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Products => Test Equipment => Topic started by: Drirr on January 25, 2012, 08:47:41 am

Title: Agilent U1231A teardown
Post by: Drirr on January 25, 2012, 08:47:41 am
Hi,
I have decided to make teardown and small review of Agilent U1231A.
U1231A is probably the cheapest 6600 count meter of this kind from Agilet but quality is still excellent.
When you turn this unit on, it starts beeping. This kind of beeping reminds me some oldschool gameboy :-D but you can change it in options menu. This unit is capable of measuring voltage in normal and Zlow mode to avoid ghost volages. AC voltage measurement is true RMS and it is working up to 100KHz . The AC voltage value on 100KHz is not much different from my U3401A unit. Freqency measuring (counter) range is 200KHz and sensitivity on 20KHz is about 30mV and in the same time it is displaying AC voltage on bargraph.  Resolution on ohms range is 0.1ohm and maximum resistance value is 66MOhm. Reaction of continuity testing is fast but when the contact is not good, it makes strange sounds, there should be some delay before buzzer turns off. Diode test is fine, when diode is OK it beeps once so you don't have to watch display. When diode is shorted it is beeping continuously.  Resolution of capacitance mode is 1nF. I have tried compared accuracy of capacitance measuring with APPA703 RLC meter and both show 400nF. On higher capacitance's (like electrolytes) there were some small differences caused by measuring  methods. Other ranges are auxiliary.. some clamp meter and temperature probe, but you have to pay extra to get them.
Accuracy of DC voltage and resistance is fantastic both unit U3401A and U1231A are showing the same value, only on 5V reference the U1231A is jumping between 5.000V and 4.999V .

As I mentioned before there is options menu where you can setup almost everything. You will find it on page 82 http://cp.literature.agilent.com/litweb/pdf/U1231-90026.pdf (http://cp.literature.agilent.com/litweb/pdf/U1231-90026.pdf)

U1231A also have functions like difference hold/log/min/max/avg manual/autorange/ backlight with 3 levels flash light with 7 levels  etc... The flashlight is really powerfull and beam angle is something betwen 10 - 20 degree

On this cheapest unit you can not find Vsense and current range :-(

When you take a look inside you can see that this unit is powered by 4 AAA cells so battery lifetime is about 600hours without backlight (Current consumption I measured is 1,5mA). There is no fuse because there is no current range, but all other ranges are well protected by PTCs and some discharge tubes.  Probe inputs are really tough, there is no way to damage them. Range switch is well protected by rubber bumpers.

Measuring probes are rated CAT IV 600V CAT III 1000V. Insulation on cables is made of PVC and 5000V rated.

Title: Re: Agilent U1231A teardown
Post by: Short Circuit on January 25, 2012, 10:38:22 am
A great benefit of this and other Agilent meters is that they come with calibration certificate. This makes them ideal for ISO9001 work environments (as ISO calls for periodic calibartion of T&M equipment). And the price of this entry model is roughly equal to the cost of calibration of a simple meter. So simply buy a new one each year and give away the old one.

Good that you bothered to read the manual, the power on beep is very annoying. (Imho proof of Chinese design ~ non-functional bells&whistles, they love that.)
Also increased the power off timer from 15 minutes to 60 minutes, much better.
Title: Re: Agilent U1231A teardown
Post by: saturation on January 25, 2012, 10:50:27 am
Thanks for sharing.  Looks very well made indeed, a good competitor for a similar model Fluke.
Title: Re: Agilent U1231A teardown
Post by: bongiovi on January 25, 2012, 11:36:15 am
A great benefit of this and other Agilent meters is that they come with calibration certificate. This makes them ideal for ISO9001 work environments (as ISO calls for periodic calibartion of T&M equipment). And the price of this entry model is roughly equal to the cost of calibration of a simple meter. So simply buy a new one each year and give away the old one.

Good that you bothered to read the manual, the power on beep is very annoying. (Imho proof of Chinese design ~ non-functional bells&whistles, they love that.)
Also increased the power off timer from 15 minutes to 60 minutes, much better.

Chinese?  Agilent is from China?
Title: Re: Agilent U1231A teardown
Post by: nanofrog on January 25, 2012, 11:53:27 am
Agilent bought out Escort Instruments in order to have an affordable handheld product line, which were, and I suspect still are, designed in Taiwan. Manufacturing is done in Malaysia.
Title: Re: Agilent U1231A teardown
Post by: EEVblog on January 25, 2012, 12:29:55 pm
Agilent bought out Escort Instruments in order to have an affordable handheld product line, which were, and I suspect still are, designed in Taiwan. Manufacturing is done in Malaysia.

Agilent told me all their handheld design groups (Formally Escort) engineering is done in Malaysia, and is now a fully integrated part of Agilent.

Dave.
Title: Re: Agilent U1231A teardown
Post by: Short Circuit on January 25, 2012, 12:52:53 pm
Chinese?  Agilent is from China?
No not really, but quite likely designed by Chinese anyway;

Quote
Malaysian Chinese are a well-established middle class group of people. Like much of Southeast Asia, Malaysian Chinese are dominant in both the Malaysian business and commerce sectors and are one of the biggest taxpayers contributing to almost 90% of the nations income tax.
http://en.wikipedia.org/wiki/Malaysian_Chinese (http://en.wikipedia.org/wiki/Malaysian_Chinese)

Assuming EE is a middle class job, there's 90% chance the design is done by a Chinese fellow  ;D
Title: Re: Agilent U1231A teardown
Post by: DavidDLC on January 25, 2012, 10:31:17 pm
Agilent bought out Escort Instruments in order to have an affordable handheld product line, which were, and I suspect still are, designed in Taiwan. Manufacturing is done in Malaysia.

Agilent told me all their handheld design groups (Formally Escort) engineering is done in Malaysia, and is now a fully integrated part of Agilent.

Dave.

True, I'm working on a problem I found on the U1232B with an Applications Engineer on the USA, but the actual engineering group checking the problem is on Malaysia.

Seems like the multimeter does not have enough filtering for the DC voltmeter part of it.

Title: Re: Agilent U1231A teardown
Post by: nanofrog on January 26, 2012, 02:48:53 am
Agilent told me all their handheld design groups (Formally Escort) engineering is done in Malaysia, and is now a fully integrated part of Agilent.
Interesting.

I'd have thought they would have kept it in Taiwan where Escort was based at the time Agilent came calling. Cost reasons maybe? Or dare I dream, actually put the designers in or near the manufacturing facility so they can have physical access to a product from design to order fulfilment by intent?
Title: Re: Agilent U1231A teardown
Post by: bongiovi on January 26, 2012, 10:27:16 am
Chinese?  Agilent is from China?
No not really, but quite likely designed by Chinese anyway;

Quote
Malaysian Chinese are a well-established middle class group of people. Like much of Southeast Asia, Malaysian Chinese are dominant in both the Malaysian business and commerce sectors and are one of the biggest taxpayers contributing to almost 90% of the nations income tax.
http://en.wikipedia.org/wiki/Malaysian_Chinese (http://en.wikipedia.org/wiki/Malaysian_Chinese)

Assuming EE is a middle class job, there's 90% chance the design is done by a Chinese fellow  ;D

Yeah, it's does seem right.  All the non-functional bells and whistle indeed.

But I've been using HP/Agilent scopes for decades (made in America, I assume), and the SW and HW interface hasn't changed much.  From the old 54622 to the 5000 series, to the recent 2024 that I purchased, it felt like just a skin on top of the old.  Well, to be fair, the 2024 changed quite a bit, but many things are still the same.

Comparing this with Rhode's new scopes (made in Germany?), now that's something fresh.

Chinese - gimmicks
American - same old same old
German - in between ?

Haha. 
Title: Re: Agilent U1231A teardown
Post by: Bored@Work on January 26, 2012, 12:19:20 pm
But I've been using HP/Agilent scopes for decades (made in America, I assume),

They "always" had instruments made in other countries, too. E.g. in the '60th they had a thing going on with Yokogawa in Tokio. And until recently their entry-level oscilloscopes were rebadged Rigols.

Quote
Comparing this with Rhode's new scopes (made in Germany?), now that's something fresh.

R&S does oscilloscope manufacturing in some Eastern European country. Dave has a video from an exhibition where some R&S guy mentioned this. Although I am not sure if this was just for the Hameg line or the new  RTO line.

Quote
Chinese - gimmicks
Cheap, entry level stuff. Quality issues, some companies seem to be willing to learn, others don't. Good enough for a lot of simpler tasks.

Quote
American - same old same old
Some companies start to get it. E.g. Agilent with their 2000 and 3000 series made steps in the right direction. But most companies will just die a slow death, clinging to and waving the American flag while they go down. Those in the killing-people business will likely survive, based on government spending.

Quote
German - in between ?
Not really on the map any more. Some traditional companies that manage to hang on and do innovative stuff now and then, but no new innovative measurement companies.

This is a world where you have to pilot a speed boat, not a slow old rusty tanker. And the Chinese are almost the only ones having speedboats in the water, and a lot of them, while countries like the US or Germany have slow, hard to maneuver, sometimes very rusty tankers in the water. The Chinese speed boats are running rings around them. Although the Chinese speed boats are made from bubblegum and don't have live vests on board.
[/quote]
Title: Re: Agilent U1231A teardown
Post by: nukie on January 26, 2012, 01:07:36 pm
Malaysian Chinese might be blood related to people from China but they are totally different breed. If they are the same, the tax office would be built out of recycled cardboards.

Chinese?  Agilent is from China?
No not really, but quite likely designed by Chinese anyway;

Quote
Malaysian Chinese are a well-established middle class group of people. Like much of Southeast Asia, Malaysian Chinese are dominant in both the Malaysian business and commerce sectors and are one of the biggest taxpayers contributing to almost 90% of the nations income tax.
http://en.wikipedia.org/wiki/Malaysian_Chinese (http://en.wikipedia.org/wiki/Malaysian_Chinese)

Assuming EE is a middle class job, there's 90% chance the design is done by a Chinese fellow  ;D
Title: Re: Agilent U1231A teardown
Post by: PetrosA on January 27, 2012, 03:00:07 am
Agilent HH is in one of those special economic zones in Malaysia which I suspect makes doing business more cost effective.
Title: Re: Agilent U1231A teardown
Post by: poorchava on August 21, 2012, 09:23:29 pm
Sorry for thread-gravedigging.

I'm looking around for a new multimeter. Currently using UNI-T UT71A (has some annoying quirks, but overall quite functional).

I can't justify putting out $600 for a Fluke - IMO those are overpriced even if you take quality and brand name into account.

Are you happy with this Agilent? It can be had for like $140 from Farnell which makes it kind of the same proce as UT71A. It has lower display range (6k vs uni-t's 20k) but probably Agilent is more accurate and you can get actual support should anything go wrong. Any comments?

Does anyone else have possiblity of comparing this one to U1232A, U1233A, U1241B, U1242B? Which of those represents best value for money in your opinion?
 
Title: Re: Agilent U1231A teardown
Post by: Short Circuit on August 21, 2012, 10:38:35 pm
I would not recommend the U1231 as your main DMM;
The autoranging is rather slow, which can be annoying when doing everyday measurements.
When used as second DMM, this is often less of a problem.

Here's a quick compare of U1231A against Fluke 189 showing the autoranging in action
DMM Autorange (https://www.youtube.com/watch?v=k-YAdTq0jhY#ws)
Title: Re: Agilent U1231A teardown
Post by: retiredcaps on August 22, 2012, 05:02:59 am
I can't justify putting out $600 for a Fluke - IMO those are overpriced even if you take quality and brand name into account.

What model costs $600 in your country?
Title: Re: Agilent U1231A teardown
Post by: Drirr on August 22, 2012, 06:13:58 am
@ Short Circuit

But did you consider price difference between U1231A and Fluke 189 ?
Title: Re: Agilent U1231A teardown
Post by: poorchava on August 22, 2012, 08:59:06 am
I can't justify putting out $600 for a Fluke - IMO those are overpriced even if you take quality and brand name into account.

What model costs $600 in your country?

Seems like I was mistaken, the bloody site displays net prices when you're not logged on and gross prices when you log on. The gross price as shown below is PLN 2263 ($692). That would be even harder to justify
Screenshot from http://www.tme.eu/en/ (http://www.tme.eu/en/)
(http://img38.imageshack.us/img38/5314/clipboard01eef.jpg)
Title: Re: Agilent U1231A teardown
Post by: Short Circuit on August 22, 2012, 09:28:58 am
@ Short Circuit

But did you consider price difference between U1231A and Fluke 189 ?
That is not relevant, only tried to illustrate that the U1231A autorange could be a little too slow for comfort.
BTW I also have a low-end Fluke (Model 16 I think, not sure where it is), and I never got attended to it's autoranging, meaning it's probably as quick as this highend Fluke.
Title: Re: Agilent U1231A teardown
Post by: retiredcaps on August 22, 2012, 09:24:04 pm
The gross price as shown below is PLN 2263 ($692).

I'm not a Fluke fanboy, but comparing a Fluke 87V to an Agilent U1231A isn't an "apples to apples" comparison.

If you are interested in the U123X line, then you should compare it to the Fluke 114-117 models.

And of course, Dave did a review of the Fluke 117.

www.youtube.com/watch?v=3k9nVg03Wi4 (https://www.youtube.com/watch?v=3k9nVg03Wi4#ws)

PS. I managed to get one Fluke 117 for $28 CDN and another for $50 CDN with patience and some good luck.
Title: Re: Agilent U1231A teardown
Post by: Short Circuit on August 22, 2012, 10:15:39 pm
vs Fluke 16 (which is exactly same intended use and price class, except 10-15 years older )
DMM Autorange (https://www.youtube.com/watch?v=d0viDtfdNxk#ws)
Title: Re: Agilent U1231A teardown
Post by: ilikepez on August 23, 2012, 08:55:42 pm
If I was in the market for a small meter I would give the Agilent a hard look. The price is very good and the feature set is great. I think the ability to add a bluetooth module and monitor it with your android device is huge in my opinion, and Fluke is lagging behind severely in those areas.

The auto-ranging speed really doesn't put me off too much. Sure it would be nicer if that was faster but considering what else you get its minor.

Hopefully Agilent will open up the code used to communicate with the U1177A and some cool android apps will be made using that.

It might give Fluke a little kick in the butt too.
Title: Re: Agilent U1231A teardown
Post by: M. AndrĂ¡s on August 23, 2012, 09:12:24 pm
I can't justify putting out $600 for a Fluke - IMO those are overpriced even if you take quality and brand name into account.

What model costs $600 in your country?

Seems like I was mistaken, the bloody site displays net prices when you're not logged on and gross prices when you log on. The gross price as shown below is PLN 2263 ($692). That would be even harder to justify
Screenshot from http://www.tme.eu/en/ (http://www.tme.eu/en/)
(http://img38.imageshack.us/img38/5314/clipboard01eef.jpg)

if you have time and you search in my topics you can find some numbers on that how much my fluke 289 kit cost me, i posted some numbers on how much is the price different between here in hungary and in the usa, just a quick number on it. it was 18xk huf and i get 100k salary every month :). no i dont work in a field where i can use it. its just for my selfish purposes for now and for later times i hope the damn corporation will buy decent gear and i dont have to use my stuffs at work. you can do the maths if you want the current usd/huf rate is 220huf=1usd. if you use it a good gear will pay for itself in reasonable time. i dont aim this for fluke products. its for quality products in general,
Title: Re: Agilent U1231A teardown
Post by: FenderBender on December 07, 2012, 02:09:41 am
Here comes the thread grave-digger....

I think I might purchase a U1232A. I'm really interesting in getting a PC datalogger, because I think seeing data visually in tables or graphs helps me debug or understand a circuit better.

$190 with the bluetooth adapter...(My PC is not at my workbench, but about 30 feet away.)

I've got a whole bunch of things on the "buy for self for Christmas list" and I'm liking the looks of one.

Of course...It's definitely not an electronics oriented meter. It's accuracy is rated between 0.5% and 1.9%, which are not too impressive. But, I'm not sending a rover to Mars here, so a digit or two off isn't a big deal.
Title: Re: Agilent U1231A teardown
Post by: T4P on December 07, 2012, 10:47:08 am
Let's face it ... the fluke 117 costs 180$ (179 costs about 100$ more) doesn't have even a mV or a uA scale  :palm:
Though the omission of a mA scale on the 1232 is abit odd ... Funny thing is they both have similar or rather EXACT specs  :o
Title: Re: Agilent U1231A teardown
Post by: FenderBender on December 07, 2012, 11:32:35 pm
Yeah that's the only real problem I see. It goes from 600uA to 6A. Accuracy is rated the same on both scales, but I do not know what resolution you would get on the 6A scale. It's a 6000 count meter. What's the maximum amount of digits I'd get if I was measuring say 0.5A?

Also it seems the 600uA range is unfused. Is there a particular reason for this? High impedance something? Idk

Title: Re: Agilent U1231A teardown
Post by: alm on December 07, 2012, 11:45:36 pm
I don't own this particular meter, but a 6000 count meter on the 6A scale would display 0.500 A.

I believe the uA scale is sometimes used by HVAC techs, that's probably why it's there instead of the (for an electrician) not very important mA scale. The 600 uA could have a high enough impedance that electronic protection circuits are enough, what's the rated input voltage and over voltage category according to Agilent? I would tend to trust their specs.
Title: Re: Agilent U1231A teardown
Post by: FenderBender on December 08, 2012, 02:49:14 am
Hmm interesting. I guess the problem would be if you tried to measure 5mA? Youd only get one digit? No?

It's CAT III 600V.

Found a picture of the board for reference:

(http://sigrok.org/w/images/thumb/6/62/Agilent_U1232A_PCB_bottom.jpg/800px-Agilent_U1232A_PCB_bottom.jpg)
Title: Re: Agilent U1231A teardown
Post by: alm on December 08, 2012, 11:26:54 am
For 5 mA, the reading would be 0.005 A +/- 0.003 A (accurcy spec). The data sheet also mentions a very odd gap between 0.6 and 1.0 uA.
Title: Re: Agilent U1231A teardown
Post by: FenderBender on December 08, 2012, 05:21:18 pm
For 5 mA, the reading would be 0.005 A +/- 0.003 A (accurcy spec). The data sheet also mentions a very odd gap between 0.6 and 1.0 uA.

Well that's not too impressive. Then again, this is clearly an electricians meter.
Title: Re: Agilent U1231A teardown
Post by: nctnico on December 09, 2013, 09:11:57 pm
Today I got my new U1241B to replace my >20 year old portable DMM. I choose the U1241B because it was about the cheapest A-brand DMM which can show 1mA resolution when in 10A mode (or 10V with 1mV resolution) on a 10000 count display. Not that I expect it to be that accurate but at least I can see what I'm doing when adjusting something. The first impression is not bad although the beep of the continuity tester is a bit slow but not the slowest I ever encountered. When the volt measurement is selected it defaults to AC but that can be changed in the setup menu (hold shift while turning the DMM on).