Train Detectors

I listen on the scanner for the train detector's automated reports for some time. The total axle count has always been an even number ... and it makes sense, but would it ever be possible for me to hear an odd numbered total axle count?

If a steam locomotive with an odd number of total axles went over it, maybe?

i would say a FL 9

This is along the lines of my thoughts on this:

Could a detector ever miss an axle due to a malfunction and give a false report, number one?

Number two is if the detector is working fine, are there any locomotives and/or railcars in existence with a three axle truck on one end and a two axle at the other end, or four/three, etc?

But the idea of a steamer throwing off an even count is a good one. A 0-6-0 would do that.

Sometimes they'll skip an axle or two, there are rules that govern what you should do if the axle count is way off.

Avro, I was wondering about that, we didn't really get into detectors all that much in class. I was thinking if you got an axle count that was an odd number and your train wasn't in emergency already, I'd be pretty concerned.

detctors should count every axle from the first one on the locomotive all the way to the last car. If it's not working right it will report its self as not working. The train crew would contact the dispatcher and report the detector not working unless unless thows who are passing that area have been told about it befor hand. Amtrak trains will stop after passing a nonworking detector for inspection befor moveing on.

There are no cars with odd axles all trucks will read out as 2, 4, 6, or 8 axles on a single car. There are some TTX Cars with combos of 12 axles under one car and I have seen photos of cars with 18 to 24+ axles under them.

The TTX 2 Axle Splin Cars are no longer in service. Odd number axle counts would pick up on a steam locomotive or on EMD FL9's which had 5 axles the 5th axle was used on 3ed rail elictric lines these units did stray on occation befor Amtrak retired them.

SRS125 wrote:detctors should count every axle from the first one on the locomotive all the way to the last car. If it's not working right it will report its self as not working. The train crew would contact the dispatcher and report the detector not working unless unless thows who are passing that area have been told about it befor hand. Amtrak trains will stop after passing a nonworking detector for inspection befor moveing on.

You only have to walk the train under certain conditions as specificed in the timetable. A detector completely failing is different from an incorrect axle count. Depending on the railroad, if the number given is more than x from the real count, you have to go inspect the train. Sometimes you call the dispatcher and tell them, sometimes you do not have to. It's in the The Book.

It can be un-nerving to hear a detector give you 1 axle short, then the next on gives you two extra. I was once told by a signal maintainer that if a unit has a low snow plow then it can throw the counter off.

I once hit a deer right before the detector, and of course it went off with the dragging equipment alarm while the dispatcher was on the tower. He made me stop and examine my engines (it reported the defect near axel 5, 6 and 7). When he asked what my inspection revealed I replied "Deerburgers".

A question from someone who really doesnt know. What kind of detector is the one that has a rectangle box on each side of the track, about one to two feet off the ground? Is this a hotbox detector?

Hot Box Detector has 2 boxes on both sides of the rail with a heat senter in it to pick up on heat comeing off of the axles barings.

Draging Equipment Detecters have fins on both sides of the rail as well in the center.

High and Wide detecters are on poles on both sides of the tracks.

Some Detecters but not all give the following info as well: Axle Count, Train Speed, Out side Tempature/Weather Reports, Rock Slide Reports, High Water, and or a friendley safety message.

This might give an odd numbered axle count:

I recently waited for a self-propelled detector car (?) at a grade crossing on the CSX Chicago Line. In addition to the usual pair of two axle trucks, the car carried single axle mounted on swing arms at about the center of the car. This axle had wheels maybe 20” in diameter (the size of highrailer wheels) in contact with the rails.

There happens to be an HBD about 100 yards from the crossing. And of course I did not have my scanner with me (was on my way to work). So unfortunately I don’t know whether the detector actually sensed the mid-mounted wheels and thus reported “total axle count 5”. But I don’t see why it would not. ...FB

Detectors don't pick up on hy-rail trucks or small wheels on MOW equipment. The wheel are a lot narrower in width compared to a rail car which has about half an inch between the flang and the rail head while movieng on strate track in no way should a flang be rubing the inside of the rail while moveing with the exception of going around curves.

sammy wrote:A question from someone who really doesnt know. What kind of detector is the one that has a rectangle box on each side of the track, about one to two feet off the ground? Is this a hotbox detector?

this is a car reader detector, there are stickers on the side of the trains and when the train goes by, it reads the labels. Theres one in Mansfield, MA on the NEC MP 201

[/quote]this is a car reader detector, there are stickers on the side of the trains and when the train goes by, it reads the labels. Theres one in Mansfield, MA on the NEC MP 201[/quote]

I don't think them detectors that read them little colored bar tags are used any more due to the build up of dust, dirt, and rust covering them prevented them from working. Now there is a Small gray box thing that replaced the old colored bar code tags once found on Locos and Cars About the leaght of a normal site letter. I found one once it had aome letters and a number on it most likley the reporting mark and car number. Any ways I took it apart and found a small meter strip in it with 3 large flat battries about the size of a watch face in it.