Can you spend under $10 USD and get a Clamp meter that works? - Page 1
Forum section: electronics / testgear

author: beanflying
author_rank: Super Contributor
timestamp: January 11, 2019, 01:51:48 am
content: YESSo I ordered this Lemon coloured MT87 to dismember and use in a little project but I thought I would try out the clamp meter part of it that I will be scrapping. Delivered from a dodgy evilbay seller 'claiming' to be in Sydney but as expected was out of China (Tax GST Fraud anyone) for about $8.50 USD to the door.DUT 3 Group Izzo Lever Coffee machine. Should be drawing 13A or so in its current (pun sorry) 2 of 3 element leg configuration. Fairly Pure inductive load as I had unplugged the 0.37kW Pump Motor.As a multimeter it is a joke, fixed ranges all round. So a 5VDC reference got me 004 on the display for a 20% error. Measured a 250Resistor got me 00.2 for an error of 20% againI haven't dropped the covers off but there is no way in !@@$ing Hell I am probing near mains with it so assume it will kill you dead.Photos for the data but the MT87 did surprisingly well against the UT210E. Andif you don't own a clamp meter of any sort then worth adding to the kit.Not much good for really low currents but for around the house not to bad.Feel free to add your own disasters and bottom of the barrel clamp meters here too

author: beanflying
author_rank: Super Contributor
timestamp: January 11, 2019, 02:15:14 am
content: For completeness here is the internals. It actually has 'some' protection still not using the 'Cat III 1000V' probes it came with

author: tsman
author_rank: Frequent Contributor
timestamp: January 11, 2019, 02:44:48 am
content: The most bizarre part is that your MT87 is the cost reduced version. Somebodymodded a MT87 with a nRF radiobut their unit is far more complicated inside. Enough people buy this MT87 that it was worth designing an even simpler + cheaper version.What are you intending to do with your one?

author: beanflying
author_rank: Super Contributor
timestamp: January 11, 2019, 02:55:10 am
content: Nothing as fancy as thatI am stripping it down to just a DC voltmeter running a lithium primary cell to power it. Overkill really but I am then putting it across the terminals of a Cap Discharger to avoid having the inputs of my just arrived expensive LCR tweezers going pop. Much over 3V for them is a no no. Could have been done other ways but this way gets me a few hundred volt input side.

author: tautech
author_rank: Super Contributor
timestamp: January 11, 2019, 04:21:18 am
content: Now you have a decent AWG....and presumably a decent DSO, sweep it to find its BW.

author: cdev
author_rank: Super Contributor
timestamp: January 11, 2019, 04:22:40 am
content: Does that mod look like it may still be compatible?I have a UT210E and I love it. And dumping data from it seems to be figured out.But $9 sounds like a much better price than $30 for something that doesn't need much resolution that I would plan to - like you, take apart.So that this cost-reduced one could be used as a real time power monitor for an entire house? (with a 200 amp service) similarly to the modded older one?

author: beanflying
author_rank: Super Contributor
timestamp: January 11, 2019, 04:33:07 am
content: To late to play bandwidth games switch is bridged with solder and the clamp is in the bits bin alreadyAC only unlike the 210 (love it too)I have one of these yet to be played witheBay auction: #132702915152but I sort of bypassed it and have used a few Sonoff POW's for power monitoring and switching via WiFi instead. There is some options for new firmware for proper logging of power (TASMOTA is one) for the Sonoff's too.