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Products => Test Equipment => Topic started by: helloworld922 on December 12, 2012, 08:06:50 pm

Title: Amprobe AM-240 vs. Extech MN36
Post by: helloworld922 on December 12, 2012, 08:06:50 pm
So I'm thinking of getting a relatively cheap multi-meter that's still functional. I watched Dave's $50 Multimeter Shootout video which reviews the AM-220 which is very similar to the AM-240, which as far as I can tell the only difference is that the AM-240 has temperature capabilities.

I also found the Extech MN-36 which appears to be similar to the Extech EX330 Dave reviewed, though there are a variety of differences:

1. No Non-contact voltage detector
2. CAT-II 600V rating instead of CAT-III 600V
3. Max Frequency measurement of 5 MHz instead of 40 MHz
4. Max capacitance measurement of 100uF instead of 200uF
5. Slightly smaller/lighter

I am able to get either of these meters for around the $35 range (Amazon: Extech MN-36 (http://www.amazon.com/Extech-MN36-Digital-Mini-MultiMeter/dp/B0012VYKVQ/ref=wl_it_dp_o_pC_S_nC?ie=UTF8&colid=I9GNUZGW18EV&coliid=IDDZ15UZR69WV), Zorotools: AmProbe AM-240 (http://www.zorotools.com/g/Compact%20Digital%20Multimeter/00030028/))

What I intend to do:

1. Mostly home hobby-level electronics, I'm usually interested in battery powered or low-voltage type electronics work. Very rarely I might work with mains (120V), though I don't have any plans to do so in the near future. I love sensors and mechatronic-type circuits
2. The K-Type thermocouple (or other built-in temperature sensor) is a must.

Any suggestions on which of these two probes I should go with? Personally I'm leaning towards the MN-36 because it does have 1 pF capacitance resolution vs. the 10pF resolution of the AM-240, but there datasheet/manual does not specify any tolerances at this range.

Oh, and FYI I also found the Extech EX430 (http://www.amazon.com/Extech-EX430-Autoranging-Multimeter-Capacitance/dp/B0000WU1AC/ref=sr_1_4?ie=UTF8&qid=1355342642&sr=8-4&keywords=extech) for $55, which is currently outside my the price range but does have true RMS and a bunch of other goodies.
Title: Re: Amprobe AM-240 vs. Extech MN36
Post by: retiredcaps on December 12, 2012, 11:41:35 pm
Oh, and FYI I also found the Extech EX430 (http://www.amazon.com/Extech-EX430-Autoranging-Multimeter-Capacitance/dp/B0000WU1AC/ref=sr_1_4?ie=UTF8&qid=1355342642&sr=8-4&keywords=extech) for $55, which is currently outside my the price range but does have true RMS and a bunch of other goodies.

I only comment on what I have used or own and even then my experiences with a sample size of one may not be representative.

The Extech 430 overshoots on all readings.  A lot.  For example, when measuring a simple 9V DC battery, it will display 18.11, then 9.01, then 9.00, then 8.99.  This takes about 1 to 2 seconds before a stable reading is found.

I'm not sure if I'm explaining this correctly, but the Extech 430 AC V mode also goes crazy/fluctuates wildly and never stops in presence of > 10V DC.

Again, your experience may differ from mine.
Title: Re: Amprobe AM-240 vs. Extech MN36
Post by: FenderBender on December 13, 2012, 02:09:10 am
I have an AM-220. It's a solid meter. It won't give you any trouble.

Can't speak for the Extechs. I don't have any. But the AM-220 is a good cheap meter. Probably a little overpriced, but not too bad.

I haven't compared this meter with any others, but the AM-510 might be worth a shot:

http://www.amazon.com/Amprobe-AM-510-Commercial-Residential-Non-Contact/dp/B007FZFTZO/ref=sr_1_1?s=hi&ie=UTF8&qid=1355364664&sr=1-1&keywords=amprobe+am-510 (http://www.amazon.com/Amprobe-AM-510-Commercial-Residential-Non-Contact/dp/B007FZFTZO/ref=sr_1_1?s=hi&ie=UTF8&qid=1355364664&sr=1-1&keywords=amprobe+am-510)
Title: Re: Amprobe AM-240 vs. Extech MN36
Post by: helloworld922 on December 13, 2012, 05:44:28 am
Quote
The Extech 430 overshoots on all readings.  A lot.  For example, when measuring a simple 9V DC battery, it will display 18.11, then 9.01, then 9.00, then 8.99.  This takes about 1 to 2 seconds before a stable reading is found.

Yeah, I noticed Dave's review of the EX330 had similar problems with overshoot, I suspect I might end up with the same problem if I choose an Extech.

Quote
I haven't compared this meter with any others, but the AM-510 might be worth a shot

Not a bad looking meter, though I really want a meter with temperature measurement capabilities so I might consider the AM-520 (http://www.zorotools.com/g/00107469/k-AM-520/).

Comparing a few of the AM-520 specs with the AM-240:

1. AM-520 can measure up to the 1kV range vs. 600V for the AM-240

2. AM-240 has 0.5A/250V and 10A/250V fuses while AM-520 is spec'd with 0.5A/1000V and 11A/1000V fast fuses.

3. Better temperature resolution for the AM-520 (0.1C vs. 1C), [-40C,1000C] range for AM-520, [-50C, 700C] range for the AM-240, better accuracy for the AM-520

4. Separate mA/uA and V jacks for the AM-520

5. AM-520 has a non-contact voltage detector

6. AM-520 has a flashlight on it (not just a backlight, an actual flashlight)

7. AM-520 comes with a velco strap

8. The AM-520 supposedly has some sort of bar-graph display for fast changing signals

9. AM-240 can measure duty cycle, I don't think the AM-520 has this capability

10. The AM-520 uses a 9V battery, while the AM-240 uses 2 AA batteries.

As far as price goes, the AM-520 is about $5 more expensive than the AM-240 so it's pretty tempting.
Title: Re: Amprobe AM-240 vs. Extech MN36
Post by: FenderBender on December 13, 2012, 11:11:39 pm
It's a pretty good meter for the price. That's where Amprobe succeeds. Not always the absolute best for electronics work, but it's a good value.
Title: Re: Amprobe AM-240 vs. Extech MN36
Post by: dr_p on December 14, 2012, 12:44:11 pm
The AM-530 got a teardown right here:
https://www.eevblog.com/forum/reviews/amprobe-am-530-a-peek-under-the-hood/msg164418/#msg164418 (https://www.eevblog.com/forum/reviews/amprobe-am-530-a-peek-under-the-hood/msg164418/#msg164418)