I have purches a humidity sensor HS230. it has 4 pins. but i cant understand how to connect it properly.?

i cant understan where i connect Vcc and ground and from which pin i get output. please help me.

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Seriously, take it back to the store you got it from, its THEIR problem to find out how to use it, if they sold it to you .
AndyGadget6 years ago
A bit of googling found the manufacturer's datasheet for the module, but strangely, it doesn't give the pinouts for the module.  There's also THIS photo, and most telling of all, THIS info.

From the last link :-
Pin 1 (RHS) = Vcc - connect it to 5V.
Pin 2 is the output which varies from 700mV to 3.3V as the humidity goes from 10% to 95%.
Pin 3 is 0V.
Pin 4 (LHS) probably goes to RT1 which would be a thermistor for temperature compensation - not used here.

The formula to get humidity from the output voltage is  H = (60/2.05)Vout - 6.9268

Have you tried these connections?
(The formula is from their specific device but yours will be similar. If you use (30 VOut) - 7 you'll be pretty close.
  Search Google for SY-HS-230 to see if this is the Humidity module that you have. The datasheets that are on the web for that particular module are somewhat incomplete and do not have the pinouts, however they do contain some useful information. The module appears to come in two flavors; a HS-230a and HS-230b. The datasheet has calibration curves for each module and suggests that the output is a voltage that varies from ~.58V to ~3.18V (depending on module). If the output is voltage based and not frequency based, you will have an easier time.

   Typically these types of modules have Temperature, Ground, Humidity, and Vcc pins. If you look at the silk screen printing on the PCB you might see an indication of which pin is which.  It would look something like "T - H +".

   Another idea is to lookup the chip that is processing the sensor's raw output. You might be able to track down a datasheet for it. With that information you can look at the PCB for the Vcc, Ground, and output pins traces to the connector.

  I hope this helps.
What a useless device. Never buy anything without a working datasheet. All the ones I've found have no wiring diagram !


NachoMahma6 years ago
. Link to datasheet?