezer motor started.  Turns out, the surge suppressor was from Radio Shack, and at that time it had an electrical guaranty.  He got a new Radio Shack surge suppressor and a check for his burnout stereo.
 

 

Bob Frey

Website: http://bobfrey.auclair.com

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Posted by rrinker on Monday, December 1, 2014 8:02 AM

 Well that would do it. And in a way you are lucky none of the outlets in use was mis-wired or it coul dhave been a lot more than 7.5V flowing in there.

 For static discharge that resistor should be a 1M ohm or more. You guys down there use 230V electric power, right? Worst case, miswired outlet, you could have the full 230V flowing between lines, with you as the conductor in the middle. With a 100K resistor, that's 23ma, enough to be painful. A 1M resistor, it's 2.3ma, you'll feel it but it shouldn't really hurt you. In the US, a 1M resisot and the potential for a standard household shock makes the current flow about 1.2ma, which is just above the level where you can even feel it. It's actually recommended to use more than 1M if the potential voltage is higher, around 2M for 230-250V, which drops the max current back to that slightly over 1ma level. The 1M resistor is standard for US anti-static bands. I haven't seen any specifically listed for other countries where 230V+ is the standard.

 The whole thing varies by system as well - some do a bipolar output around a common with an actual + and - 7.5V leg, others will output say a 7.5V and a 15V level above the supply common, and the common becomes the low side of the signal with the 7.5V level the actual circuit common, to give +/- 7.5V around the circuit common. So you need to be careful what connects to you AC supply ground, especially if the system is linked to other devices that may or may not be isolated - typical PCs are NOT, the case is connected to house ground, so ground loops can occur if the PC is connected by cable to another component that is plugged in to a different outlet.

                        --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Robert Frey on Sunday, November 30, 2014 11:56 PM
Hi Randy, I have seen the ROAR your Broadway Lion.  My reference link about the 100K resistor did not work very well.  Let me tell you a little story of how I damaged my Digitrax PR3.
 
 My Digitrax Chief and 4 Boosters are connected to an electrical common.  From this electrical common to Track A measured +7.5 Vdc and to track B was  – 7.5 Vdc.   I connected this electrical common to a cold water pipe.  (I thought this was a good idea.)  This pipe does directly though the basement wall into the earth.   (Now I know that as you say, this is 7.5 Volts looking for an earth ground.)
 
 My PR3 is connects to loconet and is on when the JMRI program is on.  It also has an USB plug to my computer.  The computer has a 3 prong plug to the outlet. Outlet has a ground to the electrical box.  My electrical box has a wire to a rod pounded into the earth outside.
 
I have trouble light with a metal case, and a three prong plug, and the hook on this case was also metal.  One day I forgot to turn off the railroad and the computer when I went under my layout with this light.  While I was working under the layout, I began to smell something electrical overheating.  I noticed that hook on the light was touching a solder joint of a feed wire to my track.  It was easy to trace the electrical smell to the PR3. The PR3 would no longer communicate with loconet.
 
 Sent the PR3 back to Digitrax, 3 weeks and $25 later, it was reported that a resistor had overheated.  I now have a 100K resistor between Digitrax electrical common and earth ground.  (The 100K to earth ground is for the discharge of static electricity.)
 
Bob Frey    

Website: http://bobfrey.auclair.com

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Posted by BroadwayLion on Saturday, November 29, 2014 4:52 PM

rrinker

 Assuming, of course,m the valve is installed correctly. It could have been done by whatever plumber installed the water heater in my house, with the red valve on the cold water inlet and the blue valve on the hot water outlet....wish I had THAT little bit of information so I don't accidently hire that plumber should I need repairs in the future.

                --Randy

 

Well I have examined what I could see of this setup. The ground cable that is attached to that pipe goes directly to the main power cabinets, and those simply have to be grounded directly from the MDU side of things. There is no way that THAT water pipe could ground anything, and so we must assume that it is the pipe that is being grounded and not the electrical system.

Now as for the water pipe. That does NOT go to ground anywhere. It comes through our buildings, through several buildings and only provides water to the building that i was standig in to take the picture. That 2" line must have been put there for some reason, but now all that is connected at the distal end is a pair of 1/2" pipes service two sinks and two outside hose nibs.

The water comes from the power house, where we have a huge (larger than a good sized steam locomotive) water tank. Once upon a time we had our own wells, and that tank provided water pressure to all of our buildings. Actually it still does, but now the water comes from the South-West Water District pipeline, where we have an account as if we were a city. So any water pipe entering our buildings from the water company would be on the other side of that tank which would effectively disallow it to be used for grounding anything connected to the mains. Maybe you can ground your record player amp to it, but little else.

In case of a short, you certainly would not want live current running around on that system looking for ground.

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by Robert Frey on Sunday, November 23, 2014 8:01 PM

DCC Common:    Provides a common voltage reference for all DCC components

“Grounding” of Booster Common: Not connected directly to an Earth Ground Water pipe. If done, use a 100K resistor to prevent static buildup.

file:///C:/Users/Public/Symantec/Downloads/Grounding%20and%20Commons%20Rev%20B.pdf

Example:  My PR3 to USB to Computer to Earth Ground via 3 prong plug.  My 60 Watt lamp, to Earth Ground via 3 prong plug.  Lamp case touched a DCC wire.  Result; send my PR3 back to Digitrax.

 

Bob Frey 

Website: http://bobfrey.auclair.com

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Posted by 7j43k on Wednesday, November 12, 2014 3:59 PM

rrebell

Looks like ground is on wrong side of valve?

 

 

As I said, it may not be a ground connection.

 

 

Ed

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Posted by 7j43k on Wednesday, November 12, 2014 3:56 PM

BroadwayLion
And what about a Piping Plover?

ROAR

 

 

 

Yeah, those Plovers are causing an awful lot of trouble.  I think the next code is going to outlaw them.  About time, I say.

 

 

 

Ed

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Posted by rrinker on Wednesday, November 12, 2014 7:48 AM

 Assuming, of course,m the valve is installed correctly. It could have been done by whatever plumber installed the water heater in my house, with the red valve on the cold water inlet and the blue valve on the hot water outlet....wish I had THAT little bit of information so I don't accidently hire that plumber should I need repairs in the future.

                --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by BroadwayLion on Wednesday, November 12, 2014 7:03 AM

7j43k
(my words) all metallic piping systems to be bonded to the service enclosure. This includes water pipes if they are NOT used as a grounding electrode. For example, if you have plastice pipe delivering water to your house, and copper piping inside, it has to be bonded. So, to, by the way is metallic gas piping. And even compressed air piping. And, frequently, the hot water piping in addition to the cold.

And what about a Piping Plover?

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by mfm37 on Tuesday, November 11, 2014 9:26 PM

Code here in Baltimore City as well. Or at least that's how the inspectors interpret it. Has to be before a PRV as well.

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Posted by rrebell on Tuesday, November 11, 2014 1:56 PM

rrinker

 It's not the water that conducts the electricty...

       --Randy

 

Just code out here.

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Posted by 7j43k on Monday, November 10, 2014 7:39 PM

BroadwayLion

I *know* that that is not the primary ground. MDU has a good solid ground in the transformer cabinet, we have our own grounds in several places. I do not know why that one was attached to the pipe. Maybe it is the pipe that he is trying to ground. I will suss out that line to see what is connected at the other end.

 

 

Section 250.104 Bonding of Piping Systems and Exposed Structural Steel of the NEC requires:

 

(my words)  all metallic piping systems to be bonded to the service enclosure.  This includes water pipes if they are NOT used as a grounding electrode.  For example, if you have plastice pipe delivering water to your house, and copper piping inside, it has to be bonded.  So, to, by the way is metallic gas piping.  And even compressed air piping.  And, frequently, the hot water piping in addition to the cold.

Different "authorities" enforce this section differently.  As they appear to do for the rest of the code.

 

 

Ed

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Posted by rrinker on Monday, November 10, 2014 8:25 AM

 It's not the water that conducts the electricty...

       --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by rrebell on Sunday, November 9, 2014 8:04 PM

Looks like ground is on wrong side of valve?

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Posted by BroadwayLion on Sunday, November 9, 2014 5:40 PM

I *know* that that is not the primary ground. MDU has a good solid ground in the transformer cabinet, we have our own grounds in several places. I do not know why that one was attached to the pipe. Maybe it is the pipe that he is trying to ground. I will suss out that line to see what is connected at the other end.

Water, like electric is our own system. Used to have a well, but now we are on the Southwest Water Project as if we were a city. City of Richardton has its own account and connections to the Southwest system. Our contract specifies water and pressure on demand. The city contract does not, they take a continious flow, but count on their own pumps to move water to the tower, and gravity to move water around the town.

We have a 6" connection to the city main for fire protection, but otherwise we have a 2" line connecting to our pressure tank in the powerhouse.

Back in the 19teens we were the power companay for the town. We continued to generate DC into the 40s and AC into the 60s. Now our new generator produces 100KW as a back-up system. Our typical use is 20-27KW, with 40+KW peak on Sunday when the church is all lit up.

The Richardton Rural Telephone Cooperative is now a big company, but our number (15) is the same as it was back then, they just kept adding new numbers in front of it as they got bigger. Today all phone service in Richarton is fiber optic. No more copper. (Except what I salvagted for the train room.) : )

 

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by mfm37 on Sunday, November 9, 2014 3:38 PM

Primary ground is direct to earth via a ground rod, ring, or plate. A water pipe is considered a secondary ground. That's because a water pipe does not or may not always remain in contact with the earth for at least ten feet due to corrosion, plumber changing it to plastic, etc. In addition, your water provider has no obligation to provide a good ground for a structure with its pipes so you can't count on it.

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Posted by BroadwayLion on Sunday, November 9, 2014 9:23 AM

7j43k
My comment, then, does not apply. I am guessing that the photo was shot in the basement, rather than on the top floor. I do strongly recommend not using a water pipe for a home-made ground. The proper and code-approved method is to connect one's new ground with the existing grounding system of the building.

 

Correct, the picture was taken in the basement.

On the railroad the ground is simply connected to the electrical system via a plug with only the ground wire connected.

But of course the whole railroad room is in a building that did not have grounding recepticals, but did have metal conduit. I put an extender box on the one outlet in the room and then tested the ground by lighting a 500 W bulb between the HOT and the conduit. It lit up properly and so I figured that the ground was good to go.

Anway, the common ground has no problems as long as it is grounded. If I remove the ground, the floating gremlins take over and cause problems.

 

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by 7j43k on Saturday, November 8, 2014 6:43 PM

Lion,

I assumed that you were showing a ground that you added for your own model railroad work.

From your further comments, it appears that the photo is showing the connection of the service's grounding electrode conductor to the water pipe.  My comment, then, does not apply.  I am guessing that the photo was shot in the basement, rather than on the top floor.

I do strongly recommend not using a water pipe for a home-made ground.  The proper and code-approved method is to connect one's new ground with the existing grounding system of the building.

As an example of unintended consequences, I saw a building where a plumber had replaced a good bit of the water supply system in the building.  He left the previous pipe that had the electrode grounding connection in place.  BUT the piece of pipe was about 5 feet long and not connected in any way to the new water system.  And that happened when the electrode connection was properly made.

 

 

Ed

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Posted by BroadwayLion on Saturday, November 8, 2014 4:58 PM

That connection was made by the electricians when they installed all new service, and connected to all of our buildings from this point, instead of from many drops. It also allows our back-up generator to serve all of our buildings.

That ground is probably for the electronics in the transfer switches.

Here is main service. Train room of LION is on the top floor, with those four windows.

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by 7j43k on Saturday, November 8, 2014 3:33 PM

BroadwayLion

 

 

 

 

  

 

 

I am an electrical contractor.

 

In the above example, I would have grounded to the conduit, not the water pipe.  This assuming the electrical system was installed properly.  And it does look nicely done in the photo.

 

 

 

Ed

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Posted by HO-Velo on Saturday, November 8, 2014 3:25 PM

For static electricity protection CVP Products/Easy DCC manual recommends grounding command station circuit board and throttle bus to a good earth ground, e.g. metal cold water pipe.

regards, Peter

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