I started to solder the wiring on the attached and below schematic. Before going too far, I want to ensure there's current to each of the wires by testing w/ an Ohm meter. It reads that there's no power flowing. Thoughts? I touch one ohm meter probe to the DC output of my throttle and the red one to the track, but the Ohm meter shows no power. This happens even after I increase the power to the throttle. As shown in the schematic, I am working on the #1 red wire that flows from the selector to the track. No power hits the track even after I flip the toggle on the selector up and down.
I am following the method described here (under the testing wiring connections and testing power supplies discussions):
http://www.trainelectronics.com/Meter_Workshop/
If link doesn't work:
http://s44.photobucket.com/user/leekass/media/lee%20kass%20scheme02c_zps1b1bhopx.jpg.html
Thanks!
kasskabooseI touch one ohm meter probe to the DC output of my throttle and the red one to the track, but the Ohm meter shows no power.
Read whole reply, then do power off testing first.
1. What setting is your meter set for?
2. What it sounds like you are doing is trying to measure Amps, which on some meters requires the one of the probes to be moved on the meter. Or you may be wanting to do a continuity check. I will explain both.
If there is no load on the system (no locomotive) you should not have any current anyway.
You can also check voltage:
This can be done my setting up your meter to read DC Volts (typically has multiples of 10) 2V, 20V, 200V etc. Set your meter for 20VDC, turn on power pack and touch one meter to each rail.
Also you should go around and check for dead shorts with power off. This is where you set the meter to ohms. Good ones make a beep. Others will read OL. With power off go around touching one probe to each rail. If you get a beep or a number you have a short circuit.
As far as your wiring schematic goes, it looks okay to me, but I am no DC expert. The last DC layout I built was with my grandfather over 20 years ago. I have since switched to DCC, and am not looking back. But to each his own. There is nothing wrong with DC if it does what you want it to do.
You can also test continuity through the wires by touching one probe to the power pack + and the other to the track that is connected to the plus (again with power off) on the ohm setting.
Linking a photo of your ohm meter will help with double checking your settings if you are having problems.
kasskaboose I started to solder the wiring on the attached and below schematic. Before going too far, I want to ensure there's current to each of the wires by testing w/ an Ohm meter. It reads that there's no power flowing. Thoughts? I touch one ohm meter probe to the DC output of my throttle and the red one to the track, but the Ohm meter shows no power. This happens even after I increase the power to the throttle.
I started to solder the wiring on the attached and below schematic. Before going too far, I want to ensure there's current to each of the wires by testing w/ an Ohm meter. It reads that there's no power flowing. Thoughts? I touch one ohm meter probe to the DC output of my throttle and the red one to the track, but the Ohm meter shows no power. This happens even after I increase the power to the throttle.
Are you wanting to check current or voltage? Sounds like you are trying to check voltage if you aren't seeing any output when you increase power. If your meter also measures voltage, place it on the voltage setting and try the same thing. You should see a change between voltage and no voltage when you throw the toggle switch.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
If you are testing to see if power is coming through the wire, you need the meter set on volts, 20 volts is a common range on multimeters.
One probe goes to the DC terminal of the power pack - the one that DOES NOT go to the Atlas Selector. Touch the other probe to the other terminal witht he throttle turned on - you should see some reading. Touch the second probe to the screw on the Atlas Aelector - you should see the same reading. Touch the probe to the top screw of the Selector - With that switch set in the center, you should get no power. Switch it up, if the wire from the power pack connects to the top screw, or down, if the wire from the power pack connects to the bottom wire, and you should get power. Last stretch, touch the probe to the track to which you have soldered that wire to, and you should get power.
The other way to test is with all power turned off. Put the meter in continuity mode, if it has it - it should beep when the probes are shorted. Now you can touch one probe to the rail witht he wire solderedon, and the other probe to the screw at the top of the Selector - it should beep, if not, your wire is broken somewhere. If that works, test from the top screw to one of the side screws on the Selector. Depending on the switch position, it should beep - down connect the bottom side screw to the top screw, up connects the top side screw to the top screw. If that works, test from the side screw back to the power pack terminal, if that doesn;t beep, your wire is broken between the power pack and the Selector. If that works, you're good all the way from the power pack through the Selector and out to the rail.
Don;t forget that the OTHER power pack terminal has to run to the opposite rail as shown witht he black wires in the drawing or you will have no power across the rails no matter what. You need a complete circuit for power to flow - that's out one terminal of the power pack, through the Selector to the rails, through the loco to the other rail, and back to the other power pack terminal.
Don't worry, there is a video I've seen where they hand a battery, a light bulb, and a piece of wire to MIT graduates in engineering and physics and they can't figure out how to make the light bulb light up. Scary.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Multimeter links. Take your time reading through all.
I have four of these meters. Under five dollars each and do everything for me in model railroading.
Using one for model trains.
http://www.trainelectronics.com/Meter_Workshop/index.htm
Measuring voltage and current.
http://www.trainelectronics.com/Meter_HF/index.htm
Another one.
http://www.jameco.com/Jameco/workshop/techtip/Multimeter.html?sp_rid=MzEyMjY2MjcyMDAS1&sp_mid=4268910
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.
kasskaboose I started to solder the wiring on the attached and below schematic. Before going too far, I want to ensure there's current to each of the wires by testing w/ an Ohm meter. It reads that there's no power flowing. Thoughts?
I started to solder the wiring on the attached and below schematic. Before going too far, I want to ensure there's current to each of the wires by testing w/ an Ohm meter. It reads that there's no power flowing. Thoughts?
When testing for continuity, one probe is touched to one end of the metallic object to be measured and the probe to the other end of the metallic object to be measured. If there is no break somewhere in the metallic object, the ohm meter will show continuity.
Metallic objects for this purpose will include rail segments and lengths of wire. But, just because continuity is present does not ensure that power flow will be present.
Alton Junction
Ohm testing is resistance testing. Set the meter to ohm testing, if there is no resistance or low resistance then the meter swings over to the small end of the scale. No resistance means the two points are connected. High resistance means they are not or one or more connections are poorly soldered/connected/corroded - test with one probe on each side of the connection, do each connection point to see which one is the problem.
The ohm testing uses the battery in the tester, you can test the battery by touching the two probes together - if the meter needle doesn't move, there is a bad battery(s), no battery(s), or battery(s) inserted wrong. (or the selector switch isn't on the ohm testing).
Good luck
Paul
IRONROOSTERThe ohm testing uses the battery in the tester, you can test the battery by touching the two probes together - if the meter needle doesn't move, there is a bad battery(s), no battery(s), or battery(s) inserted wrong. (or the selector switch isn't on the ohm testing).
Or you have a blown fuse inside of the tester.
ROAR
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
Thanks greatly for all your help. Wiring is quite hazy for me beyond understanding the need for a complete circuit. In fact, I even concluded once in bed that the reason for no power was not having a complete circuit b/c there wasn't anything feeding the track.
Deep thanks for the informative feedback. Your comments gave me more confidence in the go slow and steady approach. I prefer testing one wire each evening and testing afterward than doing all the wires and nothing happening.
Never test ohms with power applied to the circuit. You will either damage the meter or blow its internal fuse.