What voltage are you getting?
Did you test the power supply itself? If that is putting out low voltage then you will definitely get low track voltage.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Hello Randy
Thank you for your detailed response. Is there a booster I could use or have I done something with the hand held cab?
Doug Edwards
Did the OP try reading the voltage at the PCP to see if there is a wiring issue with his track?
Joe Staten Island West
I've said it before - the el-cheapo HF meter is actually a BETTER tool, more accurate, for measuring DCC voltage than many much more expensive meters. Because it does absolutely no RMS whatsoever. A "plain" RMS meter, which can be found across a wide price range, are calibrated and calculate ONLY for sine wave AC, which DCC most definitely is not. Therefore, they read incorrectly. Always. There are more expensive "True RMS" meters which can measure not only sine waves, but triangle and square waves as well. However, few actually support frequencies as high as DCC, which means that an advantage they offer in being able to know the difference between a sine and square wave goes right out the window when measuring DCC. The cheapo HF meter just shows you the peak, which is the proper voltage of a square wave. All the Rrampmeter does on the voltage side is rectify the DCC and then (I sure hope so) adds in an ooffset for the loss in the rectifier.
The meter is not going to read 14 volts when there is only 6 volts on the rail. Nor is it going read 5 volts when there is 15 volts on the rail. Even with the general inaccuracy in the measurement, it wonl't be that far off. And consistency is what matters, especially on a larger layout with multiple boosters. You don;t want variations between booster districts, or your trains will speed up and slow down. Any inaccuracy in the meter is consistent, so if the meter reads 14 volts everywhere you're good, even if the ultra-accurate reading is 15 volts.
The PoowerCab power supply puts out 13.8 volts - that's the MOST you're going to get on the rails. Probably a bit less, since there are inherent loosses in the semiconductor devices that generate the DCC signal. While 12 volts is the NMRA standard for DC, most power packs put out 14 or even 16 volts at full throttle - so it's quite likely a loco will run slower after a decoder is installed than it ran on the old DC power pack without a decoder. Which is why a common voltage for HO is 15 volts. N and smaller is better off with lower voltage, both because the motors are smaller and more delicate and until recently most smaller scale locos ran WAY too fast at full throttle. The voltage of the PowerCab and other similar systems is a bit of a compromise to keep it simple and make one package work for anyone, no matter what scale (well, a PowerCab or Zephyr is not suitable foor O scale and larger where many of the locos draw more power than the system can provide - for ONE loco).
So what reading are you getting on the rails, in AC mode on the meter? Below 11 volts, there's probably a problem. Below 9 or 10, there's DEFINITELY a problem, and it's not the meter's ability to read DCC volts.
BNSF UP and others modelerTry measuring the voltage with a proper DCC tool.
If he says all his locos are running slow, do you think the "proper meter" is going to read a normal voltage? And if it does then what?
My Harbor Freight reads 13 something. I've never owned a Fluke or an oscilliscope so I'm never going to know if it's plus or minus 0.1 or 0.5 but 13 is a long way from 4.5 V
The OP has posted in the distant past that he had a Powercab so this is either new behavior on an old layout or maybe he built a new layout and and there is some wiring problem that has yet to be described.
Henry
COB Potomac & Northern
Shenandoah Valley
Try measuring the voltage with a proper DCC tool. Normal volt meters don't usually give out 100% accurate DCC readings. Also, trying buying a new power supply and seeing if that works.
I'm beginning to realize that Windows 10 and sound decoders have a lot in common. There are so many things you have to change in order to get them to work the way you want.
Thanks Tom, fixed it
http://cs.trains.com/mrr/f/88/t/276460.aspx
Mmmmmm...Different poster, Henry....Or, wrong link. FYI: Your first link is identical to the second one.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
You left us hanging after, you started your last thread:
From that thread, we gather you only have 4.5v at the track. Is this a brand new powercab, a used ebay powercab, or did this suddenly happen? Are you using the power source that came with the Powercab.
Is this a layout that previously ran well or is it a new build?
In another recent thread, Randy pointed out that a bad power supply may test normally with a meter but fail to put out power under load.
http://cs.trains.com/mrr/f/744/t/276546.aspx
As far as I know, the power output is not adjustable on the Powercab.
Instructions to do a reset are on page 59 of the manual.
nce power cab installed. all locos running very slow even new out of box loco. How do I increase voltage as it appears I'm not getting 14 volts.
Thanks in advance