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I finally got some track down on my layout the other day and put some of my rolling stock on the rails (No locos). Decided to put my Ohms meter on the rails and I had a 3.53k S/C across the rails. There are no leads connected to anything yet, I have been using alligator clips to test track with DC only. So only having basic track laid with no locos on the track I was confused by the short. So I started pulling cars off the rails with the meter on. Turns out it was both brand new out of the box Atlas NE-6 Cabooses. The interesting thing is that I bought both of the Caboose from two different hobby dealers, one in Ontario, Canada and one in New York, USA.
Both wheel sets on one caboose have one wheel in each truck with a 10k S/C. The weird part is that both Cabooses have the same 2 wheels with the same short (10k) and are in the same arrangement in the truck (I hope all that made sense). Two separate Cabooses with the same short circuit on 2 of their 4 total wheels per Caboose?
I have 4 of those. Bought 2 from one place and 2 from another. 2 have been running for over a month and the other pair are still boxed. Just for kicks I ohmed out the axle sets on all 4 cabooses and they checked fine.
That is just too weird. I can't believe that two different cabooses come from two different suppliers with the same issue on both cabooses. I even tried a different meter just to make sure with the same result. I probably would have never noticed the S/C in DC because the locos run fine, I think the voltage just blows through the short. But that can't be a good thing if I go DCC. I will give Atlas a call on Monday, they have always been good to me for any issues I have ever had.
10k ohms is quite a bit and probably wouldn't hurt a thing regardless of system. A DCC system probably wouldn't even notice it. It is most likely just a bit of lubrication between the wheel and the axle that is spanning the insulated bushing they use on one side of all metal trucks so they don't conduct one rail to the other.
I haven't done any research into train detection systems, but being that it is a caboose and the exact same resistance value, perhaps it is like that for a certain signal detection system?
Atlas started using wheels with resistors for their caboose trucks recently for those that use signal systems on their layouts. The resistance is so high that it wont damage anything and is normal for wheels with resistors. Nothing to worry about.
Nothing to worry about until someone has a bunch of them on a layout with several in parallel. Not likely but now and then you do get a person or 2 who will use a lot of one item. They should at least let people know they're doing it. Good Catch CWCanuck
Nothing to worry about until someone has a bunch of them on a layout with several in parallel. Not likely but now and then you do get a person or 2 who will use a lot of one item. They should at least let people know they're doing it. Good Catch CWCanuck
Well when you do axles on freight cars for signal systems you routinely put 10K resisters on at least 2 axles for EVERY single car. There are layouts like that with no issues at all. SO several cars wont make a difference. Now if it was 1 ohm then you might have an issue.
I myself am not familiar with signaling systems and I have no idea how they would work in relation to a to 10k short rolling by, But it does seem coincidental or intentional that both cabooses would have the same shorts on one wheel in each truck in the same arrangement on two different cabooses.
But like MGWSY said put more then three or four of these on a small layout and you are dropping down into the Ohms scale and a full on Short Circuit. I guess two is enough for me. I wish they notified you on the packaging or something that the caboose was resistor equipped.
Hmmmm maybe mine do offer some resistance? My meter is an old Radio Shack analog job and whatever scale it reads for ohms the needle never moved. One of these days I might have to move on up from the stone age and get a digital meter. Anyhow, thanks for the heads up about needing some ohmies for signals.
I just got off the phone with a gentlemen from Atlas in the technical department. He informed me that this is not intentional and that the wheel sets should not have any short circuits on them. He mentioned that he has seen this on "O" scale wheel sets when the wheels get pushed into the axle to far and touch, but my wheel sets are in gauge. Anyway he is going to send me four new wheel sets no questions asked and I am going to send mine back to him.
One thing I can say about Atlas is that their customer support is above and beyond any other that I have ever encountered. You can get a hold of them at any time during business hours. They are friendly and accommodating. All reasons why most of my equipment is and will continue to be Atlas.
That seems to bring up a couple of questions. First; did Atlas add the resistors during production and the gentleman you spoke with didn't have that updated info? Second; were the cars you bought brand new and sealed packages or maybe the place you bought them had added the resistors for a customer who ended up not buying the cabeese? Either way not much of a problem but as you said it would be nice to have known they were there.
I'm certainly not trying to point a finger of blame here. Just wondering how something got in there if it shouldn't normally be there. At least now we know what to do if we find an unwanted resistance in those axle sets.
On your radio shack meter, switch the knob to 10k, and if you have a good battery in the meter, you should get more accurate measurements. You should select the range on the meter that is just higher than what you expect: 1k would be too low, 10k would be ok for 3.5k readings.
Resistance readings require you to have a good battery, and you should 'zero' it before using (touch the probes together and make sure the needle reads 0, adjust as needed to make it read 0 while they are touching.)
yes, 10k ohm (and in some cases 15k) resistors are standard for block detection circuits.
and re: the conversation with Atlas: if you said "short circuit", they would certainly have said "no, there shouldn't be any." That's because 3.5k ohms ISN'T a short circuit. Zero ohms is a short circuit (in simple terms). He probably misunderstood if you called it a short circuit.
That seems to bring up a couple of questions. First; did Atlas add the resistors during production and the gentleman you spoke with didn't have that updated info? Second; were the cars you bought brand new and sealed packages or maybe the place you bought them had added the resistors for a customer who ended up not buying the cabeese? Either way not much of a problem but as you said it would be nice to have known they were there.
I'm certainly not trying to point a finger of blame here. Just wondering how something got in there if it shouldn't normally be there. At least now we know what to do if we find an unwanted resistance in those axle sets.
Atlas Caboose wheels have resisters hence 2 different packages of 33" wheels Caboose and Freight car. I am surprised Atlas doesnt announce this but its standard for the newer caboose models. And yes an easy fix is to pop them out but they will do no harm if left in there.
and re: the conversation with Atlas: if you said "short circuit", they would certainly have said "no, there shouldn't be any." That's because 3.5k ohms ISN'T a short circuit. Zero ohms is a short circuit (in simple terms). He probably misunderstood if you called it a short circuit.
I made sure that the guy at Atlas understood that I was talking kOhms and not Ohms, and as far as he was concerned there should not be any resistance between the wheels regardless of whether it is a High Resistance Short circuit 3.5k Ohms or a Dead short 1 Ohm. As far as I could tell he was unaware that there could possibly be a resistor in the axle. I left him a voice mail and I am sure I will hear back soon. He might just be unaware that they have changed something during manufacturing seeing as this stuff is manufactured in China.
Second; were the cars you bought brand new and sealed packages or maybe the place you bought them had added the resistors for a customer who ended up not buying the cabeese?
Both cabooses were bought at two different places, one in Canada and one out of New York. Both cabooses had the resistors in same axles in the same arrangement on each caboose which makes me think that it was done in production. Like you said I think that Atlas might not have received this update yet.
