Spring switch.

[chad thomas]

I've got a question about spring switches. Are all spring switches mechanical ? Can an power switch be a spring switch (non-CTC)?
If not what would a self correcting power switch be called (if anything)?

[zardoz]

Yes. No. Does not apply.

[mudchicken]

Zardoz: Are we rationing our words today?

Self correcting? Like taking it (the power switch in an interlocking)out of hand throw operation and placing it back in motor? Or the DS changing his mind???

Chad: You cannot, by rule & by signalman's common sense, have a functioning power switch in Automatic Block System limits. For similar reasons, you cannot in principal have an automatic switchman attached to a power switch (although it might have saved the power reduction gears inside the switch machine at a run-thru switch in an interlocking after a collossal gaffe by a train crew that otherwise destroys the machine.)

Does Chad know the difference between variable switch, rigid switch, hydraulic switch (mookie's current interest), electric lock switch, submarine switch, parallel throw switch and so on?

[Mookie]

MC:

I do hope you will tell us all what the difference is between a variable, rigid, hydraulic, electric lock, submarine, parallel throw and light switches.

I have another one of my headaches. Where DO you store all this information?

And my latest find - I take it that's the hydraulic switch - is that one of those switches that you go through and DON'T back up? It is set for one way only? (I seem to remember something in a previous life about this)

It's a really, really bad headache!

[D)]

[Anonymous]

Hi. In the UK we have a number of options that may fit.

First is a power operated hydraulicy driven self normalising point. These are generally used as traps to stop runbacks on hills. A route is set through the point and after the train has passed the interlocking returns the point to the position which will derail anything that runs back through them.
Also on remote line passing places a hydraulicly sprung point is used. It has detection fitted so that for facing moves a white light is displayed to the driver to prove the points are corecctly set. These are generally used in radio controlled sections.

[Mookie]

I'm starting to feel like English is a 3rd language with me...but I think I follow what you are saying.

I just remember that once thru, you don't back up. And the one I saw had a green and red light, which would probably be your white light. The green was showing.

And I was just getting over the dwarf lights missing - now this! (it's an inside joke!)

[jchnhtfd]

and I thought a spring switch was what the weather was doing...

[Mookie]

QUOTE: Originally posted by jchnhtfd

and I thought a spring switch was what the weather was doing...

Thanks Jaime - now that makes sense!

[chad thomas]

I think what I'm talking about would be a self-normalizing switch.

I'm talking about where a cabooseless train enters the main from a siding. After the train is clear of the switch it automaticaly lines itself back to the main.

[TheS.P.caboose]

With spring switches it's more about exiting a siding. Say you're operating a train and you're in the hole. The opposite bound trafic has cleared and the dispatcher has given you authority to head out on the main. As you leave, the crew does not have to get off the train and through the switch. There's a spring in there so the train can pass over the switch from siding to main without damaging the switch. After the train has passed the switch it realigns itself without aide by the crew.

If you're a train that has to enter the siding at a spring switch, now the crew has to get out , through the switch and realign it after the train has passed.

[edblysard]

Chad,

Old switchmans saying, "You can run through any switch you want to, at least once!"

To answer your question, yes, they are mechanical switches.

Spring switches are designed to be run through in a trailing point movement, they have a "spring", (really a spring/hydrolic ram, like a huge spring loaded shock absorber) that pushes the points back to the straight or tangent route every time a set of wheels pass through it.

You may not back over a spring switch until the entire train has passed through the switch.(doing so destroys the switch, cars, track and at least 90 days of your career)

Most spring switches have a manual method to line the switch to the diverging route in case the need arises to make a facing point movement into the diverging track.

They are almost always indicated by a white flag on the switch, with a black S on the flag.
Some have switch point indicators,(Mookies green and red light) to let a crew approaching a facing point movement know how the switch is lined.

Do not confuse a spring switch with a variable switch, which can be run through in a trailing point move from either track, it stays lined in the position the first set of wheels throws it to...it too is identified with a white sign and a black V....and often has a manual throw too, so it can be lined for a facing point movement.
Once the leading wheel set has passed through the switch, you may back over a Vee switch, it will stay lined for the movement the leading wheels set it for.

Other than these two switches, you should refrain from running through any switch, unless you want to be collecting your job insurance!

Ed[:D]

[Mookie]

printer is running!

[chad thomas]

Ed and spcaboose,
I am familiar with the MECHANICAL spring switch. I'm asking is there a POWER equivilant. I heard they have these on a BNSF line in S Dakota where there is no dispacher controll so the switch will line itself back to the main after the train has exited the siding.

Thanks for the info.

[edblysard]

Chad,
As far as I know, there is no "power" spring switch..no real need, the mechanical ones work fine, and have for decades.
The KISS theory works really well on railroads.....

Now, someone might have seen a spring switch with a switch point indicator...which sits on a electrical box....with a thick cable that runs to the points to read which way the swich is lined, so it can display the correct aspect....it would look like it was a power source for the switch, some of them are 2X3 feet in size....

Mudchicken will jump in here sometime and clear it all up...the guy builds railroads, so he will know....
Ed

[jeffhergert]

It sounds like your referring to what the GCOR calls an Automatic Switch. GCOR rule 8.19.
We don't have any where I work, but reading the rule it seems to be a dual control (power or hand) switch operated from the field. You stop, operate a push button that lines the switch for the siding, or if that doesn't work, operate the switch by hand.
There must be a track circuit protecting the switch. Once it senses all movement over the switch is complete (and is placed back on power mode if operated by hand) it will return to its normal position.
Jeff

[edblysard]

Okay,
Maybe we need to be a little more clear here...
A automatic switch(often incorrectly called a power switch) will be found in CTC only...

A power assist switch, electric or hydrolic, will be found in ABS, and dark territory.
We have one on the lead where I switch, electric, and I love it!

Automatic switches will line back, only after the crew restores it to the power function.
Read the rule, it tells you to restore power only after the leading wheelset has entered the circut for the diverging route...

When the switch circut is un-occupied for a set time, the switch will reset itself for the normal route...

Power switches will not line back, they work the same as a rigid switch, except they use a electric or hydrolic machine to line the switch, instead of a manual handle.
Someone still has to press the button to line it back.

Ed
[:)]

[mudchicken]

QUOTE: Originally posted by chad thomas

Ed and spcaboose,
I am familiar with the MECHANICAL spring switch. I'm asking is there a POWER equivilant. I heard they have these on a BNSF line in S Dakota where there is no dispacher controll so the switch will line itself back to the main after the train has exited the siding.

Thanks for the info.

Methinks there still is a communications problem/ disconnect here....Chad just described, in his second sentence, a spring switch in ABS or Dark/Territory...those are NOT switch machines.

Hello Chad?

[chad thomas]

Yes, I am talking about dark territory. Without any crew remaining the switch lines back to the main after the train is clear of the switch and on its merry way. I heard this was used where frequent meets happen in dark (possibly w/ ABS overlay) territory after cabooses dissapeared.

[edblysard]

Chad,
Sounds like your talking about a mechanical spring switch.
If you go look at one, it appears as if it uses a hydrolic ram, (it does) and it might have a switch point indicator, which would appear as a power supply..

But, they do not require power to work, simple physics make them function.

Ed

[dehusman]

You can have a powered switch in ABS. There were some switches that were thrown by the train crews activating a radio tone. There were powered switches in ABS.

Variable switch : A switch that when trailed through, the points remain lined in the position they were forced.

Rigid : a switch that has to be lined for a trailing point move, if you trail through the switch with the points lined against you the switch is "run through" and is damaged.

Hydraulic : a switch powered by a hydraulic system (as opposed to a pnuematic or electro-mechanical system).

Electric Lock : a switch with a electrically controlled lock that restricts the use of a hand operated switch. The electric lock can be unlocked by activating a timer or unlocked remotely.

Submarine : a slang term for a switch "stand" that is recessed in a street, usually with a hinged metal cover.

Don't know what a parllel throw switch is and a light switch is those little nubs that stick out of the wall next to the door.

Dave H.

[Anonymous]

In rushville indiana there is a brand new siding. It has "power' switches at each end this territory is abs with dtc block authority. To enter the siding a train will pull within 100 feet and enter a 3 digit code one the radio and enter the siding under signal indication when the train is in the clear and off the circuit the switch will restore itself to a normal position. to exit the siding a train needs to pull within 100 feet of the signal and the switch will line for there movement and once on the main it will line itself back. Now i'm not sure of its methods of moving the switch points. It'snot truly "dark" territory but as far as i know jax has no clue what goin on

[chad thomas]

bigchief,
That sounds like like the switch i'm talking about. Except a crewmember has to unlock a box and push a button instead of being able to key into the switch from the loco.

[chad thomas]

Thanks for all your input guys. I've learned a few things about switches.

[mudchicken]

That is still a hydraulic assist switch....not an automatic or power switch. Which would work in ABS or Dark territory/ yards. The terminology is causing most of the confusion. In a railroad environment, the terms have distinct meaning and cannot be used in a blanket sense. To do so would create havoc with the operating rules, design standards and general safety.

http://www.wch.com/wcht72.htm

What Mookie and Ed have described all along. (See the thread "Monday with Mookie" about 3 pages back....)

[chad thomas]

Do hydrolic assist switches have the "smarts" to know to line themselves back to the main after the train (and crew) is gone ?

If so thats the one.

[Hugh Jampton]

QUOTE: Originally posted by chad thomas

Do hydrolic assist switches have the "smarts" to know to line themselves back to the main after the train (and crew) is gone ?

If so thats the one.

Yes,, this is done using track circuits and a few relays.