Cheap USB analog interface?

Define cheap ;)

The HoBo stuff does usb wireless.

I have not seen a small ADC --> USB logger that's cheap. Would be useful tho. I've done a PIC USB HID and its not that difficult.

Cheers

d.

Not cheap, but quick and dirty. I have a PIC connected to an Android phone with the camera pointing to the meter. The phone can push images to any web site. The PIC is running on isolated solar power and is going to sample the V & I, as well as pushing excess power back into the meter.

Hard to sample V & I with javascript. You need Assembler or C on a micro.

Quarter wave samplings should be good enough to give you some idea of power consumptions.

You can always go with a USB host uC and USB WiFi adapter. However, software for WiFi adapter is not simple.

That would require a TPC/IP stack, or maybe just UDP.

Here's a Dataq logger for $29

You just need a wireless interface.

Cheers

t t t

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o 9.95$ cheap enough? code is be simple enough to change if you rather it be a "normal" usb device instead of simulating a keyboard

rather than going all the trouble of getting a usb host to talk to a wifi module, I'd get something like this:

10004 looks straight forward to get it running: ic.php?f=3D32&t=3D25129

-Lasse

What National Instruments is not.

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You probably need to have at least a laptop (USB host) to hook this up, and you need to power it separately from the main. With lower power host uC, it's easier to isolate the power. To sample full wave, you need to tie the uC with one of the hot wire (220V). I am just going to sample and inject quarter wave (first quadrant), so my uC ground is tied to neutral. I am using 250V 3A opto isolated power injectors.

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nope, that last link was for someone who used a arduino, (8 bit avr) and about one page of c code to transmit the on time of an input pin

-Lasse

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Don't you need a laptop or USB host controller to receive the data?

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Mine is 100% open:

Not cheap, though, because it does 16 channels over ethernet. Adapt as you see fit :-)

Well, mine uses current clamps, so if you're not wanting to open your breaker panel, it's not for you. If you use clip-on sensors, you don't need to disconnect the wires, but those are bigger and more expensive than the feed-through types.

The ADE power metering chips do all that for you - power factor, watts vs volt-amps, power, energy, etc. Just add a current clamp, an AC voltage (for phase reference), and something that talks SPI. These are the same chips that are used in digital side-of-house energy meters.

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you'd want a computer somewhere to recieve the data sent over wifi, othervise theres not much point in sending it ;)

other that as far as I can tell that code and avr+WiFly combo will connect to a wifi network and start sending data to a fixed ip

-Lasse

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I'm not sure I understand what you are talking about

the mcu and that wifi module sends the data over wifi, you can connect that to mains if you want to. The only connecting to the outside world is wireless thats' kinda the point of using wifi

But some where in the world something has to receive that data, that could be your desktop, a web server somewhere etc.

-Lasse

I thought we are talking about this USB interface.

Wireless USB

Which one? Any link?

Its kind of funny that a few years ago, Wireless USB was the rage.

Today the usb.org has changed the Wireless USB to a "good idea":

PCs have Bluetooth or 802.11 as standard wireless interfaces.

802.15.4 (Zigbee) seems to be a custom solution, but lots of people are making them.

So, there is really no wireless standard that's cheap.

hamilton

Or reliable enough. I guess it's OK for the OP, since he is only interested in monitoring the line. However, my goal is to inject power at the proper phase angle. If it's off, it could be getting 300V

• voltage mismatch. So, i don't really trust USB (wired or wireless) in the control loop.

d.

one: (928)428-4073

Possible inspiration here ...

Monitor

-- Cheers, James Arthur