Swordfish

very nice!

I'm impressed also especially with the use of the FSR's, nice and compact...

Thanks yo2lio for the great library.

I had used SHT75 before for my application and I find that the chip has severe RH accuracy problems. I had abandoned the idea of using this chip for any or my application.

I had compared the reading of a few units of this sensor with a few calibrated thermohygrometers and the result is a big difference in RH reading at different RH values.

The temperature reading is accurate.

This sensor is also very sensitive to chemical exposure. Your RH reading will drift with time if exposed to chemicals.

Apart from using it in weather station projects, I do not find this chip good for any industrial application. Even then, the RH reading is not accurate.

This is my personal experience to share with others.

Hansolo

I read your note about the Sensirion SHT75..

had used SHT75 before for my application and I find that the chip has severe RH accuracy problems. I had abandoned the idea of using this chip for any or my application.

What Humidity sensor(s) would you suggest as a better alternative?

Jay

You can try using wet and dry bulb method using DS18B20 as the temperature sensors.

Alternatively you can try using HIH4000 from Honeywell.

Hansolo

Hansolo..

Thanks for the suggestion.

Jay

I use now 6 sensors SHT11 and I don't have 2 sensors with the same result !!!??? +- 10 % accuracy.

I used in the past HIH3605 and works very good (sensor is sensible at light).

Also I use Wet bulb / Dry bulb , works great but is very sensible at high air velocity.

I've been looking to acquire some parts for a project I have in mind, and it requires taking a trio of temperatures, and a humidity reading.

Sometime ago, I was given a Sensirion SHT-75, and I had some Dallas DS18S20's from a Kits 'r Us gadget.

I'm far from actually being ready to design and program the actual project; in fact I just took the plunge and purchased an EasyPIC4 and the Swordfish Basic Compiler. (Thanks xor !)

I'm trying to follow some sound advice, and walk before I run, so I'm attempting to get an LED to blink! (Good advice, Thanks gramo !)

Withe the modules for the Dallas 1-Wire temperature sensor, and the code done for the Sensition SHT-xx units, I thought all was well until I read about other users's opinion and experiences with the SHT sensors. Thanks hansolo and yo2lio !)

While I'll probably start off with using the SHT-75 to help with the learning process, in the end I'll follow hansolo's suggestion and try the Honeywell HIH-4000 Humidity sensor. The location where my project is intended to go experiences a wide range in temperature, from -40C to +40C. The Honeywell unit is rated to function when the mercury dips that low.

I looked at some other options, one of which was very appealing. The Precon HS-2000DD, which is incorporated into a socketable module, which would make replacement a cinch. Alas, it's not rated to below -30C.

Meanwhile, it's back to getting an LED to blink!

Jay

Florin, I just wanted to say your code worked right away! Great module. I coupled this with my module for the MS5540C for an upcoming wireless weather device!

http://www.sfcompiler.co.uk/wiki/pmwiki ... er.MS5540C

Thanks !

The post are very educational in terms of temperature sensors. Future readers can make this as a reference to solve their sensor problems. However, the sample codes that are in the ink in the first post is a bit hard to understand for newbies. I hope somebody can post a link that is more comprehensive.

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Refrigerator Water Filters

When I first saw this sensor, I thought it was the answer to a lot of prayers, however like others, I have found it is less than so.

As already mentioned,it's accuracy/consistency seems to be suspect. Also I found that the readings changed depending on the value of the pullup resistors (strange for digital lines).

I also found that it is quite easy to destroy them.

I am now looking at the HS1101, any opinions on that?

I am interfacing to PIC18F...... with USB output. I did get the code working without to much problem thanks to Mikroelektronika.