Finally got most of my track (floating sectional) in and ready to go. I have soldered jumpers on all sections and clamped all turnouts plus jumpered around them. So I get ready for my first test of the track and pull out my Bachmann 2 truck Shay and it goes around but not very fast. I checked at the PS and at full have 18v. Then I spot check and get 18v everywhere. The track was cleaned with the green pad so it’s good. Any other suggestions? Plan to try the Connie tomorrow to see how it does.
Are you measuring 18V while the Shay is on the track running? (Under load)
Just grasping at straws with the information available…Have you run your Shay before with the same power-pack you are using now and noticed a difference?
The Shay runs slow anyway…even at full power.
It is not voltage that you need to check but current. The track with no engine will give you an open voltage of say 18 volts in your case, but add an engine under power and the voltage will drop depending on many factors. Load, resistance of wire, proper electrical connections, Loose rail joints, type on metal used for you rail, etc.
Every year my railroad was always checked before using it the first time in the spring. What was used is a HO MRC power pack that will only output about 2 amps.
I turn up the throttle to Max and with a DVM set to DC Amps I measure the short circuit load at the power pack track terminals. Should be around 2 amps, mark this reading down.
Now connect the power pack to your track and go around you layout with your DVM and check the track sections for the current, if you have everything electrically correct your readings on the track should be almost the same current reading you got at the power pack terminals. If not then work backwards from the problem point until you get a good reading, then start looking from that point forward for your problem.
I have found loose rail joints and rail clamps this way and after fixing the problems my railroad would work the way it should.
My railroad was divided into 8 blocks with individual power runs back to a central point, each block was checked this way. my railroad was computer controlled.
What are you using for a power pack?
How far away from the track is the pack?
What size wire are you using between the pack and the track?
I think if you follow Del’s suggestion and check the voltage while under load (the Shay is running) you will find that the voltage has dropped significantly. This is probably because the pack is either too small (not enough current [amperage]) or the wire between pack and track is too small, too long, or both preventing the current from reaching the track.
BTW - Voltage drop is a result of the pack’s inability to deliver the current demanded by the loco for any of the above reasons.
I didn’t think about checking under load. I’ll get out the stationary rollers today and check with load.
I know you have seen this before, this pack of power resistors allows me to put an 8 amp load anywhere, points out weak joiners easily with a voltmeter on either side of a joint.
(http://www.elmassian.com/images/stories/electronics/testing/resistor_.JPG)
I had not seen that before Greg. That’s a good idea. Man, you could fry up some steaks on that baby !
Neat. Those look like the Dummy Load for ham radios that Radio Shack used to sell.
Yep, 100 watt resistors… and it can make some heat!
Makes it really easy with a volt meter just start near the feeder and work away from it.
With stainless track and joiners I need all the help I can get with voltage drop at high amps.
Greg
Here is what I found today. First, quick background: approx 200’ all sectional aristo, all 14 ga stranded jumper wire soldered and for now, the PS is next to track connected with a 3 foot section of 16 ga speaker wire. Yes I know but this was just to see how the basic track was prior to side to side and final grading and ballasting. When I put the Shay on rollers at the far end, and cranked it up to the 18 volts, I still got 18 everywhere and the Shay appeared to run at what I normally expected and was drawing under 1 amp. But as I tested more then played with volume, it started to start and stop on the rollers. I touch it and it would start up. So I took it off and put on the Connie. Ran great and no starting/stopping normal speeds. Now it did derail on several of the switches where the Shay had no problems. While clamped with split jaw, I found some connections where track was not flush, causing a bump jump. It was very slight but after taking off the clamp and reinstalling it, all was fine. Which was all I was trying to accomplish, basic track trouble spot identification. Still have some switchs to work the bugs out, but realize now I need to go joint by joint and scrutinize carefully
Bottom line is I think I have some sort of pickup or whatever issue with the Shay but I can continue the process of track refining.
Thanks to all for input.
It could be a problem with the Shay if your Connie made it around OK besides the derailing. How are the wheels on yoru Shay are they clean? If it is running spotty even on the rollers you might have dirty wheels. I clean mine but squirting a paper towel with rubbing alcohol then placing one truck on the towel on the track and give it some juice. After a few seconds lift the engine and pull towel to a clean spot and put loco back down on it. You might will be surprised how much dirt comes off your wheels.
You mention the Shay has sound. If it is a Phoenix 97 board with a Big Boost there is a good chance that the track power pickups on the Shay are going bad. The second hand one I picked up with the '97/Big Boost had all of the power contacts melted. When researching why I found that the Big Boost can draw more current than the pick ups were designed for.
That evil-looking puppy’d put out enough power to burn right through a bad joiner! LOL
It pulls less than my 10 car passenger train!
Greg