zanydroid
Solar Wizard
That's why it's for rednecks. They don't have better things to do.
Or you can use it as a learning opportunity to level up on computer vision.
Cheap voltage and frequency logger?
- Thread starter wheisenburg
- Start date
Or you can use it as a learning opportunity to level up on computer vision.
wheisenburg
Independent Solar Consultant
I have to admit that I'm rather surprised that there isn't a frequency logger available somewhere for a reasonable price. I did find one device, but it only logged voltage.
The electrical engineer and channel EEVBlog is pretty much dedicated to stuff like this
Why not look at scopes he's had that are handhelds and says are "not bad"
You want handheld ones or what?
I'd guess a bench one would be better if you wanted to log the stuff into a computer CSV or something
Why not look at scopes he's had that are handhelds and says are "not bad"
Recommend budget oscilloscope Please - Page 1
Recommend budget oscilloscope Please - Page 1
www.eevblog.com
You want handheld ones or what?
I'd guess a bench one would be better if you wanted to log the stuff into a computer CSV or something
In oscilloscope they have X amount of memory and that is how long they will "record". It doesn't go to actual storage in the handhelds at least
bench ones can log a lot longer as they have more hardware
also good to know:
An Oscilloscope with an 8-bit ADC has a resolution of 3.125 mV (800 mV/256 Q levels), while a 10-bit ADC has 0.781 mV.
If you are wanting to log for LONG periods of time you are gonna have to get one that dumps info into an actual computer probably.. Otherwise looking at a hefty penny
wheisenburg
Independent Solar Consultant
I'm not sure what the definition of "Long Time" is but I might consider a bench scope since there is so much more you do with one compare to just a frequency logger. Presumably they would make the "logged" values available over a serial connection. I DO know computers and AC electricity a lot better than low level electronics. I'm a computer professional, an electricity armature, and an electronics newbie.
zanydroid
Solar Wizard
It doesn't exist as an accessory for some generic data acquisition widget?
Factor it out, as the cool software engineering kids say.
I don't think we asked- what issues are you having with ac coupling
Yeah, I read all the way through to find out "why". Would like to know more.
zanydroid
Solar Wizard
I'm pretty sure OP has a few megathreads on their equipment problems, I guess they'll link one shortly.
Yea on those forums you can find good ones. Also lots of good used ones on ebay if you want to save some money.
Just get a decent one that can interface with a computer easily and you're set. Almost none of them have that long term multi day logging, so sending it to a computer is the best. I assume that's what you'd want, is multi day
wheisenburg
Independent Solar Consultant
I built a PV Shedding Controller. Right now it uses 25 amp 2 pole contactors to switch strings of PV on and off in order to maintain the SOC at an acceptable level when I am detached from the grid. It seems to be working great. I just had to turn the AC Coupled Mode off on the Schneider.
When AC coupled is on the Schneider will work fine with one string attached, but as soon as a second string turns on ALL the PV shuts down. It won't start again unless you power cycle the PV strings. I would like to be able to see if I can get the AC Coupled frequency / watts curtailment to work. Oh and too work without shutting the PV down completely. I have some ideas on what I might need to do. I might still use my controller, but it would mainly need to shut down the PV only when the power first failed and the SOC was very high. Eventually, the Frequency / Watts should be able to manage the SOC.
I would like to see a graph of what is actually going on with the AC frequency. Real time data would be better then nothing. Enphase used to have High Resolution Data where you could see a graph of the Frequency as well as other data (voltage, watts, current on L1, L2). Not anymore. They removed the feature. I have changed some of my setting and I want to do more testing, but it has been cloudy here. Maybe tomorrow.
Building a PV Shedding Controller for AC Coupled Solar
Back Ground I have an Enphase system with 35*350 watt panels. It uses the IQ8+ micro inverters at 295 watts each. So the total possible output is 10,325 watts. The actual maximum output is about 9000 watts. I have 7 panels that face east and 28 that face west. The slope of my roof is about...
diysolarforum.com
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wheisenburg
Independent Solar Consultant
I think being able to have a fairly detailed view of 10-15 minutes would probably work for me.
What's your budget?
If you want to build one you can go https://www.amazon.com/JYE-DSO-13801K-Open-Source/dp/B00WAQGGZA
Rigol DS1054Z is generally one of the recommended beginner scopes
Sigrok is one of the best softwares, I personally wouldn't buy an oscilloscope unless it was compatible with it. Because the default software for most of the scopes SUCKS ASS I'm sure you're familiar with that kinda crap in the solar world too lol
Rigol DS1000Z series - sigrok
You can log forever with that pretty much
The Rigols have good "recording points" not sure how that'd translate into minutes but honestly viewing anything more than 10 seconds on a scope itself kinda sucks, computer is way better
another benefit of the rigol DS1054Z and the sigrok is there are thousands of youtube tutorials etc so you can get started pretty easily
reading frequency of an outlet and such is a good place to start
These might be worth it to you too, no idea how their computer software is though
Here's another similar thread on the subject
all scopes will be able to read your voltage/frequency you want to do. That's like the very basics of a scope so I can't imagine even 1 exists that can't do that.
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wpns
Solar Joules are catch and release
What’s the resolution/accuracy/precision of all these solutions? I mean I can make a frequency counter read line grequency down to 1mHz if you don’t mind a 17-hour gate time. 
wpns
Solar Joules are catch and release
Now that I'm at my desk I can report that I'm using a https://www.digikey.com/en/products/detail/rohm-semiconductor/BM1Z002FJ-EVK-002/12675573 zero-crossing detector (IC Evaluation kit) and a Raspberry Pi Pico with a 4-digit 7-segment display. Basically count clock cycles between edges and do a little math, so I'm updating the display every second. [And our grid is all over the place, I get emails with subject lines like "Grid Frequency is 58.7 Hz at 2024/03/28 19:21:31" from a Raspberry Pi with a https://ctlsys.com/support/wattnode-modbus-wide-range/ interface, which only checks every 10 seconds!]. I'm very interested in a dual-channel device that can monitor the grid and my mostly-off-grid-unless-I-need-to-use-my-chargeverters EG4 ESS output.
thats interesting! I wonder why it would shut down when more ac coupled pv comes online. I wonder if its exceeding the charging current capabiilty of the xw?I built a PV Shedding Controller. Right now it uses 25 amp 2 pole contactors to switch strings of PV on and off in order to maintain the SOC at an acceptable level when I am detached from the grid. It seems to be working great. I just had to turn the AC Coupled Mode off on the Schneider.
When AC coupled is on the Schneider will work fine with one string attached, but as soon as a second string turns on ALL the PV shuts down. It won't start again unless you power cycle the PV strings. I would like to be able to see if I can get the AC Coupled frequency / watts curtailment to work. Oh and too work without shutting the PV down completely. I have some ideas on what I might need to do. I might still use my controller, but it would mainly need to shut down the PV only when the power first failed and the SOC was very high. Eventually, the Frequency / Watts should be able to manage the SOC.
I would like to see a graph of what is actually going on with the AC frequency. Real time data would be better then nothing. Enphase used to have High Resolution Data where you could see a graph of the Frequency as well as other data (voltage, watts, current on L1, L2). Not anymore. They removed the feature. I have changed some of my setting and I want to do more testing, but it has been cloudy here. Maybe tomorrow.
Building a PV Shedding Controller for AC Coupled Solar
Back Ground I have an Enphase system with 35*350 watt panels. It uses the IQ8+ micro inverters at 295 watts each. So the total possible output is 10,325 watts. The actual maximum output is about 9000 watts. I have 7 panels that face east and 28 that face west. The slope of my roof is about...
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wheisenburg
Independent Solar Consultant
I made major progress on my AC Coupled issues today. Just looking at the Frequency in the Insight Screen seemed to be good enough.
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