Recommended Bench Multimeter - Page 1
Forum section: electronics / general

author: richcj10
author_rank: Unknown
timestamp: October 18, 2012, 09:47:31 pm
content: i do a lot of code writing and circuit testing.I am tired of having to turn on my FLUKE 179 meter every 30 minutes.I was looking into a bench top meter so I can leave it on while I am doing other things.I looked at Rigol DMM's and they are too pricey (cost more than my o-scope)Any recommendations? I would like to stay in the sub 300 dollar level.I also would like to measure temp's with this device as well.

author: retiredcaps
author_rank: Super Contributor
timestamp: October 18, 2012, 10:13:21 pm
content: Quote from: richcj10 on October 18, 2012, 09:47:31 pmIf you don't mind buying new 9V batteries, you can disable automatic power down, by holding the yellow button when powering on.

author: EEVblog
author_rank: Unknown
timestamp: October 19, 2012, 12:11:35 am
content: The Agilent 3478A is an excellent buy on ebay.Dave.

author: Smokey
author_rank: Super Contributor
timestamp: October 19, 2012, 01:25:05 am
content: How much do you think it would cost to send a 3478A out for cal? Would that offset the good price from ebay? As a general question, what have all you meter collectors found the stability of these 25 year old meter to be? Do they mostly keep working well till they die, or do they drift substantially?3478A manual first printing = 1983second printing = 1988

author: richcj10
author_rank: Unknown
timestamp: October 19, 2012, 01:27:33 am
content: Thanks for your responses!I will look into the HP 3478!Thanks Dave!

author: nctnico
author_rank: Super Contributor
timestamp: October 19, 2012, 01:32:04 am
content: I have a Vichy VC8145 which is pretty neat. 4.5 digits (or more), backlit display which is easy to read from all angles unlike reflective LCD displays and its mains powered. They cost less than $200 on Ebay.

author: poodyp
author_rank: Regular Contributor
timestamp: October 19, 2012, 01:34:06 am
content: For $300 you could even snag a 3457.I just bought a 3478 for $180 with calibration.

author: grenert
author_rank: Frequent Contributor
timestamp: October 19, 2012, 05:58:17 am
content: Two things that bugged me about the 3478A:1. There is no zero function! Want to zero the lead resistance on your two-wire ohms measurement? Tough luck!2. Calibration can be done for 2-wire ohms or 4-wire ohms, not both. If you calibrate using 2-wire ohms, your 4-wire measurements will be low. If you calibrate with 4-wire, your 2-wire measurements are high.For the great, great majority of uses, however, it is a fine, highly accurate and stable meter.

author: saturation
author_rank: Super Contributor
timestamp: October 19, 2012, 02:43:22 pm
content: If you don't need amps, the HP 3456a is very well regarded by many, and is built like a tank. You can find lots of discussions in the archives. Prices can range from $60-$300 delivered via eBay, low final price depends on your bid skills. I have 3 working nonstop for 2+ years, 4th died last year but I haven't the time to do the repairs [ failure points are very well known, its typically filter caps on the PSU board.]

author: Unknown
author_rank: Unknown
timestamp: October 19, 2012, 03:41:29 pm
content: I bought myself a Solartron 7150; they are pretty cheap on Ebay!

author: Excavatoree
author_rank: Frequent Contributor
timestamp: October 19, 2012, 05:15:27 pm
content: Quote from: Smokey on October 19, 2012, 01:25:05 amI can't speak about bench meters, as the one I have was adjusted by the seller when I bought it two years ago.I have had 25+ year old Fluke handhelds that haven't drifted much at all - the cal sticker is still in place from 20 years or more ago. My experience has been a good meter that is undamaged won't drift much. I've seen military meters with the last cal date 20+ years ago that were still in spec, and I doubt they were touched since commissioning.

author: benemorius
author_rank: Regular Contributor
timestamp: October 19, 2012, 06:09:15 pm
content: I've picked up a few 3478s on ebay for $100 or so each. They've all been in spec except the one with a dead battery and the oldest cal sticker is dated about 20 years ago so I'm pretty happy with them. That's a tiny sample size of course but I think you'll find similar sentiments elsewhere on the web. I think it's a great way to go if you have another meter to check it against. There are three varieties with cosmetic differences, if you care about that sort of thing. Also they often come with missing feet. You may or may not care about that depending on where it's going to live.In addition to the other complaints that were mentioned, the 3478 also lacks a continuity buzzer as well as diode testing. With a budget of $300, you can just about grab a 34401 on ebay. It has both of those functions plus a few others including an rs232 port. The going price for one in great condition is $400 and up, but you can snag one for under $300 if you're patient and willing to take one that isn't perfect - even less if you don't mind fixing it. Dim displays are common and easy to replace. Someone starting selling new displays on ebay for about $100 a few months ago and they don't appear to be running out any time soon. I don't think they're oem, but I've bought two and I have no complaints about them at all.

author: nctnico
author_rank: Super Contributor
timestamp: October 20, 2012, 12:39:13 am
content: Just beware that the current measurement range on these old HP DMMs is limited to 2A or 3A. The DMM I mentioned earlier can handle 20A. Unless you need high accuracy those old HP DMMs just don't match up with new Chinese DMMs regarding features.

author: reagle
author_rank: Unknown
timestamp: October 20, 2012, 07:15:43 pm
content: HP 3478, Fluke 8840, 8842, Fluke 45s. The first three would be under $100

author: Unknown
author_rank: Unknown
timestamp: October 20, 2012, 08:15:28 pm
content: The HP 3468A/B is sometimes substantially cheaper than the 3478A, but with almost identical features (the 3478A has GPIB, one lower DCV/R range and slightly better accuracy). The lack of zero function and the non-backlit reflective display with poor viewing angle are the main downsides in my opinion.If you don't mind the size, the HP 3455a, 3456a and 3457a are well regarded. Only the 3457a has current measurement ranges, but the 3455a and 3456a have LED displays that are much nicer to read than those annoying unbacklit LCDs. Calibration would be expensive since these require manual trimmer adjustment, requiring a calibration tech to do actual work beyond hooking it up to a calibrator and pressing start.Many of the older bench meters (before late eighties models) lack convenience features like diode test and continuity. Note that ACV/ACI was optional on the Fluke 8840/8842, and that the options check marks on the back are not always accurate. Other interesting models may be the Keithley 199/196. The 199 has similar features as the Fluke 8840/8842 and HP 3468a/3478a. It does have a zero function, and a large high-contrast LED display. You can sometimes find them for well under $100. The 196 has more features, is 6.5 digits, but rarer and often more expensive. The HP/Agilent 34401a is from a later generation with more features. A very similar instrument is the Keithley 2000. Both have nice VFDs that provide good contrast if they didn't get dim from being turned on 24/7 for many years. Finding them for under $300 might be hard, especially if you want calibration included.Newer instruments are often cheaper to calibrate, but more digits tends to be more expensive since it requires more expensive equipment. Be careful with meters sold with calibration certificate. Unless the calibration is performed before shipment, the certificate may be old by the time the instrument gets sold. If the calibration is not traceable to national standards labs and performed to factory specs, then they may have used any old calibrator and twiddled some knobs to adjust the instrument to whatever voltage the calibrator put out. They should have no problem providing you with a sample certificate providing the equipment used for calibration, their serial numbers, and calibration dates.

author: nctnico
author_rank: Super Contributor
timestamp: October 20, 2012, 10:46:45 pm
content: If you are into old HP DMMs be sure to include the HP3466A. Besides LED readout it has a small form-factor case with a handle / tilt stand. Only adjusting the mains voltage is a bit of a challenge because it requires soldering wires inside the case.

author: Unknown
author_rank: Unknown
timestamp: October 20, 2012, 11:44:23 pm
content: Note that some multimeters from the mid-eighties had 300 V upper limits, as opposed to the 1000 V limit of many earlier and later designs. This includes the HP 3468/3478/3457.If you don't care about high resolution/accuracy, then there are a number of cheaper 3.5/4.5 digit bench meters. On the used market, there are the Fluke 8600, 8800, the already mentioned HP 3466a, and the Keithley 175a (the -a version includes backlight). Important criteria might be auto-ranging, display and functions. I wouldn't touch the cheap new 3.5/4.5 digit bench meters (eg. the one with plenty of space to carry your lunch by Uni-T), they appear to be crap.

author: prestigetest
author_rank: Regular Contributor
timestamp: October 23, 2012, 04:42:15 pm
content: I have 2 Agilent 437B unit's available. $385 each and I will calibrate them prior to shipping. I also have Agilent 8481H, 8481D with 11708A attenuator, and 8482A power sensor's to go with them too.

author: T4P
author_rank: Super Contributor
timestamp: October 29, 2012, 08:41:05 am
content: Quote from: Smokey on October 19, 2012, 01:25:05 amThe most stable bench DMMs in the world, in fact the 3457 versions are used to calibrate the calibrators, go figure.