Best value bench top multimeter

[jvm]

Any recommendations for a cost effective bench top meter? Time to upgrade from my portable ECG that I've used since 1994.

[tedmich]

Whats your budget? Does it need to do everything or do you already have a power supply, or LCR or scope?

Also do you want new or used ok?

[jvm]

I mainly just need a good multimeter with AC/DC mV capability. Under a couple hundred dollars if possible. What are the advantages of a true RMS meter? Worth the added cost?

[Randall]

I bought a re-furbed Fluke 77 and I couldn't be happier. IMO a good bench meter is worth every penny. I also upgraded from an old ECG, and there really is no comparison.

[nsubulysses]

When you say bench top I take it you mean a non-portable meter like this.


But maybe I am wrong so I will throw out a "hand-held" style meter like Randall. The best bang for the buck meter that I know of is the Fluke 27/FM. It is a true RMS military grade version of the Fluke 27/II. The military has dumped them now because they now get militarized Fluke 28/IIs instead. They can usually be had on ebay for $30-80 as military surplus. If you want, you can get one with a high voltage probe and carrying case too. I bought 3 because they were so cheap. One has no cal sticker, one was cal'ed by the army in 2008 and the other in 2012. They all read very close together and I would consider them more accurate than my new BK Precision DMM

They are indestructible and waterproof -- Fluke 27 FM Digital Multimeter DMM Tested | eBay

They are very heavy and rugged. They do not fall over when you use the tilt back bailer, and the bailer can be flipped upside down to hang the meter from the wall whcih can be nice in some situations.

Edit: oh yes and they also have 1000 hour battery life. I have left these on overnight by accident a few times and it just really doesn't matter.

[tedmich]

The Fluke 27 FMs on Ebay look good and tough, which is a good thing cause most of them look like they've been "ridden hard and put away wet" as the cow pokes say...

[Tom Phillips]

I mainly just need a good multimeter with AC/DC mV capability. Under a couple hundred dollars if possible...

Given you budget you could get a NIB Fluke 27FM.
See the ebail sale at New in Box Fluke Model 27 FM Multimeter Newest Version | eBay for example.
Nice, new, with accessories and no unknown abuse.
Cheers,
Tom

[Enzo]

Please make it clear what you are shopping for. I also consider a "bench meter" to be the kind that sits on the shelf, not one you carry around. The portable ones like the nice Flukes mentioned above are hand meters.

I have a nice HP bench meter, but I rarely use it. My Fluke can be set anywhere I like, even right on the circuit boasrd, so I can probe points and not have to look up on the shelf to see the reading.

[jvm]

Good to see you here , Enzo! I'm looking for a bench top for sure. I have several hand meters. The $200 range is a ballpark figure. I just don't want to pay for more than I need. One thing I'm not clear on is the true RMS capability. Worth the added cost?

[km6xz]

True RMS is voltage related to heating power of DC at the same numerical value. That means the wave form does not change the accuracy of the RMS reading. That is useful in audio because what is measured is often not a low distortion sinewave. RMS reading meters only display the RMS value accurately when the AC measured is a sinewave. Power output of an amp that is clipping will be accurate with a True RMS meter and it will be inaccurate on a Average reading meter or a Peak reading meter. A Peak reading meter will tend to agree with a scope display.

A bench meter has some advantages, usually more accurate, and less likely to be damaged by abuse. They also frequently have Kelvin measurement capability useful in accurate low resistance measurement. There is a place for both on a bench and few people can get by with only one meter since it is common to have to measure two parameters or more at once. Bench meters often have db calibration as well, very useful in audio measurements. I have lots of bench, lab and a couple hand meter, they all get used, sometimes all at once. My favorite for general work is the common bench Fluke 8050 because it does not have autoranging so measurements are settled faster. It also has selectable reference Z for DB measurements. I got my main one years ago for $450 back when that was a lot of money but now it is $50 on eBay. It has the advantage of running on rechargeable batteries and only uses AC mains when off and charging so ground and line noise is avoided, but the shielding is still grounded.
So my recommendation is getting a bench meter for $50, and a hand meter for about the same. Be sure the meters you select have the voltage ranges you need. For tube get 1000volts DC is a good range. Many smaller meters are 300-600 volts max. My HP 7 digit lab meter is only 300volts. My 6 1/2 digit Phillips PM2525 is 1000v. All my bench Fluke's are 1000 volts but hand held are not. Another important feature if the resistance bias voltage on low ohms or mid ohm scales so it will or will not forward conduct semiconductor junctions. The 8050a on the 2k ohm scale will properly show almost any junction but other meters will not or not forward conduct reliably. That is one reason it get used most often. If you are doing lots of tube gear, an old VTVM is almost bullet proof and reads with just enough accuracy, about 5%, to be very reliable and rugged. The old Heath, RCA and other can be had for a low price. The Heath IM-18 goes for about $25-50 and will never die. For those who want the best, the servo metered HP 410C is great. It has an acorn tube in the AC meter probe that is flat to 700Mhz but almost useless with out that probe. Most on eBay that go for less than$250 are missing that probe for AC. They have the ohms and DC voltage test leads attached. For a lot less money and less modern looking meter, the HP 410B is a bargain and will keep running long after you retire.

[jvm]

Thanks for all the input guys. I have a Energy Concepts 50200A multimeter. Does anyone know if this is a true rms meter? If this will do all I need it to, I'll spend my money on a decent function generator. I also have ECI AC/DC power supply and mosfet analog meter. Any opinions on the quality of this equipment. Worthwhile or should I invest in better?

[g1]

This really depends on the range of equipment types you are going to be working with.
If you're just doing tube stuff, I think you are already there (aside from generator).

[km6xz]

The Energy Concepts 50200A was made specifically to sell at high cost to high school classroom use and is not very good, about the same specs 3.5 digits etc at $19 digital hand meters. Companies who specialize in school supplies and equipment are not very competitive in quality of performance since they only customer is purchasing agents in schools who are easily wined and dined and give orders to specialty companies who cater to them. If it works, it will be OK. It is not true RMS.
A function generator is not an audio signal generator, it is a waveform generator and is used for different purposes. An audio generator has a low distortion sinewave output and sometimes has a square wave output derived from hard clipping of the pure sinewave. A function generator is primarily intended to produce waveforms other than sine waves but uses filters to lower distortion somewhat to 5-10% and the waveform is seldom symmetrical. Function generators square wave output is usually adjustable for DC offset and duty cycle, both needed for the types of uses function generators are put to. They also have triangular wave and sometimes sweep functions and FM modulation. A good audio generator will have calibrated output level and reasonable frequency accuracy. One of the best(for general shop use) is also cheap, the old Heathkit IG-5218 or IG-18. Their output meter is accurate in volts and dbm and dbv, frequency decade switching is accurate, has low distortion, and a wide range of output level from low mic levels(-70db) to 10volts RMS(+22db) with an accurate step attenuator. 1khz Thd is in the 0.016% range but can be modded for even lower.
There are low cost digital generator modules using DDS that are frequency accurate but you need to built your own low z output buffer and calibrated attenuator and some sort of level metering since they have low output voltage and fairly high output Z. Technically they are really nice, low distortion and small, but just not complete test instruments for the bench.
For a little more you can get a used Sound Technology 1700B ultra low distortion generator with built-in auto-nulling distortion analyzer for about $250 and a version that also has IM distortion analyzer for $350. About the only thing lower in distortion is an Audio Precision for MUCH more money. Current models run $28k-35k

The essential items for repair or building amps: Decent scope with 10:1 and maybe an extra 100:1 probes
AC and DC ammeter or multimeter that has high AC sensitivity
8-15amp Variac(metered with both current and voltage meters)
Load resistors configurable to 4, 8 and 16 ohms
Audio signal generator
Controlled temperature solder station.
test amp and monitor speaker
A guitar, any cheapie, to generate realistic signals for listening tests. If you do not have one you can use a CD recorded of a guitar feeding the recorder directly with no amp in the way so the test signal is very close to the signal that a guitar generates so a standard repeatable complex waveform can be amplified and listened to for comparing amps or speakers. You can't play a guitar and be consistent since you can hear the speaker so are inside a system feedback loop. That is the reason when people claim minor differences between some change of type of cap or cable or even tubes, based on their playing, it is never a valid test. You play differently depending on what you hear, which changes your playing, even a slight change in position of your ear in relation to the axis of the speaker will dramatically impact how you play and perceive the sound. Recording a guitar signal without an amp to later feed an amp is called Re-Amping and is very often done in recording studios. A part might be played and then that recording plugged in to various amps or adjustments of effects where chances due solely to the effect or amp can be isolated from playing variables.

A DC current/voltage regulated variable power supply is a nice addition but not essential.
A meter with an effective junction test function for diodes and transistors is helpful but not essential if you have a ohm meter with relatively high open circuit bias voltage set to the 2k range.
High quality connectors on test and jumper cables and adaptor cables. Spend a day wiring connectors in every possible interconnection way you might need, mark them as poisonous, cover in pink shrink tubing or labeled as dangerous so no one will "borrow" them. This is seems so obvious but you would be amazed by the number of commercial shops that do not have the right cables for the job at hand.
A bigger investment will be in spare parts than test gear for an effective hobby or pro repair shop. Compared to other hobbies or businesses the test equipment investment is almost nothing compared to just about all the other fields.

[tedmich]

The BK PRECISION 5491A looks nice and is almost identical to the Agilent U3401A. It looks like the BKs go for <$150 too, any opinions on either of these units?

[ron vogel]

I can't tell you for the above unit, but BK precision quality is very good. I have the 2709b handheld unit from them, and nothing under $300 touches it (and it's just around $100)