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Voltage and Amperage Meters. Yes or No.

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  • Member since
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  • From: Knoxville, TN
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Voltage and Amperage Meters. Yes or No.
Posted by farrellaa on Sunday, February 24, 2013 10:41 PM

I have a pair of DC volt (0-20VDC) and amp (0-5ADC)meters that I had planned to use on my control panel when I had DC. I now have DCC and wondered if there was any advantage to having a Volt or Amp meter connected to my Zypher? I assume I would have to use AC meters for DCC? Any thoughts on this or suggestions?

    -Bob

Life is what happens while you are making other plans!

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Posted by jrbernier on Sunday, February 24, 2013 11:33 PM

Bob,

  I really see no advantage - But it can be done.  The problem is that most meters are designed to read AC values at 60 hertz - the DCC signal is mush faster.  DCC Specialties has a RRampMeter that can do what you want.  They have portable ones, and panel mount versions:

http://dccspecialties.com/products/rrampmeter.htm

  One of our club members has one of the portable ones, and we used it to verify we had good voltage as we wired feeders between the rails and the bus.

Jim

Modeling BNSF  and Milwaukee Road in SW Wisconsin

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Posted by richhotrain on Monday, February 25, 2013 6:19 AM

jrbernier

Bob,

  I really see no advantage - But it can be done.  The problem is that most meters are designed to read AC values at 60 hertz - the DCC signal is mush faster.  DCC Specialties has a RRampMeter that can do what you want.  They have portable ones, and panel mount versions:

http://dccspecialties.com/products/rrampmeter.htm

  One of our club members has one of the portable ones, and we used it to verify we had good voltage as we wired feeders between the rails and the bus.

Jim

I have a RRampMeter, and I love it.  When wired in-line, it continually reads out volts and amps.

However, be advised, when used as a portable device, it only reads volts, not amps.

Rich

Alton Junction

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Posted by gandydancer19 on Monday, February 25, 2013 9:07 AM

The volt and current meters used for DC were an advantage in that they could tell you what the locomotive motor was doing.  That is not the case with DCC since there is power on the track at all times, and usually more than one locomotive on the track as well.

The RRampMeter is basically a troubleshooting device.  It can be connected to the track if you wish, but I don't think there is any advantage to doing it.  If you just want to make sure there is power on the track, use a light bulb or LED with a resistor.

Elmer.

The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.

(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.

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Posted by richhotrain on Monday, February 25, 2013 9:29 AM

gandydancer19

The RRampMeter is basically a troubleshooting device.  It can be connected to the track if you wish, but I don't think there is any advantage to doing it.  If you just want to make sure there is power on the track, use a light bulb or LED with a resistor.

One big advantage of the RRampMeter is the amps readings when the meter is wired in-line.  If the amps are approaching the limits of your booster, the RRampMeter is a convenient way to visually make that determination.  An effective way of determining whether you need to add another booster to your command station.

Rich

Alton Junction

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Posted by cacole on Monday, February 25, 2013 9:32 AM

We have a Rrampmeter connected to our club layout's NCE DCC system so we can monitor current draw when more than one train or multiple locomotives are running, but its usefulness has been negligible.

The only time we look at it is when there is a derailment and the system shuts down, because the Rrampmeter goes dark.

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Posted by richhotrain on Monday, February 25, 2013 9:50 AM

cacole

We have a Rrampmeter connected to our club layout's NCE DCC system so we can monitor current draw when more than one train or multiple locomotives are running, but its usefulness has been negligible.

The only time we look at it is when there is a derailment and the system shuts down, because the Rrampmeter goes dark.

LOL

But it looks cool mounted on a control panel, no?

 

Alton Junction

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Posted by rrinker on Monday, February 25, 2013 10:44 AM

 Pretty much my thinking. It would certainly look cool - but thus far I have not needed to have anything of the sort wired in to my system.

        --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by john.pickles87 on Monday, February 25, 2013 1:47 PM

Hi Bob,

I've an old Hornby 12volt 2amp transformer with a Gaugemaster DC controller with pair of meters wired in between the controller and a pair of alligator clips.  In me DC days this set-up was wired into my branch block (about 15ft of track), to check out any new locos or ones I'd been working on.  Still got it, now I use on a yard of track (Me programing track) to check the stall currant draw on locos before chipping. So don't chuck em mate.

Be in touch.

pick.

?
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Posted by gregc on Monday, February 25, 2013 4:42 PM

Since you have the meters, I assume you'd prefer to put them to use rather than buy DCC compatible meters.

Measuring DCC track voltage doesn't have much value, but measuring track current could be useful to evaluate the performance of engines, as well as know if you're getting close to limits of your DCC booster.

However, to use your existing DC meter, I believe you would need to a full-wave bridge in one path between the DCC supply and track, to provide correct polarity to the meter.   The bridge diodes would need to be capable of handling the full current of the system (at least 5A).   There would also be a voltage drop across those diode.   I believe Schottky diodes have less voltage drop.

greg

greg - Philadelphia & Reading / Reading

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Posted by farrellaa on Monday, February 25, 2013 11:30 PM

Thanks guys, kind of what I expected but hate to have these two new meters sitting on the shelf. I may try to use them to check stall amps on some of my older locos before I put decoders in them. If not then I guess I can put them on Ebay and hope someone can use them 

   - Bob

Life is what happens while you are making other plans!

  • Member since
    February 2002
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Posted by rrinker on Tuesday, February 26, 2013 8:10 AM

 If you have lots of locos to convert, and expect to be buying more that do not already come with decoders, then probably the best use of meters is not ont he DCC system, but on DC for checking things like stall current on unknown locos to make sure a decoder can handle the motor load. Watching the ammeter on DC while slowly moving the loco on a test track can also detect sticky or binding mechanisms, if it's an analog meter - it will flutter as the current draw momentarily rises when there is a bind then drop down when past the stickly point.

        --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Soo Line fan on Tuesday, February 26, 2013 10:21 AM

Another idea is to use the meters to monitor accessory power. Maybe use the amp meter for your switches and the volt meter for lighting.

The ramp meter may not be a bad idea. There are DMMs capable of reading high AC frequency. For example, a Fluke 87 V can measure AC v up to 20 Khz with a 2 +/- accuracy. There may be cheaper options as the Fluke is $350. So for the price, the ramp meter is probably looking pretty good.

Jim

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