defect detectors

[NSCOALDRAG]

Hello everyone,

Just wanted to ask if anyone had seen a good model of a detector, I'd like one that gave a verbal message if there is one out there. Thanks in advance!!

[cacole]

Out here in the desert, defect detectors are stretched out along about one mile of track, and involve quite a bit of equipment, so you would have to do a lot of selective compression to get one on a model railroad.

There's usually a hot box detector at each end, with a dragging equipment detector, axle counter, speed measuring detector, and IEC tag reader in between.  One even has a wide load detector because of a narrow bridge across the San Pedro River at Benson, Arizona.  In the middle is a large enclosure with the electronics and a radio relay tower, all surrounded with a chain link fence.

Along the Union Pacific Sunset Route, defect detectors are spaced about every 20 to 30 miles.

I don't know of anyone who makes a model of a defect detector.

You can hear defect detectors of the various railroads by listening to this site:

http://www.railroadradio.net/index.php

 

[Anonymous]

Out here in the desert, defect detectors are stretched out along about one mile of track, and involve quite a bit of equipment, so you would have to do a lot of selective compression to get one on a model railroad.

There's usually a hot box detector at each end, with a dragging equipment detector, axle counter, speed measuring detector, and IEC tag reader in between.  One even has a wide load detector because of a narrow bridge across the San Pedro River at Benson, Arizona.  In the middle is a large enclosure with the electronics and a radio relay tower, all surrounded with a chain link fence.

Along the Union Pacific Sunset Route, defect detectors are spaced about every 20 to 30 miles.

 

That's a very unusual installation! 

Almost all DEDs are less than 10' linear including the instrument house, and most HBDs are not any longer.  AEI readers are not combined with them but may be co-located.  Combined HBD-DEDs can stretch out over about 80 feet.

Typical modern railroad practice is to install a DED at every intermediate signal (8,000-foot to 10,000 foot apart) in concrete-tie territory, and 25,000-foot intervals in wood-tie territory.  The closer spacing in concrete-tie territory is because concrete ties are much more vulnerable to fatal damage from dragging equipment whereas wood ties can take quite a bit of abuse.

Typical spacing of HBDs is 50,000 feet.  DEDs and HBDs may be co-located and share the same instrument shelter, or have separate shelters -- depends on how the railroad wants to wire it.  AEI (not IEC) readers are usually installed at either end of a terminal or important junction in order to generate an accurate trainlist of trains entering and leaving.  There's seldom more than one or two every 100 miles. 

High-Wide detectors are applied to protect major through bridges and tunnels, and are often found entering and leaving major terminals, about five-to-ten miles out of the terminal, giving a load enough time to shift but not so much time it runs into something like a highway overpass.  They have nothing to do with the narrowness of the bridge -- by definition virtually all through bridges and highway overpasses are "narrow" -- but with achieving an acceptable reduction of risk.  

An old-style HBD depending upon railroad, can use anything from a 48" instrument case up to an 8' x 8' instrument shelter.  Typical practice today is an 8' x 8' or 8' x 10' instrument shelter.

Wheel-impact and broken-flange detectors are very rare by comparison.  There might be all of two of them on an entire transcon route.

As always practices vary by railroads and over time

S. Hadid 

[jeffrey-wimberly]

Two miles from where I live is a detector on the KCS main line between Hornbeck and Leesville. It has an axle counter, dragging equipment detector, hotbox detector, height detector and a couple other things. It takes up a length of track of about 15' and is located within 60' of a RR crossing. The nearest signal is 3 or 4 miles away, between Hawthorne and Leesville.

[Anonymous]

I have been working a project for the local electric utility, GIS mapping locations of their Consumtion Meters (the electric meter on your house), and picked up the meter serial number of a meter located at CSX M.M. 292, at a defect detector nearby the street. I would think it would be quite easy to model such a device from scratch, or from residue kit parts. Either way, I digress. Being a RR buff and Model RR buff, and having the digital camera at hand, I took six fairly quality photos of the facilities at this mile marker. (Not enclosed in Chain Link.) What attracted my attention was hearing radio chatter outside the shack while reading the power meter.

I can zip and email the photos to any interested party or post them to someone's web site for all to get. Send me an email at yahoo, just not everyone at once.

Hope this helps.

Elmo38smiley

[CSXFan]

 

Details West makes both a dragging equipment and hotbox detector for HO scale. Here's a link.

http://www.walthers.com/exec/search?category=&scale=&manu=Details+West&item=&keywords=Detectors&instock=Q&split=30&Submit=Search

[jamnest]

Several years ago there was a company that sold a talking defect detector for layouts.  I purchased one for use on my modular HO club layout.  The detector counted number of axles and gave the speed of the train, number of total axles in the train and the name of the railroad.  The detector had DIP switches which could be set to trigger a defect alarm based on the average range of axles in a train.  The detector would sound a defect warning and indicate the defective axle.  This was a real hit at train shows.  When I moved I left the detector with the club as the factory programmed railroad name in the detector was for the club.  I purchased the detector by mail order from an ad in MR.  I do not know the name of the company.  I wanted to purchase one for my home layout, but the company appears to be out of business.

JIM

[wranglerhuck]

Hello,

 I hope this helps. I found this wesite http://highlandpacificrr.com/merchandise2.html.  At one time I had the same website saved in my favorites(puter crashed) and I have been rattling my brains trying to find it again I hope this is what your looking for. If it is let me know..

[R. T. POTEET]

. . . . . . . . . . Several years ago there was a company that sold a talking defect detector for layouts. . . . . . . . . .

I wasn't aware of a talking detector but I do remember a number of years back one of the hobby magazines printed a circuit for an axle counter using an electric-eye mechanism. The proposal was to mate this with a computer generated random generator. When and if the random generator coincided with the axle counter it would trigger a warning bell with a message that displayed the "defective" axle and that car could be "set-out" at the next siding.

[HarryHotspur]

What's the purpose of an axle detector?

[HarryHotspur]

• To count all the Axles in a given train.  It then relays this to the driver of the train.

  David B 

  To a novice like me, this sounds amusing. Surely the engineer knows how many axles the train has when it leaves the station.  Is losing axles unnoticed along the way a problem?

  "Hey Bob! Looks like a couple of wheels just flew off the 3rd boxcar. Think we mighta lost an axle?"

  "I dunno, Jim. What does the axle detector say?" 

  

[fwright]

• To count all the Axles in a given train.  It then relays this to the driver of the train.

  David B 

  To a novice like me, this sounds amusing. Surely the engineer knows how many axles the train has when it leaves the station.  Is losing axles unnoticed along the way a problem?

  "Hey Bob! Looks like a couple of wheels just flew off the 3rd boxcar. Think we mighta lost an axle?"

  "I dunno, Jim. What does the axle detector say?" 

  

Actually, the axle counter reports where in a given train the defect is detected (how many axles back).  If there are no defects, then the axle counter is going to report total number of axles.  Useful information in either case - trains are too long to try to examine every axle for defect in the 1st case; the 2nd case detects any unwanted uncouplings (remember no caboose anymore) by comparing the current axle count against the full axle count.

Fred W

[HarryHotspur]

Thanks, Fred W. That's very interesting. What kind of axle defects would be detected? I assume it wouldn't x-ray the axles for potential stress fractures, but with today's techology, I might be wrong.