Well. I have even had a Kato motor do the same and give up the smoke, cost me the decoder too! Nobody's perfect. Does the sellor have a return policy?
Jay
C-415 Build: https://imageshack.com/a/tShC/1
Other builds: https://imageshack.com/my/albums
Sorry, but the motors with high amp readings can't be used unless the short circuit is fixed. You don't want to overload the transformer and other circuitry in the DC throttles, because they can be damaged.
Most HO motors in my experience have a terminal resistance of 10 to 12 ohms. This will give a stall current of 1 amp at full voltage. The formula is voltage divided by ohms equals amperage (pretty simple). So, a 24 ohm motor will stall at 0.5 amps, a 12 ohm motor will be 1 amp, and your 1 ohm motor will be 12 amps.
_________________________________________________________________
If you're getting a winding resistence of down around 1 ohm (with the basic meter - I have a fancy desktop Fluke that can read down so low it can tell the difference between 1 foot and 20 feet of the same size wire) then there's a shorted winding. DC or DCC, that motor's no good. 25 ohms is about what an HO scale motor ought to be
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Brandon and Simon I want to thank both of you for your time on this mystery. What I am going to do different on the next 4 motors is not crank them up to full speed and see how the readings go. Just wondering with no break in and then cranking them up to full speed may have caused a problem.
Brandon, with you being a DC guy, could you use the motors with the high readings?
Ken
I hate Rust
Well I guess that is it then. The bad one of my three does have the odd reading down around 1 ohm. The average reading for the good ones is much higher than 10-12 ohms, more like 25 ohms. Still I think we can safely say that between Ken and I, at least 2 of the 10 motors we purchased have issues.
Simon Modelling CB&Q and Wabash See my slowly evolving layout on my picturetrail site http://www.picturetrail.com/simontrains and our videos at http://www.youtube.com/user/MrCrispybake?feature=mhum
That's very odd. These motors are the same ones used by BLI/PCM and Rivarossi. The one selling them is the former owner of Hobbytown of Boston, who also used these motors in their kits (the motors are old stock, at least 6 years old). I've never had one fail or run poorly.
A motor's electrical resistance can be read with the Ohm setting on a multimeter. On one of the bad motors, try hooking up an ohmmeter to the motor and turn the shaft by hand. The resistance for these motors should be 10 to 12 ohms on average. If the reading suddenly drops (little to no resistance), there's a short in the commutator. I don't know if it can be fixed, as I've never had this problem with these motors before.
I got 4 of these motors, 1 is already installed in a loco and I am not about to take it out for testing! The other 3 I was able to test this evening with a cheap Bachmann DC power-pack and my meter. 2 of them read a nice 0.8 or 0.7 amps at full power from the throttle. They were running about 1.2 amps when trying to stall them. The third was fine at low power but as the throttle cranked up the readings were all over the place way up around 10A, again not possible from this power pack. So it looks to me as if there is an issue inside some of these motors. Pete presented some reasonable sounding explanations for this. Also this motor does not nearly reach the same speed at full power as the other two, you can hear the difference. Two are quiet and smooth the other very loud and almost with a rattle. The starting voltages are 1.2V on the good ones and 1.9V on the poor one. So I guess it is buyer beware, you get what you pay for with cheap motors on eBay!!
When the motors overheated they destroyed the d123 decoders being used with them.To bad
at just under 6 bucks a piece they would've been a bargain.Know it wasn't a hemi,it was 361
cubic inch wedge.
redram58 It's the motor .Bought 6 on ebay.Used three to repower athearn engines all three overheated. Same exact motors.
It's the motor .Bought 6 on ebay.Used three to repower athearn engines all three overheated.
Same exact motors.
Boy I hope it is not the motors, I bought 6 of them as well and they where highly recommend by a person I trust. Darth Santa Fe has been using them and said they be good replacements for my aging Proto 1000 fleet.
Red Ram (by chances 392 Hemi) I guessing you where running them with DCC? If so, did you cook the decoder?When you said they ran hot, did you mean temperate wise where they felt hot, or just blow as decoder?
Simon, have you tested any of the other motors? What worried me is the second one started giving high readings as well.
Great, I thought I found a solution to get more engines up and running.
Cuda Ken
Lots of really good thoughts here, thanks for the feedback.
With Ken's "weekend" being Wednesday and Thursday, he works retail so is in the store Sat and Sun, I am not likely to get over there again until next week.
I think in order of things to do...
1. Replace the battery in his meter
2. Test his motor with my meter
3. Test motor with a different power pack
If we continue to get weird readings then it will strongly point to an issue with the motor. Between us we purchased several so it will be interesting to see if they all do this. It may turn out to be a lesson in what can go wrong with an eBay purchase!
I would be safe in saying that it is both. More than likely there are shorts in the armature of the motor or there is too much slop in the brush holders and the brushes are not across from each other. When running through the meter the back feed from the shorting armature is giving a false reading. I bet the motor does not reach the rated RPM and have the power of a good motor. Check for a high starting voltage also.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
How "pure" is the DC current from the power pack. Some meters may not be able to measure DC current with a high "ripple" content.
Well if you're familiar wiht using the fluke I'm sure it's a meter issue. Maybe it's at the low end of it's 10 amp scale. I still cant believe they sell those things for 4 bucks.
Springfield PA
The meter has a 10 amp and then a 200 ma and a couple lower scales. The 10 amp is very good for most readings I have done. On the 10 amps scale, you can read up to 9.99 amps. Two decimal places are just fine. This is not rocket science.
I have used the Fluke for many years and these cheap meters do just about everything I need. Yes, the Fluke is good for bragging rights.
Also, much cheaper to replace if you miss use the meter.
I only drag out the expensive meter if I need to read AC current which is rare.
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
I would suspect a meter glitch of some kind - to get reproducible errors a software bug would be a likely candidate. Low battery could also cause errors, but not as likely to be consistent errors.
Which brings up my recommended solution - check the readings with an analog multimeter.
One of my favorite EE profs: "We live in an analog universe, where everything is non-linear and time-varying. Why are we surprised when digital solutions that assume linearity and constancy over time fail occasionally?"
Fred W
With my multimeter, if I put it on the 10 amp setting it doesn't read the small fractional amps well. May I suggest you use a different range?
Battery life in the multimeter is also important as well as age of meter. BTW, my next one will be a Fluke.
Richard
You should have the black lead hooked up to the negative of the power supply, the other lead should be on one side of the motor. Then a wire should go from the motor to the positive side of the power supply.
I didn't see a listing for the 1100 but found the 1400 on the MRC site. That one only has 13va of power which is just under an amp. No way it's putting out 10 or even 3.
locoi1sa Ken and Simon. Is the meter an auto ranging type? Or is it a fixed setting? Are the motors in question a coreless motor? As an aside. I had a meter that was faithful for years suddenly give up the toast. The numbers were all over the place and would not stop climbing and decreasing in value no matter what I was doing. It was not a cheap meter and was never abused in any way. It still had the film cover over the LCD screen. One second it would work fine and the next it would go whacky. I am not saying Kens meter is bad but it does happen. Pete
Ken and Simon.
Is the meter an auto ranging type? Or is it a fixed setting? Are the motors in question a coreless motor?
As an aside. I had a meter that was faithful for years suddenly give up the toast. The numbers were all over the place and would not stop climbing and decreasing in value no matter what I was doing. It was not a cheap meter and was never abused in any way. It still had the film cover over the LCD screen. One second it would work fine and the next it would go whacky. I am not saying Kens meter is bad but it does happen.
As was said, he is using the 10 amp scale for DC current. The red probe inserted into the 10 amp socket. These meters do not have an AC current option.
The meter is the same one that I have three of and Harbor Freight sells them. I searched Google for Cen-Tech 7 Function Meter. I see them on ebay also.
Might be a low battery as I have had odd readings with a battery on the edge, These meters use a common 9 volt battery.
LOL ROFLMAO
Yep, seems like I should start up a Lemond Aid Stand.
Joe, you are correct. I need to get back over with my meter and see if we see similar results. It is also worth noting that anything that has electrons moving in it has a tendency to spontaneously combust when within a 20" radius of Ken!!
Simon:
Being the suspicious person that I am I would try Ken's motor setup with a different meter to rule out a meter glitch. If you still get the same results then I'm stumped too.
Joe
Just to confirm a couple of things here, Ken is using the meter correctly. It is in the DC amps setting and he is using it in series with the motor.
An old Athearn motor was giving nice consistent readings of about 0.5 amp with the throttle on full. So it appears the meter is working OK. A second motor was giving nice low consistent readings of 0.08A This all suggests that the test rig was working fine and the test procedure was fine.
If I had not seen it myself I would have thought something was amiss with the test setup, but the first of the new motors most assuredly was showing a reading of around 10A which then dropped down after some run time. After putting it aside for a while it did the same thing!
This morning I did the exact same experiment with my multimeter here and the same brand of motors just using a 9V battery as the source. I have an ancient Athearn motor pulling .3A and hardly moving and the new motor running fast pulling 0.06A
IMO there is no way that the motor yesterday was pulling anything close to 10A, it is not possible from the power source. This has to be an erroneous reading. What I don't like, is not knowing why this was a bad reading. The fact is, it was consistent and reproducible.
I bought 6 USA Plastic PN 530200/C6XO, think they where sold under the name Bear Motors and I am getting some real odd amps readings.
By the way Simon 1966 was over and saw the readings and confirmed I was doing the testing correctly.
First one showed at full power it was pulling over 10 amps? Ran it for awhile and dropped it down to 20 % power. Readings went down to 0.45 amps. Started turn the power back up and at one point at full power it stayed under 0.60 amps. OK, just need some break in time.
Second motor started out at 100 % power at 0.08 amps, OK that more like it.
Went back to the first one and ran the test again, back over 10 amps again. Then I tested motor # 2 again and it now up to 8.0 amps? What is really odd, as I stalled motor # 2 the amps started falling, not going up?
I think the Meter is working right, I tested some other motors, Old BB motors, RTR motors and a PK 1000 motors and there readings where what you expect to see.
2 other things that don't add up.
There is no way the little Rail Power Transformer 1100 could make 10 amps of power.
I was holding the motors in my fingers while running them and they never got warm, if they where hitting 10 amps they would have gotten Hot and pretty quickly.
Meter is a Cen-Tech 7 Function Meter. I have the black led in the common socket, red led is in the 10ADC socket and meter is sat on 10A setting.
Looking forwards to your ideas, I want to re motor some older PK's with these motors and not burn up decoders.
Thank you For Your Time.