I just picked up some new solar panels and I'd like to confirm they pull in as much current as they are supposed to. I know I can just run some device like a motor off of them and see what the current draw is using a multimeter but I'm curious if there is some way to measure the panels actual generated current.
I'm looking for some kind of device (like an ammeter) but if it's simple enough to build a circuit to do this using an off the shelf IC that's fine too.
Thanks for any help.
I'd go with the ammeter; ready-built, no calibration issues. Cheap too
But if you want to log or manipulate data using an arduino then use a hall sensor with 0-5 volt output for the current range you're interested in. Note that you can "decrease" the range of a hall device by looping the current lead through the sensor more than once. For example, if you have a 0-25 amp sensor and you loop the current lead 5 times through the sensor aperture it effectively measures 0-5 amps.
jack
I've used this before and it works great and is pretty cheap
http://www.devicecraft.com/haefcuse1.html
At that price it's the obvious choice. I surmise you'll be wanting to monitor up to around 20 amps so for the 80 amp unit you could simply loop one of the feeder cables through the doughnut 4 times to maximise resolution.
jack
Im using this:
http://www.panucatt.com/files/datasheets/cs50_100_200a_datasheet.pdf
working flawlessly since then.
cheers
tomasi:
Im using this:http://www.panucatt.com/files/datasheets/cs50_100_200a_datasheet.pdf
working flawlessly since then.
cheers
Thanks Tomasi, but the pdf has been moved here.
some interest on this site for Devicecraft's current sensors. They appear to output either dc or ac depending on what you're measuring. I want to measure AC. How do I read an AC voltage with an arduino? I also may try to use an Iobridge to do this, it has a 0-5 volt analog input. Any suggestions? we want to measure every appliance in the house,so they need to be relatively cheap.
By it works with ac is that it responds fast enough so you can measure the current during the cycle and find the rms current with calculation, I haven't done it yet but I imagine it can't be hard
Solar panels put out AC now? Or you are looking at the inverter output?
For every appliance, I would get a Kill-A-Watt.
Plug it into the wall, plug your device into it.
Available at Radio Shack even.
We got one from our local library, then went & bought our own.
Forgot to mention the devicecraft puts out a ratiometric output so at 0 amps it reads1/2 vcc (2.5v usually) and at +80its at 5v(vcc) and at -80 its at 0v(vss), so you would be reading an entirely positive signal that refers to both a positive and negative current flow with the use of an offset
Most ICs for this purpose are surface mount as they are newish. ACS711/712/713 series springs to mind here.
Yeah I own a couple of the Allegro devices, Easy to solder to a piece of PCB material and 3 to 6 dollars on Ebay. Since I am only interested in discharge or load current, I built a small Op-Amp level shifter so I could have a scalable Power Supply Monitor.
Doc