Terminal boards for WebControl

rossw said:
If you're referring to the terminal board and amplifier module, yes it would let you measure light levels.
Depending on your requirement for precision, accuracy, stability and temperature sensitivity, there are a number of ways to do it.
 
A small PV cell would be easy, with a gain of around 20 would give you 0-10V out.
If you already have a Cds cell (photoresistor), you can connect it in a voltage-divider circuit and use the amplifier to give you a greater voltage swing, but it's difficult to get them linear over a wide light range, and Cds cells have poor temperature stability.
A PIN diode or phototransistor would work too. Perhaps you can give us more information about your needs and intended application?
Click to expand...
 
I want to reliably measure how bright it is outside so I can tell if I should have light be turning on or off inside the house. Some days are dark/dingy/cloud etc. I might also use it to control when porch lights come on toward the end of the day as well.
 
I purchased a few of these: http://www.adafruit.com/products/161
 
Finally, I have experience with some very basic electronics. Nothing with amplifiers or chips on a PCB. Just relays and a once in a rare while a resistor. I also wrote a CQC driver for the Webcontrol so I'm okay with software.
 
So that's where I'm at. I'm going to do some reading and education tonight.
 
bbrendon said:
I want to reliably measure how bright it is outside so I can tell if I should have light be turning on or off inside the house. Some days are dark/dingy/cloud etc. I might also use it to control when porch lights come on toward the end of the day as well.
 
I purchased a few of these: http://www.adafruit.com/products/161
Click to expand...
 
 
OK. Not sure that a Cds cell would have been my first choice, but lets fly with it for now!
 
*IF* you connect the Cds from ground to one of the analog inputs, and a 100K resistor from the analog input to +12V, and IF the Cds cell operates as stated on that site, your input will go from 0.57V (when the cell is in bright light and is only 5K resistance), up to 8V on the input (with the cell has 200K resistance)
 
This should give you PLENTY of range. Amplifier gain is almost irrelevant, unity gain would do, but 1.25 would give you an input from about 0.71V (light) to 10V (dark).
We could swap the light and dark if you want the analog value to show "light" rather than "dark" level :)
 
I will include a couple of 100K resistors with the boar I send you so you can play :)
 
When I build and test the boards, they're calibrated for a gain of around 2, but that's easy to adjust. I'll try to remember to set them to about what you want. (Unity gain is if you turn the pot all the way anticlockwise)
 
FINALLY I have plenty of boards available back in stock now guys.

The batch I was expecting a month ago arrived damaged in transit. Between everyone blaming everyone else, it took a while to sort out - in the end I just had another lot made. They turned up this morning, properly packed and intact.
 
So if anyone is still after any, I can now supply!
I plan to build a bunch and send to a friend in the USA for "local delivery" - should be quicker and cheaper, will advise on that shortly.
 
Details and online ordering etc over here: http://webcontrol.rossw.net/
 
rossw said:
FINALLY I have plenty of boards available back in stock now guys.

The batch I was expecting a month ago arrived damaged in transit. Between everyone blaming everyone else, it took a while to sort out - in the end I just had another lot made. They turned up this morning, properly packed and intact.
 
So if anyone is still after any, I can now supply!
I plan to build a bunch and send to a friend in the USA for "local delivery" - should be quicker and cheaper, will advise on that shortly.
 
Details and online ordering etc over here: http://webcontrol.rossw.net/
Click to expand...
 
Ross: I placed an order today for a bare board and kit with regulator. I'm in the U.S. reference number 9kWL6o. Thanks!
 
Bugman
 
Bugman said:
Ross: I placed an order today for a bare board and kit with regulator. I'm in the U.S. reference number 9kWL6o. Thanks!
Click to expand...
 
Order received, thanks Daniel. It's 10:45pm here, I'll get it in the mail tomorrow morning.
 
Cheers, RossW
 
Bugman said:
Ross: I placed an order today for a bare board and kit with regulator. I'm in the U.S. reference number 9kWL6o. Thanks!
 
Bugman
Click to expand...
 
In error, I soldered an opamp onto the "Plus" board first, then realized my mistake. Consider it a "freebie".
The kit of parts and the "Plus" board with amp chip have gone airmail this morning. Cheers!
 
Hi Ross,
 
Is that possible to add optical isolator IC between the 16 pin connector and TTL input terminals?  The external noise could penetrate the on board TTL input buffer IC causing some experienced lockup. From one user reported, he added optical isolator in front of the TTL input fixed the problem.  Would it possible to add them on the terminal board?
 
CAI_Support said:
Hi Ross,
 
Is that possible to add optical isolator IC between the 16 pin connector and TTL input terminals?  The external noise could penetrate the on board TTL input buffer IC causing some experienced lockup. From one user reported, he added optical isolator in front of the TTL input fixed the problem.  Would it possible to add them on the terminal board?
Click to expand...
 
It would certainly be possible, although even as it stands the terminal board has the option of pullup or pulldown resistors or filter capacitors. (Could equally be diode clamps to limit inputs over 5V).
 
I've got a lot of work on at the moment, but as soon as I can clear a window I'll look at another board version with optoisolators.
 
CAI_Support said:
Any latest update for this IO board?
Click to expand...
 
Been too busy with other work, but also with the (soon to be released) terminal board for the WC32, thought it might be prudent to see how people use it and if it needs any tweeking before "back-adapting" it to the WC8.
 
I just ordered two fully assembled (I am in lazy holiday mood) to Hong Kong.
Looking forward to your WC32 board. If you need somebody to make them for you in China let me know (not me, but I may be able to put you in touch).
 
Hi,
I'm in need of digital potentiometer for voltage control supplying fans. Do you think this may be done using the terminal board and a digital resistor using up and down commands changing the resistance?
Or should I wait for PWM support from WC32?
thanks
 
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