NEW ANENG AN882B+ ??? - Page 1
Forum section: electronics / testgear

author: 001
author_rank: Super Contributor
timestamp: September 23, 2018, 11:21:08 pm
content: Is some new version here?

author: Fungus
author_rank: Super Contributor
timestamp: September 24, 2018, 01:32:01 am
content: Looks like a new one.No MIN/MAX/REL?Ohms/diode/continuity/capacitance all crammed into a single range? That doesn't sound like much fun.I'll stick with the 860B+.

author: mtdoc
author_rank: Super Contributor
timestamp: September 24, 2018, 02:52:48 am
content: From the display it looks like it does have MIN/MAX and REL

author: Fungus
author_rank: Super Contributor
timestamp: September 24, 2018, 02:57:43 am
content: Quote from: mtdoc on September 24, 2018, 02:52:48 amThat doesn't mean anything. They use the same display in all their meters.

author: Johnboy
author_rank: Regular Contributor
timestamp: September 24, 2018, 08:08:12 pm
content: This looks sort of like a redesigned ZT102, with a uA range. I looked at the current Zotek models and none of them seem to match exactly.

author: 001
author_rank: Super Contributor
timestamp: September 25, 2018, 10:20:37 pm
content: Quote from: Johnboy on September 24, 2018, 08:08:12 pmWHY?

author: HKJ
author_rank: Super Contributor
timestamp: October 12, 2018, 09:32:28 am
content: I have been looking at the meter (Review will show up at a later date), but I will post a warning here:mA range is protected with a 200mA PTC, not very smart for a 600mA range.10A range is unfused, even though the front says fused.The enclosure says it uses a 9V battery, but it uses 2xAAA.

author: umbro
author_rank: Contributor
timestamp: October 12, 2018, 09:56:19 am
content: WTFalmost empty case.

author: Fungus
author_rank: Super Contributor
timestamp: October 12, 2018, 01:32:39 pm
content: Quote from: HKJ on October 12, 2018, 09:32:28 amNot necessarily bad for protection (it will heat up much faster if it's underrated) but it will cause big burden voltages as you go higher.Quote from: HKJ on October 12, 2018, 09:32:28 amThe fuses are the probe cables.Joking aside: This is not good. I guess even ANENG has trouble producing meters at this price. This is only slightly better than an 830B.The bad part is that it could damage their reputation for $20 meters (which are quite good).Quote from: umbro on October 12, 2018, 09:56:19 amNot looked inside many multimeters...?

author: HKJ
author_rank: Super Contributor
timestamp: October 12, 2018, 01:34:43 pm
content: Quote from: Fungus on October 12, 2018, 01:32:39 pmIt will heat up too fast to measure 600mA

author: umbro
author_rank: Contributor
timestamp: October 12, 2018, 02:08:07 pm
content: Not looked inside many multimeters...?About 10 Different multimeters

author: HKJ
author_rank: Super Contributor
timestamp: October 12, 2018, 02:16:07 pm
content: Quote from: umbro on October 12, 2018, 02:08:07 pmYou are are interested in the inside of multimeters you can just check my review list:https://lygte-info.dk/info/DMMReviews.htmlIt is more than 70 multimeters now, both cheap and expensive.

author: umbro
author_rank: Contributor
timestamp: October 12, 2018, 02:45:07 pm
content: I have visited your website often, nice work

author: Fungus
author_rank: Super Contributor
timestamp: October 12, 2018, 05:01:47 pm
content: Quote from: HKJ on October 12, 2018, 01:34:43 pmIt should take several seconds to heat up, but... yeah. Not good for a multimeter. You couldn't leave it connected while you're working on something.Maybe you can measure the time needed to heat up and/or plot a graph of burden voltage against time as part of your review.(also: don't PTCs have a limited number of cycles before they die?)

author: rsjsouza
author_rank: Super Contributor
timestamp: October 12, 2018, 05:20:06 pm
content: Quote from: 001 on September 23, 2018, 11:21:08 pmIt certainly looks so. Although... Yawn. Pretty boring meter IMO.Quote from: umbro on October 12, 2018, 09:56:19 amIt may be theHarbor Freighteffect...

author: umbro
author_rank: Contributor
timestamp: October 12, 2018, 05:55:21 pm
content: Quote from: rsjsouza on October 12, 2018, 05:20:06 pmSpot on

author: HKJ
author_rank: Super Contributor
timestamp: October 12, 2018, 06:01:07 pm
content: Quote from: Fungus on October 12, 2018, 05:01:47 pmFairly easy to do:First one is 400mASecond one is 600mAIn addition to a high burden voltage you also got a strict time limit.I would not worry about any limit on PTC cycles, it depends on how serious out overload it and I doubt it would have much affect with low voltage, maybe mains voltage would add some wear.

author: floobydust
author_rank: Super Contributor
timestamp: October 12, 2018, 06:29:46 pm
content: There's plenty of room in there for decent fuses, but oops it's under the display...PTC fuses fatigue after the first few trips, their holding current drops quite a bit. It would be good to trip it say 5 times and then do the test. I wonder about its voltage rating, only telecom PTC's good to high voltage but they are much larger than this one. Think about the holding current+voltage and all the heat generated.What is the pushbutton switch (pads) for on the backside? CAL mode perhaps.

author: HKJ
author_rank: Super Contributor
timestamp: October 12, 2018, 06:50:14 pm
content: Quote from: floobydust on October 12, 2018, 06:29:46 pmPTC are sometimes used as temperature sensors, the change will depend on how hard they are over driven and what they are designed for.I doubt a small over current will add much wear to the PTC.Quote from: floobydust on October 12, 2018, 06:29:46 pmI would expect it to be a button that is used together with one or two of the front buttons to activate calibration, maybe the REL or RANGE button. As you can tell I did not check it.My reviews are not about uncovering all the secrets in a multimeter (or any product), this is much better done in a thread here. I am satisfied if I can describe the behaviour of the meter in a way that means people buying it knows what they get.

author: Fungus
author_rank: Super Contributor
timestamp: October 12, 2018, 07:03:48 pm
content: Quote from: HKJ on October 12, 2018, 06:01:07 pmYou get over two seconds to take the reading - plenty of time!

author: Fungus
author_rank: Super Contributor
timestamp: October 12, 2018, 07:09:19 pm
content: PS: And how long to cool down again?eg. If you switch to 10mA, how long before the burden voltage returns close to zero?

author: rsjsouza
author_rank: Super Contributor
timestamp: October 12, 2018, 07:29:37 pm
content: Quote from: Fungus on October 12, 2018, 07:03:48 pmFacepalm indeed... somehow I think that Zotek (Aneng's ODM) is starting to randomly throw PTCs around the board to see what is EEVBlog's forum folks think of that. If something sticks, then it must be good. First it was the puny PTC near the main IC (AN8008, 8009, 860, 870) and now is on the mA range. What's next?

author: floobydust
author_rank: Super Contributor
timestamp: October 12, 2018, 07:29:54 pm
content: Quote from: HKJ on October 12, 2018, 06:50:14 pm"When there is an overload condition, the polymer heats up internally from I2R heating. When the polymer heats up to approximately 100-125°C, its molecular structure changes from semi-crystalline to amorphous. This causes a macroscopic expansion, which breaks the conductive paths. When the conductive paths are broken there is a large increase in resistance - typically several orders of magnitude. At this point, the device is in the “tripped state”. Upon cooling, the polymer reforms to its semicrystallized state and the conductive pathways are reestablished.However, when the polymer recrystallizes it does not return immediately to the same base resistance. It does not compact as tightly as when it was pre-tripped, and therefore the post trip resistance is typically 50 % higher then the initial resistance.Note the post trip resistance increase is not a cumulative effect; additional tripping will not cause increases in resistance in excess of the first trip."https://www.bourns.com/resources/technical-library/library-documents/multifuse-pptc-resettable-fuses-technical-libraryI did extensive testing on PTC fuses and found they change after the first (few) trips, so I had to factor that into my designs.Here, the 600mA trip might go to 500mA and be very annoying.

author: HKJ
author_rank: Super Contributor
timestamp: October 12, 2018, 07:44:56 pm
content: Quote from: Fungus on October 12, 2018, 07:09:19 pmAbout 10 seconds, at least if I switches to 10mA fairly fast.

author: HKJ
author_rank: Super Contributor
timestamp: October 12, 2018, 07:51:02 pm
content: Quote from: rsjsouza on October 12, 2018, 07:29:37 pmIt is nothing new with PTC's as current fuses, Mastech has been using it for a long time and I have also seen it in some pocket meters, but usual the PTC is selected to match the current range.The small PTC's in meters works fine and will usual handle mains voltage on ohms range, but not much more (Like CAT over voltage). Most cheap meters also has a small 900kOhm resistor that would have trouble with much above mains voltage.