The Home Machinist!

G,day....I have not seen a runaway electric YET, but I am only new to this hobby. I have been told that a meltdown in the control circuit can lead to it going to full on power. That is why I have wired a deadmans switch through my brake control. If I let go of the lever or apply the brakes the power is cut at a relay on the main cable going to the controller. I have to hold a slight forward pressure on the lever to run. I imagine it would be no great drama to fit a breakaway switch on the ignition of a petrol powered loco.
The Australian Association of Live Steamers requires deadman switch on all internal combustion and electric powered locos carrying passengers.

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Have a good one....John.

Chris, after this runaway incident, I did install a draw bar. When my son went into the Army he wanted to sell his critter, my wife said "no way, I want it" (I know right, color me surprised). so after a rebuild replacing the centrifica clutch system with an Eaton 7, I installed a permanent drawbar. This worked great for a while until Momma got a little too over confident and ran a tad too fast. I was just yelling in her ear to slow down when we derailed, causing the critter to go completely sideways. The end result was the draw bar was bent and twisted to the point that we couldn't put the engine and car back on the track. I had to disassemble everything track side and then push everything back to the barn, whereas if I had couplers we could have put it back together again. Something to think about.

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www.BuckinghamCentralRR.com

Another side to think about,
with an incident this big, you would have broken most couplers.
I have seen ductile iron, grey iron and aluminum couplers break in derailments. But I have not witnessed a bronze coupler breaking yet.
Can they? I’m sure with enough force.
My point is, I would not trust chain to keep and engine and engineers car together.
Just to many links to break. (I’m sure you can tell I’m not a fan of safety chains to began with.)
look at it this way, $45 to $50 dollar coupler or a $2 dollar drawbar
Don’t get me wrong, we are all free to do what we want. Just figured I would give you something to think about and pass on my observations.
Happy Railroading
Chris

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If it is not live steam. its not worth it.

Visit my website here.

Yeah, what's all this fuss about knuckle couplers when link-n-pin couplers work perfectly well?

One safety feature with my electric loco is that it is geared for about 5 mph max, so no run-away is possible. Maybe a "walk-away". Still, I plan to install a breakaway switch.

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Dan Watson
Building IC mikado in 1.5" scale

Fender: Don't you think it would be better to gear your loco to cruise at the track speed limit. Nothing makes me more angry than to get behind someone crawling along at 4-5 MPH when the normal track speed 6-7 MPH. Running at track speed is only common courtesy. Bill

Bill,
Don't worry, we never run at the same tracks. I can keep up with traffic fine at the places where I run. And what bugs me, is the people who go too fast to be able to stop safely.

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Dan Watson
Building IC mikado in 1.5" scale

Design your controls with safety in mind. At our club we had a run away of big gas hydraulic unit. Thank God it was when no on was in the way on the track. We caught it on up grade running towards it. The control did not fail safe when released. Apparently it was bumped and took off. The engineers cars trucks derailed and were destroyed by the time it was stopped.

Where I work we do FMEA's on our products, Failure Mode Efect Analysis, and list out every thing that go wrong and make sure that no single point failure will result an o "rats" incident. Some things need to look a more than a single point failure modes too. The moral is know how your controls and components work and fail, and build in fail safe for the right things. The dead mans brake pedal was invented for a reason and our controls need fail safe too. Being able to out run it dose not mean some one may not get hurt before it is caught or hurt running to catch it. Just a simple spring loaded valve, pot or switch that puts the engine in neutral upon release is mostly what is needed. And maybe a break away plug that kills power.

Another club member had an electric that some times when turned on would take off. Turned out to be the control was model air plane transmitter and receiver and the fail safe mode if the transmitter signal was lost was to fly at part power so the plan would slowly descend, but that needed to changed to no power in the program for the train losing signal. If he turned the train on before the control transmitter it would take off. Seems like a simple thing, but finding the root of the problem was not that simple, and he was knowledgeable on how the plane controls worked also.

With all the remote controls around to day it should not be hard to even make a remote activated kill switch. Car starter, car door lock, garage door, light controls, you name it. Wire to kill the ignition, or a power relay switch to cut battery power.

Rob

I have run at tracks from Chula Vista, CA in the South to Canada up North. I have run on tracks in Arizona and Utah. I have also run in Florida, Missouri and Tennessee. It has been my experience that the tracks out West are longer as is the average equipment size and hence the higher speeds. My home track has over 6,300 feet of main line plus numerous parking area sidings. On my trip back East in 2000 I had an oil fired Pacific and found it difficult to get compressed air for steam-up. Many steamers back East are coal fired and use an electric stack blower so the tracks don't have compressed air in the steaming bays. Out West we tend to oil or propane fire due to the fire hazard of burning coal. We get wild fires out here that are thousands of acres in size, not something you want to be responsible for. We get enough caused by lightning and careless use of cigarettes/campfires. BTW - I still travel and I just might go East again!!! Now I run a Bill Conner 4+4 Beam Engine (the Pacific was too slow) and a MCC GE Dash 9 (6.5 MPH cruise at 2600 RPM). Bill

Perhaps we could remember our younger readers (or those who just don't like cussing) and use different words?

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"One cannot learn to swim without getting his feet wet." - Benjamin Maggi
- Building: 7.25" gauge "Sweet Pea" named "Catherine"

We have both a key and a dead man switch (like on a wave runner) on our speeder car (built from the old Modeltec plans) for two reasons. The key is to prevent starting and the dead man switch is for in the event of something the operator can yank their arm and kill the engine. What I don't like to see are the engines operated with a remote control for model cars, airplanes, etc. I have watched many folks argue with the owners of these units until they are blue in the face, but the ones that I know of do not have a dead man switch of any type that could stop the power source in the event of a radio malfunction.

Jeff

Having been heavily involved with R/C controls for many years, I am also very concerned about interference from other radios (as well as the previously mentioned concerns of failures)

All you need is some kid, not far away, running an R/C car on an airplane radio (not legal, but that never stopped anybody who thought they were 'alone'), from being on your frequency and taking control of your locomotive, without knowing they were doing so.

I would personally like to see a main power to the wheels disconnect relay, connected to a seat sensor that would totally prevent any of these electric units (non-R/C) from moving ANYWHERE unless there is someone sitting behind it.

For cases where you cannot sit behind it (elevated steaming bay), then a spring loaded NORMALLY OFF switch that requires the operator to be standing adjacent to the loco would be the same thing functionally).

Electronics can and does fail, wires get kinked / shorted, etc and stuff can happen.

I think that the idea of something as large, heavy and powerful as some of these ic / electric units, sitting there with nothing but elecrtronic circuits to keep the wheels from turning to be a bit scary.

Granted, we live with electronics every day (part of the problem), and people assume that things electronic are safe and will only do what we expect. One of the problems is that the designers / builders of many of these locos have not done prober failure safety studies on what can happen and how they can be positively prevented.

Thoughts:

Any loco that uses an IC engine to create power may NOT be left idling when the engineer leaves the controls - out of the driver's seat, off with the IC engine, no exceptions.

Any purely electric loco must have a spring loaded switch that requires the operator to be sitting behind or standing adjacent to the loco. The wiring to this sensor may not be through the same bundle / connector as any other control circuits. Sensor must be tested every time the loco is brought to the club track for use. This sensor must positively disconnect the power to the drive motors in a manner that is totally independent of the speed control system used by the normal operation of the locomotive.

While Bill's "phantom" R/C control signal concept seems a little far fetched, I would like to relate two incidents of that exact occurrence.

You would think a large specialized, international, company like Lockheed / Martin (Yes the space vehicle boys) would have the funding, engineering, and planning to cover any and every detail, BUT think AGAIN. I have been personally involved with two r/c crane operation incidents. One, was an outside jib crane/hoist that would just start running by itself. At times, it would not follow commands when being operated. The installing company and another maintenance company were called out many times on this problem. Every time there was no problem found and the unit operated properly. Everything checked out 100%.

The second incident was much more scary. The overhead, inside bridge crane, they used to load out finished satellites, started doing the same thing from time to time. Again, all investigation found NO problems. Being a crane operator on a rental service crane, I went to both locations to do hoisting while the investigations were in process. One thing I noticed, every superior person had a walkie talkie for communications. I made a suggestion to one of the service persons that the use of all the two way communications might be the cause. He laughed in my face. BUT, when the r/c controls were eliminated and hard wiring used, all the problems stopped. Amazing. My guess is that the location of the first hoist was causing concentration of the radio signals at that spot. I believe the many different frequencies, of the two way radios, would combine and harmonize. When they hit just the right combination, it would cause the hoist to operate improperly. The second crane, being inside, would only react when there were enough people using radios inside that building.

A third and much less dramatic, continuing, occurrence is the use of the two way radios you can buy to keep in short range communication with friends or family. We use this type of short range radio for communicating with the crane operator when vision is obstructed. I choose an off the wall channel so there will be no interference. You can not imagine how many times there are signals bleeding into this channel. We can hear them but they can't hear us.

IF these things could happen in a remote location, with a company as advanced as Lockheed/Martin then I believe it could happen anywhere. I realize there are many laws and regulations covering radio frequencies and their use/application. How can we be sure? Are you willing to take that chance? In my opinion, injuries, time, money, and pride far outweigh any argument against a fail safe.

Good Luck,
Terry Miller