I’ve done some work with 2 of those meters over here.

You are going to be extremely disappointed with them. They are not good as standalone data loggers. When connected to a computer they are actually useful. Assuming you are using my scripts which are much more reliable than the junk that comes on the included CD-ROM.

They don’t need very much of a PC. A cheap raspberry pi or 20 year old desktop is more than enough.

For what you are talking about there is only 1 good option out there: an old android phone running the ceiling bounce app.

I bought a new ZTE smartphone from Tracfone for $9.95 for this exact purpose

ChibiM wrote:

9.95? Are you kidding? Wow.

Yeah, they basically give them away in hopes you will use their service. I just checked, and there’s a newer upgraded ZTE for $14.95.

They aren’t bad phones if all you want to do is make phone calls, and txt message. In the US, all phones are required to be able to make emergency calls to 911 whether or not you subscribe to a cell service. So these cheap phones are good for emergency use as well

Not sure how good those meters below $50 will work, but here's what I've been using (about $180).

I've been using a Reed Instruments SD-1128SD (Amazon link) for all my runtime graphs. You can view my runtime graphs by clicking on my J5 or SC700d reviews in my signature. It meets all your requirements (except price) - although it has an RS232 connector for hooking up to a computer and would require a USB/RS232 adapter (I've never used or needed that function). Runtime data is copied to an SD card that you simply pull out and plug into your computer for the basic Excel file. Uses six AA batteries, which I've found gives about 3-4 days of runtime on Eneloops, but I also use the optional wall adapter for long tests.

If you order one of those Aliexpress meters, I would like to know how well they work.

Extech sells a similar meter here:

https://www.amazon.com/Extech-SDL400-

ChibiM wrote:

Tonight another problem. After waiting 3 hours, I noticed the Ceilingbounce app already stopped after 2 hours

I have had the same issue with the Android app I use, but it’s just a quick trip over to the Doze settings (or your OEM equivalent) to make sure it doesn’t happen.
App info > Battery > Battery optimisation on stock Android Q.

M. one can also use smartphone as luxmeter logger. there are apps on playstore. they save the data in a common format (csv or similar) and one can postprocess it on the PC or laptop.

Converting a time stamp hh:mm:ss to a counter starting from 0sec is a common task , 

smartphones have brightness sensors. the light meter is an android app. there are plenty of them called 'light meter' or 'lux meter' on google playstore.

smartphone won't die if it's connected to USB charging (powerbank or wall charger).

I've tried it, works well, convenient "UI" and file management. but sure, a physical light meter is the more robust alternative.

Quote:

so need to figure out how to make that into clear data... starting from 0 minutes. Instead of the hours of the day

I could never figure that out either.  So . . . . .

In my Reed Instruments, I always zero the hours/minutes/seconds just before I start a runtime graph. I have to do this every time I do a runtime, but it only takes seconds once you figure it out. Excel then accepts this as starting at 12:00am.

The Benetech GM1020 is ok if you master installing the driver (the device apparently uses a fake FTDI chip and needs an old driver) and upload the settings (doing this the first time is tricky). Beware: Windows 10 eliminates your driver in more recent versions, so it has to be reinstalled from time to time. And it’s getting harder each time.

Last time I did this I had to deinstall the Win driver and install the old driver before Windows could find the new, non-working one. Disconnecting from the net might work, too.

I can help if anyone wants to take this route. The GM1020 is the only budget meter able to store that many data points.

I wonder if any of these companies would consider doing a group buy for a luxmeter that could log to USB.

I like the idea !

Note that the Reed Instruments does NOT have to be tethered to a computer.  It has a memory card slot - that I remove when done with runtime tests. It also has an optional external power supply that can keep the data logging going for days if necessary (see sample below).  I don't think the Extech has either.  I wonder how long the Extech can run on one 9V battery?  The Reed Instruments uses six AA's.

Just letting you know the pros and cons.

I have the UT382… it can be either of these:

-Completely useless because the drivers are impossible to install on anything running windows 7 or newer.

-After installing the drivers on a W10 machine running a virtual instance of windows XP it works great and can easily export values to excel, you can set minimum/maximum value for start/stop, customize data logging interval and real time monitoring. When I was doing reviews I set up a macro to automatically export the values to my runtime graph on excel and after some quick value touch ups I would have a nice runtime graph in less than 5 minutes.

Downsides are it uses a proprietary port so the meter dies with the cable, and it won’t receive power from USB meaning it will drain your batteries QUICK unless you buy one of those Li-Ion to 9V adapter with usb charging from eBay.

Once past the initial setup it is a breeze to use and export the values to your runtime chart. I’d recommend buying one and try to get the drivers sorted out, worst case scenario you get a light meter with no data log function I contacted UT asking them to update the drivers (they just need to sign them) but received no response.

Will the 1030 connect to a PC for uploading data?

Thanks, so I’ll stick to the 1020.

I'm currently spending some of my spare time on a personal project I've had my sights set on for a while - a standalone runtime test setup based off of the Adafruit TSL2591 light sensor and a Raspberry Pi Zero.

Making it standalone is a bit of a learning experience for someone like myself with little coding skills, but if you want to use it connected to a PC it would be very easy. The sensor and RPi0 together are less than $20, and the rest of the pieces needed to get up and running you probably have in a junk drawer somewhere (microUSB cable, microSD card, some wire).

Edit: If I were going to use this tethered to a PC, I would probably replace the RPi0 with an Arduino Micro or similar.

Arduino is interesting. I did a lot with the Leonardo with its native USB port. You can make it a keyboard to transfer data. And I think there’s a SD shield available. Add LCD and sensor and be done with the hardware.

I’ll be sure to make a post and link to here if it ever gets to a complete state