[SOLVED] Request for advice on circuit-design of multimeter: Peaktech 3360

[tim343]

Hello all,

I watched Mr Jones 50+ minutes blog on multimeter buying advice. Since I found it pretty interesting I already upped my budget to around 100 dollars.

I'm considering buying a Peaktech 3360 (good availability in Europe), since it seems to have a good 10A fuse. I'm worried though, that it might have a bad circuit design (seems important according to Mr Jones).

Please check out the following picture (click on it to zoom) and be so kind to give some advice if it is total shit or not.
http://www.mikrocontroller.net/topic/200782

I also considered the Amprobe 37XR, but the slow continuity test seemed like a no go.

See the following link, If you are interested in technical details of Peaktech 3360
http://www.peaktech.de/productdetail/kategorie/digital---handmultimeter/produkt/p-3360.html

Thank you

btw: I'm a beginner who wants to temper with automotive electronics,  the occasional 230V and maybe checking small electronics devices.

[Bored@Work]

The PeakTech is a rebadged CEM multimeter. The PCB indicates a DT-9919.  http://www.cem-hh.com/en/product3.php Not surprising, because AFAIK this PeakTech company does not manufacture any own products.

Interestingly, the price on eBay for an original DT-9919 is rather inflated, $229.98.

The image shows mediocre build quality. There is something going on with the parts making up the input protection. There are unpopulated footprints, and it appears the populated components don't fit exactly. But it is difficult to say if they left out originally planned protection components or if they mounted different ones.  There is also some bodge job with resistors above the upper fuse in the image. And the lower glass fuse is not to my liking.

Other stuff looks nice, e.g. it looks as if the case is well sealed, screws on the terminals, double isolated wire from the amp com terminal (but it touches the fuse holder, not so nice). The ES51966 is one of the many multimeter ICs from Cryustek. Their stuff can be found in many Asian meters. And in principle their ICs work, although I have the feeling they exaggerate their specs a little bit too much. The firmware seems to be in an Atmel atmega32 MCU. This gives the potential for some hacks, especially if they haven't protected the firmware. If they have the protection fuses activated it might not be worse it. At least there seems to be a programming header on the board.

But there is one general thing. Those Asian manufacturers do change things on the fly and some have rather varying manufacturing quality. So the meter you might get might be different from the one in the picture.

[tim343]

Thank you very much for your quick feedback. I'll check through the rest of Mr Jones budget multimeter related blogs, but I'll propably end up buying the Peaktech 3360 since you seem to indicate that I could do worse for the money.
The only avaible alternative, Uni-T multimeters, seem to have nice specs (they advertise a 0-delay continuity test function) but Mr Jones seems to think the build quality is a load of crap. Also they seem to have no good 10A fuse.

Thank you

[david77]

I haven't laid hands on the 3360 yet but I can say a few things about its smaller sibling the 3320.
Both are made by CEM as BAW has already said, Peaktech have quite a few of their meters in their program.

In my opinion the CEM made meters are the better ones that Peaktech sell, some of their stuff is quite nasty and cheap.
The cases are nice and quite rugged, the rubber parts are molded on. The tilting stand things are usually quite shit, I guess they are on most cheapish meters. Switches are OK, there are many that are far worse.

I can't say much about accuracy or the design of the electronics, although I have some doubts about the input protection. I had a 3320 returned that had allegedly been connected to 230VAC mains while set to the cap range. I don't know if that was what really happened, though. My default setting is to distrust customers. It was toast but Peaktech did exchange it without a problem. May be the circuitry on the 3360 is better, who knows?

Apart from that and user caused defects we haven't had issues with Peaktech's products.
Would I buy one for myself? No, probably not.

[T4P]

Thank you very much for your quick feedback. I'll check through the rest of Mr Jones budget multimeter related blogs, but I'll propably end up buying the Peaktech 3360 since you seem to indicate that I could do worse for the money.
The only avaible alternative, Uni-T multimeters, seem to have nice specs (they advertise a 0-delay continuity test function) but Mr Jones seems to think the build quality is a load of crap. Also they seem to have no good 10A fuse.

Thank you

Huh ? Get the UT61E , those ceramic fuses are decent , can handle 8kA interuptting current .
The UT61E is available from 55USD , you can also change the fuses to HRC if you want , because there are HRC footprints on the pcb .

[mc]

I'm a beginner who wants to temper with automotive electronics,  the occasional 230V and maybe checking small electronics devices.

Given your planned use, I'd say you're possibly overthinking this.
Fair enough if you're needing something highly accurate, research for the best you can afford, but for the uses you've described, something reasonable accurate is all that's needed.
For automotive use, the main thing you need is a reasonably accurate voltmeter. Ohmeter is only occasionally used, but normally on components that have a relatively wide tolerance, and only time you really need an ammeter is for checking current drain.

At home, I'm currently back to my cheap £15 meter after my good one got a bit too close and personal with a digger, and it ticks all the boxes. Might not be the most accurate, but it's accurate enough for automotive diagnosis, with the odd bit of mains and electronic work.

I do have a PeakTech something or other for use at work, and it's certainly good enough quality for being bounced around cars/trucks, and has all the required features for normal automotive use, along with the occasional mains/electronics repair.

[Bored@Work]

For automotive use, the main thing you need is a reasonably accurate voltmeter. Ohmeter is only occasionally used,

That reminds me of something, or, as our host would call it "a trap for the young player". Do not measure resistance of something in a car unless you are absolutely sure where you connect to. Sticking the ohmmeter on some unknown wire might accidentally trigger an airbag in the car. And modern cars have a lot of them.

[tim343]

Thanks for the additional input. I might actually buy a UT61E from dx for 60 Dollars and get myself a BK2909 (? well the one reviewed by Mr. Jones) when I'm making a trip to the USA some time this year.

Its to bad that the continuity test of the UT61e performed quite slow in Mr. Jones review. Since the continuity test might be one of the most useful functions for me right now (when dealing with low voltage), I would propably be better of with a cheap 20 Dollar DMM with a quick continuity test.

Its hard to find reviews of such cheap DMM though. The advantage would be that they leave me enough money to buy a decent one later.

[Bored@Work]

I consider the Uni-T stuff a joke. Just because you could re-add the protection circuitry and proper fuses Uni-Trend seems to skip theses days doesn't mean it is a serious and safe meter.

The thing people keep recommending Uni-T junk is because they bought it, and can't admit they bought crap.

[saturation]

I would second Board's comments on Uni-T.  If you are looking for a DMM but are cash strapped, get a used US made Fluke.  The 27 series often sells for <$50, its a rugged basic DMM and it won't disappoint.  For details, search on excavortee's name and read his write up of used Flukes. 

Its not as desirable compared to the 80 or 70 series because it only has basic functions, but 90% of the time, that's all you need and because its not loaded, IIRC 9V battery life is in 1000s of hours.  Its was a common US military DMM in its heyday.
 
http://www.ebay.com/itm/FLUKE-27-FM-MULTIMETER-/330711333141?pt=LH_DefaultDomain_0&hash=item4cffee7915

[Lightages]

I have three UNI-T meters. The UT33C at $17, UT10A at $14, and a UT71E at $170. I would be happy to buy another UT10A or a UT33C, but never would I spend that kind of money on anything UniTrend again. Maybe I might buy a UT61E based on what I have seen here but I would always be questioning the accuracy of what I was reading and that is never a good thing with a multimeter.

[T4P]

Thanks for the additional input. I might actually buy a UT61E from dx for 60 Dollars and get myself a BK2909 (? well the one reviewed by Mr. Jones) when I'm making a trip to the USA some time this year.

Its to bad that the continuity test of the UT61e performed quite slow in Mr. Jones review. Since the continuity test might be one of the most useful functions for me right now (when dealing with low voltage), I would propably be better of with a cheap 20 Dollar DMM with a quick continuity test.

Its hard to find reviews of such cheap DMM though. The advantage would be that they leave me enough money to buy a decent one later.

That's the UT61D , there's a sharp difference between the two of them . Jones reviewed the UT61D

[bfritz]

I'm not sure how availability is in Europe, but here in the US, a local sales site like Craigslist has lots of people selling older generations of Fluke multimeters, at very good prices.  I can usually pick up some of the older case styles of a Fluke 77 for about $65 US.  Used can be a very good deal, especially when you end up getting a quality meter like a Fluke.

I wouldn't be too worried about calibration.  I bought a Fluke 77 when I was in college in the mid 80's, and I recently checked to see if it was still in calibration.  It was still in the middle of the calibration range.  If you buy a quality meter that looks decent on the outside, it will probably be fine on the inside.  If you are buying it in person, look at the manual before you travel to pick it up, and determine how to test the fuses.  Usually you can use the probes and the meter itself to test the fuses in the meter.  I also usually bring a battery and known resistor, So that I can test voltage measurement, resistance measurement, and current measurement. (Connect battery and R in series, and complete the circuit with the meter.)

Anyway, don't make the mistake of assuming new is better.  Often, Good quality used test equipment, can be as inexpensive or less expensive than cheap new equipment.

[retiredcaps]

I can usually pick up some of the older case styles of a Fluke 77 for about $65 US.  Used can be a very good deal, especially when you end up getting a quality meter like a Fluke.

I have no affiliation with the seller, but saw this and would purchase it myself, but I can't justify another multimeter right now.  Excavatoree will have no competition from me.

Used Fluke 83V for $69.99 + $5 for shipping to USA.

http://www.ebay.com/itm/170820251731

Let's see how long this auction lasts after my post.  It has probably not been bought right away because of the Easter holidays?

[mechelec]

I have the Amprobe 37xra and would highly recomend it.
If you check one of the earliest eevblog videos you will find Dave has done a favourable review on it also.
While it's true the continuity function is painfully slow I have found if you use the logic tester to check continuity you get a much better result.
In fact It appears to be as good as any Fluke, at least I can't fool it by tapping the leads together.

[tim343]

Well thanks for so much input. I really tried to read up on multimeters before posting here, but I found your advice way more specific to my future needs and thus very helpful.

The used fluke solution might be just what I was looking for, since I really don't need TRMS but rather a solid DMM to check out higher voltages without unneccessary risk. Also having a Min/Max was a must for my future 50-100 Dollar DMM.

With a used fluke, I might even get an Autohold function, which I think is really useful. This was out of my price range before. Also accuracy isn't too important to me, since I was considering buying only a cheap DMM, before having first seen one of Mr. Jones DMM related blogs. Now I'm way more conscious about possible safety hazards.

Well since I'm pretty sure a used fluke (I would have never considered buying a used DMM before ) might be the ideal solution for me, I want to thank you all again for the good advice.

I'll still be checking this thread and report when I finally made my purchase (maybe wihtin the next 3 months). But i'll propably not reply to this thread anymore unless something major comes up.

Thanks