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Discussion Starter · #21 ·
you can
  • measure transformer voltage at various settings without it connected to track
  • check for a track short by measuring the resistance across the track connections
  • measure track voltage at various settings with transforrner connected to track
  • measure the resistance of the locomotive (across appropriate wheels). should not be ~0
  • measure track voltage at various settings with engine on track, prepared to stop if track voltage is substantially (??) lower than expected or if engine doesn't appear to start running
Thanks. Which are the appropriate wheels to check btw?
 

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Discussion Starter · #22 ·
The CW 80 uses a partial duty cycle sine wave to control power (throttle) to a loco. Compare that with a Lionel post war transformer that varies the amplitude of a pure sinewave to controll power. Most all budget and moderate priced multimeters will not measure the CW 80 output correctly. They measure the peak and calculate the AC RMS value from that. Since the CW 80 output always has the same peak, they'll always measure full throttle regardless of the throttle position. You'd need a high end "True RMS" meter to measure the effective voltage of the CW 80.

View attachment 597236
That's too deep for me. If I have to understand that to run a simple layout I got into the wrong game. :rolleyes:
 

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Discussion Starter · #23 ·
I had watched several vids on meters and Fluke is def the go to brand.

What I really need is a power source. I have none. I have no transformer now my brand new one won't turn on. I don't even know if it's the engine that's malfunctioning.
We have no hobby places I can go to test this out and no train friends :cry::cry:

Thanks again for the replies
 

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I had watched several vids on meters and Fluke is def the go to brand.

What I really need is a power source. I have none. I have no transformer now my brand new one won't turn on. I don't even know if it's the engine that's malfunctioning.
We have no hobby places I can go to test this out and no train friends :cry::cry:

Thanks again for the replies
You can test the transformer with a 12V auto bulb. Like a turn signal or stop light bulb. Strat with the throttle off and slowly increase to see if the bulb lights. It should light at least by half throttle or more.
 

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Discussion Starter · #25 ·
You can test the transformer with a 12V auto bulb. Like a turn signal or stop light bulb. Strat with the throttle off and slowly increase to see if the bulb lights. It should light at least by half throttle or more.
Can't test anything just now sadly. I am planning on ordering a mth z1000 though. Circuit breaker and then I don't run through a transformer every time I try to find a problem. Hopefully though the problem for me, was actually with the transformer and not the train
 

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A new question about the multi meter. I have a cw80 transformer and it was blinking red. I checked on things and it was fine, but then it seems to have blown it's fuse. In the interests of not wanting to blow transformers, how can I use a multimeter to test the transformer out of the box, then once hooked to the track, what test could I do on a 40" straight of Fastrack (a 10" then 30") to ensure it's appropriate to place my Legacy engine.
Is there a way to use the meter to test the engine to tell if it's what's causing the transformer to have problems?

I want to go minimal, adding factor by factor so I can detect exactly what changes, when and if there is a problem.

Thanks
I didn't think the cw 80 had a red light? Just a green one? Is it blinking? When you disconect it from the track and turn it on does it do the same thing? Did you make the dogbone layout mike posted? With back to back switches? Hook it up without the back to back switches, see if it works. On the old switches, when using them back to back you needed to add more insulated pins. Or in diffrent spots.
 

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Discussion Starter · #29 ·
I didn't think the cw 80 had a red light? Just a green one? Is it blinking? When you disconect it from the track and turn it on does it do the same thing? Did you make the dogbone layout mike posted? With back to back switches? Hook it up without the back to back switches, see if it works. On the old switches, when using them back to back you needed to add more insulated pins. Or in diffrent spots.
Ya, sjm9911, I was just starting on a straight piece of track, no loop. Just to get the engine up, running. It does blink red when it detects something is wrong. It's supposed to regulate and once the reason it went red is resolved, normal function is also supposed to be resumed. Believe me, I've done everything I can with this transformer. I had one cord, that of it's 120v power cord which i tried in several different outlets around my home. It doesn't turn on
 

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Ha. I was just talking to a guy yesterday about the fact that Radio Shack is still around.
In name only. It is not the RadioShack of old. When Len Roberts left the company as CEO the company started sliding down a hole it refused to recover from.
 

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Discussion Starter · #32 ·
Can somone advise when measuring resistence , what amount of increased resistence at connections of different sections of track, would actually make a notable difference in operation. Enough that you'd want to do something about that specific connection

Thanks
 

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If your loco is drawing an amp, a 1 ohm resistance will cause a 1 volt drop. V = I x R. And you have a lot of connections around a loop, between every track section. But remember, there are two outside rails carrying the same current but only one inside rail. So the inside rail is the weaker link.
 

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I have a Radio Shack Multi-meter (catalog number 22-174B) that is fully functional and in good working order. It appears I am no longer compatible with this meter. Due to my Tinnitus I can no longer hear the continuity tone.

I spend over an hour reading the manual, changing batteries, and such to get the tone working. While doing this my wife came out of the kitchen and yelled at me for the obnoxious sound I was making. I could not hear it at all!

I now have a Klein Tools MM450 meter which I can hear just fine.
 

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Discussion Starter · #38 ·
If your loco is drawing an amp, a 1 ohm resistance will cause a 1 volt drop. V = I x R. And you have a lot of connections around a loop, between every track section. But remember, there are two outside rails carrying the same current but only one inside rail. So the inside rail is the weaker link.
So my train is meant to run at between 8-18v. Is it logical then that if I applied say 10v to the track, the train would then face a relative 2v drop with a draw of 1 amp and then 2 ohms of total resistence. Let’s say 1 ohm per inter track connection. After this the train would drop below 8v of applied current and slow down/stop?
 

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So my train is meant to run at between 8-18v. Is it logical then that if I applied say 10v to the track, the train would then face a relative 2v drop with a draw of 1 amp and then 2 ohms of total resistence. Let’s say 1 ohm per inter track connection. After this the train would drop below 8v of applied current and slow down/stop?
Theoretically, yes. Consider that in a "loop", current carry capacity is coming from two directions. At the furthest point from the transformer lock-on, current is being carried from both halves of the loop. Near the transformer, resistance to the train is small from the near side and much higher from the far side. That some what balances out.

The rails themselves equate to fairly heavy gauge wire. The inter track connections are the weak point. And that is prevalent with older used, tarnished track pins and the condition of the receiving rail ends. Being new to trains, your new track should perform just fine.

In this Video, there's only one transformer lock-on. The loop is 42' in total. But I painstakingly restored the 60+ year-old track and paid special attention to the pins and receiving rails. And the small Marx motor in Santa's sleigh isn't a big current hog. But it is towing a decent consist of Santa's presents . All the cars' wheelsets were freshly conditioned for minimum rolling resistance. Many overlook that aspect when their trains slow down.

I can't recall which member wisely said in a recent post; Run the train. It will tell you if and where you need an additional lock-on.
 

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Discussion Starter · #40 ·
Ya Mike. First, great point about the wheels being capable of creating that resistence. I would think literally anything applied made of atoms contributes to resistance.
It was in one of my threads that we had the comment about the train telling me. Agree. I managed to have it run my elongated with no problems. It was 2 - 10" 6 30", and then 12- 48 curves to make the loop. I ran at a very low voltage and it didn't hesitate anywhere. (y)
I'm not worried about how to discover drop points now. I've got a train and a fluke115 now . I look forward to diagnostically analyzing my layout/s to learn about electricity and how my applications affect its flow.
 
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