I need to purchase a volt/ohm meter for uses on my DCC HO layout and locos. Any suggestions would be appreciated.
Just a quick glance at the Harbor Freight Tools website, I see a couple for less than $10.00. You'll most often need DC, AC, and Ohms functions. Most multimeters will read the DCC pulse train signal level on the AC volts function. Ohms will give you the capability of checking for shorts, opens, and continuity.
If you're not really familiar with using a multimeter, it's best to start with a cheap one.
Thanks Tom,
I have seen them in Harbor Freight. Just didn't know if they would work with DCC.
Any volt meter will work. I have two. I have a cheap one that I got at Wal-Mart and another someone gave that came from Sears and has a digial display.
Will
There are cheap ones at Harbor Freight that go for $3-$5. Those are plenty adequate for model railroad use. I have like 3 of them in different palces so I don't have to run around trying to find one.
For SERIOUS electronic work you'd want somethign better, like a Fluke. But for hobby use there's nothign wrong with the $5 special.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Yes a cheap meter will be fine if you realize that the DCC bus readings will be inaccurate.
This won't matter after you come up with a conversion factor. You need something called a "true RMS" meter for accurate (vs precise) measurements. Those will cost considerably more.
Karl
The mind is like a parachute. It works better when it's open. www.stremy.net
I have three from Harbor Freight. Some times they have it for about $4.00. That is what I paid for each a couple years ago.
For reading DCC voltage, use the 200 volt AC position. On my NCE Power Cab, I read 13.6 volts AC at the tracks. Same thing at the club I belong to where we use the NCE Power Pro system. The AC voltage will drop a little depending on how many locos running.
I have a digital 'Oscope and the meter reading pretty much agrees with the 'Scope.
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.
I have 4 or 5 of the Harbor Freight el-cheapo digital VOMs and they are plenty good for model railroad uses. If you think you must have something to more accurately measure DCC Amperage draw and voltage, get an RRAmpmeter from Tony's Trains.
Harbor Freight's prices fluctuate from week to week. Yesterday, the digital VOMs were $2.99 in Tucson, Arizona.
Thanks All.
You guys are the best!
Yeah I grabbed up my $2.99 ones on sale. But they have an otherwise identical one for $4.99 or $5.99, the difference from the $2.99 one being the more expensive one has a transistor checker in addition the the usual volt/ohm/amp measurements. As a bonus, even the $2.99 one comes with batteries, and 2 years later I've still on the original set. Just remember to turn it off when done!
Tough to use for general purpose things and it doesn't do resistence/continuity checking.
I'm a big fan of Alton Brown on Food Network - and like him, I don't like single task tools. A standard cheap multimeter plus a buck or two worth of parts will do exactly what the RRampmeter does and then some. Or even skipping the parts (which serve to integrate the square wave to give a more accurate reading), it's close enough. There's little need to know the absolute exact to the 100th of a volt DCC track voltage, a cheapo meter will be within a volt of the 'real' reading anyway.It's not liek the meter will show 12 volts and you're really pumping 18 into your decoders.
Bottom line, a RRampmeter is a neat gadget, but hardly a necessity. A generic meter is much more useful, to check wiring, verify motor isolation,and all sorts of tasks related to the wiring of your layotu and installation of decoders.
davidmbedard What about a RRampmeter?
As far as I can see, there's really no need to know the actual DCC voltage. A regular AC meter will give a "close enough" value, and since it shouldn't change, and should be the same everywhere on your layout, you can use that value as your "standard" to tell if something is amiss.
I think an RRAmpmeter isn't a bad idea for measuring current. For one thing, it's too easy to get the settings wrong on a Voltmeter, and blow out the fuse every other time you measure current! And they don't like shorts.
Jeff But it's a dry heat!
The Ramp meter is designed to be mounted at the layout. It can be a help under certain circumstances.
Quiet helpful with large layouts and multiple engines, lighted passenger cars, stationary DCC operated items being run.
Most hand held VOMs or DVMs will only read current up to 2 amps. Above that, the protective fuse will blow. Even my $400 Fluke will only read up to 2 amps. For monitoring typical DCC, or DC operating currents, I would think you need a meter capable of 5, maybe 10 amps, depending on your power supply capability. I agree that an amp meter alone will not be that useful for general trouble shooting and testing.
DC
http://uphonation.com
richg1998 The Ramp meter is designed to be mounted at the layout. It can be a help under certain circumstances. Quiet helpful with large layouts and multiple engines, lighted passenger cars, stationary DCC operated items being run. Rich
A RRampMeter CAN be mounted at the layout be it also a portable tool. It will read voltage at the rail for DCC and when connected in series to the layout it will measure amperage used, without having to worry about a 2 amp limitation.
A multimeter is good for checking continuity.
dcfixer Most hand held VOMs or DVMs will only read current up to 2 amps. Above that, the protective fuse will blow. Even my $400 Fluke will only read up to 2 amps. For monitoring typical DCC, or DC operating currents, I would think you need a meter capable of 5, maybe 10 amps, depending on your power supply capability. I agree that an amp meter alone will not be that useful for general trouble shooting and testing. DC
..... Bob
Beam me up, Scotty, there's no intelligent life down here. (Captain Kirk)
I reject your reality and substitute my own. (Adam Savage)
Resistance is not futile--it is voltage divided by current.
My $3 Harbor Freight meter does 10 amps. Probably not super accurate but again, close enough for model railroad purposes. It's rtated to measure that up to 600 volts - although there is no way I woudl EVER use the flimsy probes it comes with on a 600 volt circuit. For 20 volts or less, no issue. A simple circuit can be used with the milliamp range on the meter to get a more accurate reading of th DCC amperage - Rob Paisley's is actually a highly accurate one that is essentially the same as the RRAmpmeter but there is also a simpler but not as precise circuit that will work - either way the meter is shielded from a short on the track.