OK... I'm sick of getting 18.4 or 18.2vac... then, immediately dropping to 17.8 or 17.6vac. Which RMS Multi Meter are y'all using? I'm sure that most of you have very expensive RMS M/Ms... but, is there a decent one out there in the 80-100 range that you would recommend? Thanks... and, Rock On!
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Simpson 260. But it is a little above that range.
Dennis, do you want an analogue or digital meter? New or used?
One thing you could do to minimize voltage drop in the readings with your present meter is to measure the voltage with a moderate load connected to the power source being measured, such as an 18 volt light bulb or a power resistor.
Steve, I don't have a preference as to analogue/digital. Used is fine if I know the individual... otherwise new would be my choice. Now convenience, because I'm in the attic with some reach issues or in the eave behind the knee-wall or under the layout... the less this septuagenarian has to tie into/set-up is probably the better.
Longtime Fluke multimeter user here. There are many used ones available on the usual auction site, within your price range. Many of them are nearly indestructible. Don't bother with the older manual-range-switching models, which were quite good, but whose time is not now.
Hi, that voltage is not CRITICAL as long as you set close to 18 VAC! your voltage will change as the current draw changes. especially if your adding other engines while another engine is running in DCS. as Steve H has already said!
Alan
You’re gonna have to up the anty if you want a something like a Fluke with true RMS, ……usually around 175-200 bucks,….like mentioned above, I’ve only ever used Fluke in the shops ……some of my Fluke meters are 30-40 years old now …..I have a 115 in the RR shop, it’s true RMS, ….I think I caught it on sale for like 169.99, ……something like that ….
Pat
I got a Klein. Home Depot sells them. I'm thinking around a $100.00 is what I paid.
Amazon has it for $85.00
I use a Fluke at work. It's excellent and takes some serious environmental punishment. But it is pricey.
I use a Harbor Freighter at home. So far it hasn't failed me but I have no clue on how good it really is. Maybe someone with more electrical wisdom than me can comment on that.
Thanks guys! I'll bump up the give a bit and see if I can get the Fluke into the house.
Hi here is the 115 true RMS fluke Pat was talking about!
Fluke 115 True-RMS AC/DC Digital Multimeter - at the Test Equipment Depot
Alan
@Dennis-LaRock posted:OK... I'm sick of getting 18.4 or 18.2vac... then, immediately dropping to 17.8 or 17.6vac. Which RMS Multi Meter are y'all using? I'm sure that most of you have very expensive RMS M/Ms... but, is there a decent one out there in the 80-100 range that you would recommend? Thanks... and, Rock On!
Dennis, it's a little unclear if the symptom you're describing is actually related to a non-RMS voltage reading or whether it's actually the differences between different readings on different meters, or with different loads applied to the same source.
True-RMS reading meters are designed to accurately measure AC voltage of non-sinusoidal waveforms (other than pure sine wave). Chopped sine wave voltage output examples within our hobby would include MTH's TIU (as Alan mentioned) Z-1000, 750 and 500 Controllers, as well as Lionel's Legacy PowerMaster, CW-80, and others.
I'm guessing that the issue you're wanting to solve may either or also be related to the typical output voltage dropping from a source when an additional load is applied to it, explained by Ohm's Law.
Unless a meter has a low input impedance (option), its voltage readings of a source will still drop when a greater load (lower resistance) is placed on the source. I had a Fluke 115 that I used for a long time and it is a very good meter, but it also has a high input impedance and will still give varied voltage readings with load changes. If you want to spend the money for a Fluke brand meter with the Low-Z option, then either the 114 (non-RMS), 116, or 117 do this. Here is a link to Fluke's description of meters they offer with Low-Impedance: https://www.fluke.com/en-us/le...-digital-multimeters
For many years now, I've used a few $10 meters that I keep in various handy places and in vehicles. Any of these will provide readings that are accurate enough for our purposes as long as the sources have a nominal load attached (a low impedance such as an incandescent bulb or low value resistor). On my electronics workbench is where I keep my better test meters.
For occasional use, here are some other lower cost brands of True-RMS reading & Low-impedance meters that should be fine for our train related needs: https://www.google.com/search?...mpedance+Low-Z+meter
I've been using the Fluke 117 for years, ever since my 20 year old Fluke 77 finally went out of cal. I looked into calibrating the #77, but it was more expensive than just buying a new meter! 
I'll put in a plug for Ideal meters. They're sold at Lowe's or Amazon. I have this one. I've used it for over 10 years.
Steve, I understand that if I put different loads on the power district I will get different readings. Right now I am talking no trains or other consumers within any particular power district. I'm cleaning up the wiring after 5 or 6 major changes to the layout and buttoning everything up to start on Signals, Structures and Accessories and the less I have to go back and re-do the better. Besides... I deserve a Fluke! 
Dennis, sounds good! If I were buying a Fluke with the RMS and Low-Z features, I'd second John's recommendation for the 117.
@gunrunnerjohn posted:I've been using the Fluke 117 for years, ever since my 20 year old Fluke 77 finally went out of cal. I looked into calibrating the #77, but it was more expensive than just buying a new meter!
Fluke 177 all the way. You can get used ones out there fit 100-150 bucks. Just make sure you get good fluke meter leads
Does Pat's 115 make the grade here? I've got the eyeballs on a 115 right now.
As I understand your issue, the 115 will not sufficiently load the output like you seem to want; it has a high input impedance. Otherwise it's a good meter.
That being said, the 117 is about $20 more and has both features you seem to want (True-RMS and selectable Low or High input Impedance. The 177 Gary mentioned, is also a great meter, has the same features as he 117 with Auto-Ranging, but close to $200 more.
@Dennis-LaRock posted:Does Pat's 115 make the grade here? I've got the eyeballs on a 115 right now.
Everyone’s got their own preference…..I’ve fed my family, and made a very good living trusting 115’s so take that for what it’s worth,…..😉
Pat
Too much is being made of the need for a true-RMS meter for model train applications. As @SteveH points out, a True RMS meter is not needed for sinusoidal waveform work. @Dennis-LaRock is concerned about measurements in the 18 VAC range. At 18 VAC, all transformers and controllers--including chopped waveform ones--are producing a near pure sine wave!!!
If you are looking for a good overall meter with a current clamp and willing to spend $100, I would go with the Harbor Freight CM-1000A which you can get for $90 with a coupon. It has features rivaling my $500 Fluke 287 meter (except for computer logging).
Dennis: Are you sure that you're not measuring the voltage drop between the transformer and the track? The wire to the track will yield a small drop in the range that you mentioned; 18.2 to 17.8 would not be unusual. Or perhaps I'm not understanding where you are getting the drop in the readings. Just thought I'd ask.
@Bruce Brown posted:Too much is being made of the need for a true-RMS meter for model train applications. As @SteveH points out, a True RMS meter is not needed for sinusoidal waveform work. @Dennis-LaRock is concerned about measurements in the 18 VAC range. At 18 VAC, all transformers and controllers--including chopped waveform ones--are producing a near pure sine wave!!!
Well... not really!
And the winner is:
The TIU is interesting when fed with a pure sine wave. Open PDF to see full report.
@Bruce Brown posted:Too much is being made of the need for a true-RMS meter for model train applications. As @SteveH points out, a True RMS meter is not needed for sinusoidal waveform work. @Dennis-LaRock is concerned about measurements in the 18 VAC range. At 18 VAC, all transformers and controllers--including chopped waveform ones--are producing a near pure sine wave!!!
If you are looking for a good overall meter with a current clamp and willing to spend $100, I would go with the Harbor Freight CM-1000A which you can get for $90 with a coupon. It has features rivaling my $500 Fluke 287 meter (except for computer logging).
That's not really true. Try measuring the out put on a ZW-l with a standard meter. It will show low voltage output.
That's why I bought the Klein TRMS meter.
I was trying to keep it simple but I'll broaden the description of what I'm looking for. I do understand that consumer load and resistance (i.e., a long thin cable will have a higher resistance than a short fat cable). This also goes beyond the trains...
Firstly, the 30 or so year old Extech MultiTec 310 is probably getting a little long in the tooth... however, I will keep it around as it can handle a ton of amperage. I often get voltage drops that are inconsistent from one moment to the next in the exact same location and that inconsistent drop can vary considerably... up to a full volt or more. I have the same 'consistent' accuracy issues when working with digital signals primarily when dealing with my HVAC. Other features... Diode and capacitance, AC/DC auto detection would be nice as would audible continuity and non-contact voltage detection would be particularly handy around the house. Oh! and, back-lit!
My Fluke 117 has pretty much your whole list. I don't have AC/DC auto detection, and I don't want it. Many times I want to measure the DC component of an AC waveform, I don't want the meter deciding for me what mode to be in.
I have an UNI-T UT61E that I got for around $60 several years ago. Amazon has them for around $75 now. It's been really good for me. At the time this was ranked as a really good electronics hobby-level performer for the cost. This one you can even hook up to a PC to data log (but you need a serial cable adapter, I scrounged through a junk box at work and found one). And a nice feature is that it has a moving bar at the bottom of the digital display to mimic the swing of an analog needle. So there's a budget level option for you to research that leaves some float.
Whatever meter you end up choosing, try to get one with silicone rubber test leads or at least set aside a few bucks to upgrade to them. Lots of stock meters come with really stiff PVC insulated leads and they are a pain to deal with. I bought a test lead kit made by Probe Master that came with accessory adapters like wire clamps, alligator clips, and spade connectors that has made life easier, especial the wire clamp adapter.
Skip the auto ranging feature, in my opinion. You should know what voltage you are going to measure.
@RoyBoy posted:Skip the auto ranging feature, in my opinion. You should know what voltage you are going to measure.
Amen to that Roy, …..
Pat
My go-to meter is my Simpson 270:
I also have two Harbor Freight digital multimters that I got as gifts ("free with any purchase") for making purchases at HF; they seem to work okay for casual use.
@PRRMP54 posted:My go-to meter is my Simpson 270:
The Simpson 260, 270 family of meters are a classic, gold standard in the VOM world, and certainly ideal for model train use. I use fixed Simpson meters myself to monitor current. Yet the 260 or 270's are not spec'd as true-RMS meters, nor are the Simpson meters I use. In fact, virtually all the Simpsons with analog (needle) meter movements are not spec'd by the manufacturer as true RMS.
I've never seen a true analog meter that measured true-RMS. The analog movement is inherently an averaging measurement. I have heard about thermocouple meters, but I've never encountered one in the wild. 
@gunrunnerjohn posted:My Fluke 117 has pretty much your whole list. I don't have AC/DC auto detection, and I don't want it. Many times I want to measure the DC component of an AC waveform, I don't want the meter deciding for me what mode to be in.
John, It's 'just' a setting from what I'm reading... Fluke 117 - AutoVolt automatic AC/DC voltage selection.
@Dennis-LaRock posted:John, It's 'just' a setting from what I'm reading... Fluke 117 - AutoVolt automatic AC/DC voltage selection.
It's automatic for the LoZ setting, but not for the normal high impedance voltage reading. At least I don't see any way to make it be automatic.
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