Looking for AC current/power logger - Page 1
Forum section: electronics / testgear

author: Finderbinder
author_rank: Regular Contributor
timestamp: February 16, 2023, 07:44:13 pm
content: There are countless amount of simple devices which logs/counts energy consumed per time unit (day or hour at best). Basically all of them works by the same algorithm as I suspect (they are clones of clones of copies of...).But I didn't see any logging current/power at desired time intervals (ms, s, min).Its purpose would be to understand the specifics of device's work just by looking though trends (not physically sitting by the device and continually watching long process).Device with integrated AC socket for device under test and logging to memory card or USB media also triggering would be the best solution.

author: Tjuurko
author_rank: Regular Contributor
timestamp: February 17, 2023, 10:24:31 am
content: All the power meters I saw issued the measured parameters (U, I, P, F, PF, T) through the serial port (9600 8N1) one time per second.This port can be immediately connected to BLE.The data registrar can be any "Raspberry Pi", she will be binding data to the current time.

author: TomKatt
author_rank: Frequent Contributor
timestamp: February 17, 2023, 11:49:53 am
content: We've got a Fluke 435 Power Monitor at our plant that does that kind of thing. It's a bit ofverypro kit with a price tag to go with it, but you probably don't want to be holding a Uni-T when you're measuring 3 phase feeds with 100's of KW powerBut, same idea.https://www.fluke.com/en-us/product/electrical-testing/power-quality/434-435

author: BILLPOD
author_rank: Frequent Contributor
timestamp: February 17, 2023, 06:43:17 pm
content: Good Morning Finderbinder, there are plenty of multimeters with logging capabilities. The one I use most is the EEVblog121GW, which can log to a micro SD card and the results transferred to a spreadsheet to see trends. Also the sample rate is programmable. Google it and look at it's specifications and you will be impressed. (10 Amp max.)

author: alm
author_rank: Super Contributor
timestamp: February 17, 2023, 08:15:23 pm
content: Quote from: BILLPOD on February 17, 2023, 06:43:17 pmHow do you measure real power (energy consumed per time) using a multimeter? Unless the meter specifically supports measuring real power, like the Gossen Metrahit Energy series. Does the EEVblog121GW support that? I don't mean the apparent power you get from multiplying RMS voltage with RMS current.

author: SerjP
author_rank: Contributor
timestamp: February 17, 2023, 08:37:06 pm
content: UNI-T UT71E multimeter has power measurement function and bundled with power measurement adapter having AC socket. It is able to store data into internal memory but have space for 100 measurements only. So, it is not very useful.Using bundled IR-USB cable it possible to transmit data to PC in real-time. So, it sends 1-2 measurements per second to PC.It is possible to create a Excell script (I've done that) that will store received data in Excell every XX seconds/minutes/hours. Thus, we are getting potentially unlimited "memory depth". Also we can draw charts in Excell (see example below for accumulator charge temperature monitoring, same can be done for power measurements).BTW, UniT is not the top reliable brand, so it all depends on your budget.

author: Finderbinder
author_rank: Regular Contributor
timestamp: February 21, 2023, 04:58:54 pm
content: Quote from: SerjP on February 17, 2023, 08:37:06 pmExactly this model was my main DMM till now and I also have power measurement adapter with AC socket (I use it for immediate power measurement, not for logging)Nice trends. BTW, I can't wire my main DMM for logging, because I use it regularly. I need a dedicated logger, not a chain of devices.However, now I feel deserved a DMM of more serious manufacturerNothing bad about UT71E (good resolution, ruggedness, sleek design, versatility, fast on, acceptable battery usage, many many years of reliable work), just hoping to get some upgrade from new instrument (Fluke? Metra Hit?). Especially I expect fast continuity detection (UT71E, Fluke 75 II are very unacceptably slow in this, totally unusable when tracing multilayer PCBs). I keep otherwise crappy Mastech MY-64 especially for this purpose, it beeps instantly, without any lag - super.

author: Finderbinder
author_rank: Regular Contributor
timestamp: February 21, 2023, 05:17:59 pm
content: Quote from: alm on February 17, 2023, 08:15:23 pmOne may think this smart socket (and countless amount of similar clones) CAN log power usage at chosen time intervals:https://gostation.lv/en/products/teckin-wifi-smart-plug-amazon-alexa-google-home-2/Nice, convenient and smart device but...However it CAN NOT. It (and maybe all it's clones) only accumulates energy consumption per time unit (hour is the smallest one, and you can't change it). It can trigger at chosen power level but it do this VERY unreliably. So it is out of question... unless maybe you can write your own app, because all existent apps do the same: accumulates energy consumption per time unit...