Programming sensors

Thread Starter

man111111

Joined Mar 15, 2020
9
Hello,

This is my first ever post :)

I'm currently looking into programming a humidity sensor. I have been given the impedance vs RH% graph on the data sheet. However, I would like some advice on how I should go about programming the humidity sensor.
 

djsfantasi

Joined Apr 11, 2010
6,412
Wait a minute... what are you programming? What sensor are you using? Is it even programmable?

I have dozens of questions. Let’s start with those three?
 

Thread Starter

man111111

Joined Mar 15, 2020
9
Wait a minute... what are you programming? What sensor are you using? Is it even programmable?

I have dozens of questions. Let’s start with those three?
Hello,
hcz j38 Is the name of it but have no idea how to use it so that I can record the humidity.
 

djsfantasi

Joined Apr 11, 2010
6,412
Hello,
hcz j38 Is the name of it but have no idea how to use it so that I can record the humidity.
I searched for “hcz j38” and couldn’t find anything. So let me tell you a hint. When you have the right part number, type it into the search bar and add “ Arduino” after it. You’ll usually get sample code, typical circuits and maybe even a library you can download.
 

atferrari

Joined Jan 6, 2004
3,954
Show a picture of the sensor so we can read the ID.

Humidity sensor Multicomp HCZ J3B, most probably.

I suggest you to start furiously to search the datasheet. Do not be lazy.
 

Thread Starter

man111111

Joined Mar 15, 2020
9
Show a picture of the sensor so we can read the ID.

Humidity sensor Multicomp HCZ J3B, most probably.

I suggest you to start furiously to search the datasheet. Do not be lazy.
Hi, I looked at the datasheet but it doesn't mention how I can use it with a LCD. I'm not sure how I should use the impedance vs %RH graph to help me...
 

OBW0549

Joined Mar 2, 2015
3,388
Hi, I looked at the datasheet but it doesn't mention how I can use it with a LCD.
Of course it doesn't. Why in the world would it? It's just a sensor, not a complete sensing/processing/displaying system. If you want to display humidity on an LCD, you're going to have to figure out how to do that on your own. It will involve not only the sensor, but signal conditioning circuitry, a processor (e.g., an Arduino), and the LCD as well-- plus a lot of programming of the processor to convert raw measurements into displayable results.

I'm not sure how I should use the impedance vs %RH graph to help me...
If it doesn't, you're going to have to do a LOT of learning before you can use this sensor.

This sensor operates with AC excitation (1.0 volt MAX, 0.5 ro 2.0 kHz) and will require some very specialized circuitry to convert its impedance to a DC voltage that can be read by an Arduino or other processor having an analog to digital converter. Designing such a circuit is not-- repeat NOT-- a task for a beginner and is not a very easy task even for an experienced designer.

Based on your questions, and having looked at the sensor data sheet, I have to say that it looks to me like you're in way, WAY over your head with this thing. It would be best, for the sake of avoiding enormous confusion and disappointment, to start with a simpler project.

Sorry, but that's the way I see it.

(The data sheet I looked at was here.)
 

ci139

Joined Jul 11, 2016
1,444
That link consistently brings me to a malware site.
if you call Google Search - Wikipedia such . . . i have noticed the trend lately , that at the end of results list there is a higher concentration of "irrelevant" or commercial links (applies to more general search terms) -- some of which may pose potential hazards if you don't close them and click where it happens . . . sorry to say but i assume the members here have a brain and know how to get around in www
 
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SamR

Joined Mar 19, 2019
2,100
Two things, how to connect to the LCD, then how to write to the LCD. Good LCDs should have a 2 wire connection otherwise it will take a LOT of pins. Depending on the type of LCD (graphic or digital) you may also have to learn the code for the graphics.
 

atferrari

Joined Jan 6, 2004
3,954
I have no idea what you know about all this but I was about to comment in line with what OBW0549 told you.

Once you have learnt how to measure the output from the sensor, you need to process it and then display the numerical value somewhere.

My first complete design was something very similar: a temperature data collector for a green house managed by a small microprocessor.

I climbed up the whole ladder learning about the sensors up to the display and, of course, programming the micro as well.

My suggestion: resist the temptation to come every minute to ask questions in a forum. Do your effort while you practice with the real hardware. Come to a forum for specific doubts that you honestly cannot solve. Buena suerte.

I am done.
 

MrChips

Joined Oct 2, 2009
21,059
Chill out fellas. This is a new member who is just getting his/her feet wet.

The datasheet for HCZ-J3 is available here.

HCZ-J3A Humidity Sensor.jpg

Now you need a system that will measure impedance and temperature.
How much experience do you have to tackle this?
 

Thread Starter

man111111

Joined Mar 15, 2020
9
Chill out fellas. This is a new member who is just getting his/her feet wet.

The datasheet for HCZ-J3 is available here.

View attachment 201644

Now you need a system that will measure impedance and temperature.
How much experience do you have to tackle this?
I've only been studying electronics for about 8 months by reading books and watching YouTube videos and decided that I wanted to make my next project using a humidity sensor.

I've programmed a few stuff using microcontrollers and I've made some stuff using opamps, resistors, transistors and LDRs... but havnt worked with capacitors but have studied them.

I've also studied the transistors inside opamps

:)
 

jpanhalt

Joined Jan 18, 2008
9,363
If a program is not given on the Arduino site, do you have experience writing microcontroller (MCU) code? What language? Do you know how to use a look-up table or do an approximation of that line? You will also need to measure temperature.

You might be able to find a probe that has been linearized. You will still need to measure temperature, unless it includes that too.

This is an example of an integrated temperature and humidity sensor: https://www.maximintegrated.com/en/products/ibutton-one-wire/data-loggers/DS1923.html

I did not look at the datasheet -- I have to fix dinner first.
 

Thread Starter

man111111

Joined Mar 15, 2020
9
If a program is not given on the Arduino site, do you have experience writing microcontroller (MCU) code? What language? Do you know how to use a look-up table or do an approximation of that line? You will also need to measure temperature.

You might be able to find a probe that has been linearized. You will still need to measure temperature, unless it includes that too.

This is an example of an integrated temperature and humidity sensor: https://www.maximintegrated.com/en/products/ibutton-one-wire/data-loggers/DS1923.html

I did not look at the datasheet -- I have to fix dinner first.
I've studied C,C++ and assembly code. How can I make an approximation line from the graph or use the lookup table provided in the datasheet?
 
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