Questions tagged [humidity]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
2 votes
1 answer
43 views

Power jack connector and moisture problems

I have an inquiry about a design with a 3-pin jack connector, the PJ-065A. Datasheet of this connector I want to use this power jack connector for a design. I have selected this component because of ...
latiaesa's user avatar
6 votes
1 answer
112 views

Humidity specification - is there a typical reason for a non-zero minimum?

I'm curious about reasoning in specifying the lower limit for humidity. Looking at a common and thoroughly documented device we interact with, the Siemens S7-1500 PLC, it specifies RH = 5%-95% Is ...
Pete W's user avatar
  • 1,517
1 vote
1 answer
71 views

Capacitive soil moisture sensor value drift over time

I am developing a system that can monitor a set of parameters (temperature, air humidity and soil moisture level) to be transmitted once per hour to an online server. This system is based on a Lilygo ...
Sandro Sartoni's user avatar
3 votes
1 answer
340 views

Impact of rain fade on 60 GHz radio links

I'm a junior network admin at an ISP and need your help regarding point-to-point links with devices using the 60 GHz band. PROBLEM Most of them, except the ones that are at very close proximity (e.g., ...
Giorgos Amoiridis's user avatar
1 vote
1 answer
90 views

Why is the DHT22/AM2302 sensor output value divided by 10?

The divisor of 10 in the signal processing formula, where does it come from? source: https://labprojectsbd.com/2020/05/17/how-to-interface-dht22-am2302-rht03-sensor-with-pic16f877a/
Angga Amalul Ahli's user avatar
0 votes
0 answers
50 views

PCBA corrosion voltage dependence

Let’s say a PCBA is located in a humid environment where condensation can occur in a worst-case scenario. Parts of the PCBA are low voltage circuitry and parts are high voltage, let’s say we have 3.3V ...
NoobPointerException's user avatar
1 vote
1 answer
79 views

Humidity sensor HIH-5030 false readings on PCB

I've created a circuit (schematic below) to measure humidity with a HIH-5030 according to its datasheet and an ATtiny85 and tested it on a breadboard, the readings are very accurate. Soldered on a ...
Torsten Römer's user avatar
1 vote
1 answer
133 views

How to change temperature and humidity sensor of XH-M452 thermostat?

there is a thermostat for incubator for poultry. People generally using this model XH-M452. But this thermostat has a problem, in high humidity environment temperature and humidity sensor of XH m452 ...
mehmet's user avatar
  • 1,119
1 vote
1 answer
316 views

How to interpret the analog output of this humidity sensor?

I have been given a humidity sensor to work with and the only info I have is an AliExpress listing that says that it's based on the HR202L sensor. The datasheet of the HR202L shows that its resistance ...
k.h's user avatar
  • 103
0 votes
2 answers
611 views

Wood moisture meter with a multimeter

I bought some firewood, but I do not think it is dry enough. I read a few articles about 18% - 20% moisture level, and I wanted to measure it, out of curiosity. I was about to buy an electronic ...
Basj's user avatar
  • 1,906
0 votes
1 answer
87 views

Using 5V output from an Adafruit SHT40 humidity sensor with DAQ system

Using the setup guide for the SHT40, the only way I can get humidity and temperature from the SHT40 sensor is to hook it up to an Arduino and interpret the data coming from the SDL and SCA pins with ...
Liam Warren's user avatar
1 vote
1 answer
111 views

Pinless moisture meters

I have read that most pinless moisture meters are based on the principle of capacitance. I know that when the material loses water, the dielectric constant of the material decreases and the ...
Sara SG's user avatar
  • 11
0 votes
0 answers
70 views

Capacitive soil moisture sensor and differential switch

While using a capacitive moisture sensor I experience this weird behavior: when I insert the moisture sensor into the ground, the line differential switch breaks. Thus, I need to disconnect both the 5 ...
vazquezjm's user avatar
1 vote
1 answer
156 views

Resistive Moisture Sensors, What is the purpose of the 2N3904 Transistor in the Sparkfun Circuit?

the two circuits below do the same things as far as I can tell, they both measure soil moisture using resistive sensing. However the one from Sparkfun is using a 2N3904 transistor, since the voltage ...
baebsndeep's user avatar
0 votes
0 answers
42 views

Feasibility of humidity controlled minifan part 2

Previously, I asked about the type of input that I should employ in my project which is a humidity controlled minifan out of a humistor, and I considered using DC. Now I'm asking how construct the ...
Julius's user avatar
  • 3
1 vote
1 answer
248 views

Is low humidity bad for HIPOT testing electrical harnesses?

From what I understand for HIPOT testing high humidity could be a potential issue because if cable insulators absorb moisture that could affect their resistance. What about low humidity? Is there any ...
David Allen's user avatar
2 votes
2 answers
774 views

Heating elements on humidity sensors like SHT32 or HTU21D, what are they for?

Why are there heating elements on these small humidity sensors? HTU datasheet, SHT31 datasheet Are they used to calibrate the humidity readings or something like that? I tried using both humidity ...
Etwus's user avatar
  • 171
1 vote
2 answers
645 views

Using the heater in a temperature/humidity sensor

I'm having trouble understanding how to use the heater in a temperature/humidity sensor. The spec sheet for the HDC1080 says "The heater is an integrated resistive element that can be used to ...
VE3LNY's user avatar
  • 21
0 votes
0 answers
115 views

Grove capacitance soil moisture sensor

I have a Grove soil moisture sensor that works, but I have trouble understanding how the sensor actually works. I think the circuit starts with the 555 timer, that outputs a 487 kHz wave (R1 = 1.5K, ...
CCC's user avatar
  • 1
0 votes
0 answers
128 views

Why do I have data on all MCP3008 pins with nothing connected

I have an MCP3008 analogue to digital chip connected to my Raspberry Pi 3b ...
Ross Drew's user avatar
  • 101
1 vote
1 answer
633 views

Conformal Coating on Raspberry Pi

I'm planning to build a security camera with a Raspberry Pi 4B in it with the camera being an IR camera I found online. Being a security camera, I'm planning to put it outside my house. Where I live ...
Hao C.'s user avatar
  • 123
2 votes
2 answers
93 views

Methods of measuring constantly high air humidity

How can I measure still air in 90-100% RH range with constant 25°C temperature?
Tomasz Kowalczyk's user avatar
2 votes
3 answers
531 views

Why don't we see electronic devices in bathrooms failing under such high humidity?

I recently read that the relative humidity inside a fogged-up bathroom, such as during/after taking a shower, should be close to 100%. And we know that bathrooms these days are filled with all kinds ...
The Pointer's user avatar
  • 1,271
5 votes
2 answers
1k views

Humidity design requirements

I have to design a electronics device that is specified for environmental operating conditions of 0°C to 60°C with 5% to 95% relative humidity (non condensing). I think the temperature part should be ...
Stefan Wyss's user avatar
  • 7,430
1 vote
1 answer
88 views

Capacitive distance sensor - humidity influence?

We are using a capacitive sensor to measure displacement (from here: https://www.micro-epsilon.com/displacement-position-sensors/capacitive-sensor/?sLang=en). However, we seem to notice a significant ...
Toffomat's user avatar
  • 113
0 votes
5 answers
3k views

AHT10 temperature and humidity sensor does not work anymore

I have used the AHT10 before, I liked it, it worked well. After that I bought new a AHT10 but it is not working with my Arduino. I am using this library. I checked closly, and there is only one small ...
mehmet's user avatar
  • 1,119
2 votes
0 answers
60 views

Transmission distance with AM2320 temperature and humidity sensor

I'm about to work with a temperature/Humidity sensor, this sensor has to be wired more than 5m and less than 10 m to my PCB board, I was going to use the SHT3xx sensors, these sensors work with I2C ...
joshua andres blanco jerez's user avatar
0 votes
0 answers
500 views

How to improve humidity sensor (Si7021) accuracy?

I am trying to measure humidity in a textile factory more accurately. I found this sensor Si7021 (circuit was copied from SparkFun this is the link from SparkFun.) It is measuring very good. I am ...
mehmet's user avatar
  • 1,119
0 votes
2 answers
212 views

Soil Humidity sensor value rising over time

So I have this soil humidity sensor placed in a pot. It's about half way in soil, cause that's how deep the pot is. I'm trying to get a pump to trigger once the soil dries out below 20%, but ...
R0b0tn1k's user avatar
  • 103
7 votes
2 answers
424 views

Why does my Vbe multiplier voltage oscillate when wet?

I've built a few Vbe multipliers as cheap temp sensors. I know there are better ways to sense temperature but I am not interested in accurate measurements, and my question is exclusively about a ...
Sredni Vashtar's user avatar
2 votes
2 answers
866 views

How does moisture get into silicon chips?

Many chips have Moisture Sensirivity Level rating (MSL) I am trying to understand how exactly moisture can get into a silicon packaged chip. Every document I read just states it can, but doesn't say ...
Arthur Tarasov's user avatar
0 votes
0 answers
65 views

Bad sensor values with D1 Mini v.3 and soil moisture sensor

I created a simple project using a D1 Mini v.3 connected with a Black 1.2 version soil moisture sensor. Sensor is connected with 5V and the A0 pin on D1. When I run this simple example: ...
danyolgiax's user avatar
-1 votes
1 answer
638 views

Is it reasonable a remote control works after being heated?

The remote control of my TV set is failing and I probably have to buy a new one soon. I changed battery, including from other device that is working, and there was no improvement. But it is ...
Claudio Saspinski's user avatar
4 votes
2 answers
3k views

Capacitive moisture sensor not quite working

I have spent the past few days trying to reverse engineer a capacitive moisture sensor I ordered from eBay a while ago. The particular one I received looks like this: What fascinated me about this ...
Alexander Richter's user avatar
2 votes
1 answer
157 views

How much time to wait before sampling new data from soil moisture sensor?

I am working with some cheap soil moisture sensors, as the ones on the picture below. One of the problems of these kind of sensors is that they must not be powered on at all times. If you neglect to ...
Cheche Romo's user avatar
1 vote
1 answer
192 views

How does BME280 measure air humidity?

I know that BME280 measures pressure using the piezoresistive effect, I suppose it uses the thermoresistive effect to measure the temperature. How about humidity? Any advice would be appreciated, even ...
Lukas O.'s user avatar
1 vote
0 answers
182 views

Capacitance to digital converter for moisture measurement

I'm currently working on a irrigation system for which I would like to build a low cost soil moisture sensor. I would like to measure the moisture levels of a given environment based on a capacitance. ...
Matthias Waelti's user avatar
1 vote
1 answer
93 views

Extension cord's power socket grounding pin soaked in cleaning agent sud, what is a proper way of cleaning?

I didn't really know what tags to use. Anyways, this might sound stupid, however I was cleaning up something above the extension cord which was laying on the ground, and while I pressed the wipe suds ...
appwizcpl's user avatar
  • 911
2 votes
3 answers
263 views

Humidity and Moisture in Submerged Die-Cast Aluminum Enclosures

I have an electronic enclosure (5" x 5" x 4") made of die-cast aluminum alloy (A360). I plan to use it under water (~5 ft) continuously. I first pressure test it: I monitor the pressure inside, while ...
RYao's user avatar
  • 21
0 votes
2 answers
167 views

How to use gold finishing to reduce corrosion on a moisture sensor?

Background I have a raspberry pi with a moisture sensor that suffers from corrosion. My setup is similar to the one described in this raspberrypi.stackexchange question about corrosion of a moisture ...
MuadDev's user avatar
  • 103
0 votes
1 answer
63 views

Basic Solenoid Question

I have a super simple question about solenoids. If I wired this, a 120v solenoid valve, to a 3 prong male plug would this cheap chinese humidity controller be able to control it? My assumption is ...
Hairball's user avatar
2 votes
2 answers
47 views

Extend life of hygrometer? (Prevent breakdown over time)

Context: I'm working on a gardening project using a microcontroller to power grow lights and other related components after I've built on top of it. Case: I was interested in adding some hygrometers ...
Sani Evans's user avatar
1 vote
2 answers
1k views

Can water condensation appear on PCB in IP67 enclosure box?

Does IP67 box protect PCB from moisture? If not, is it OK to have an outdoor air humidity sensor soldered on PCB in IP67 housing? Also if it doesn't block moisture, is there any reason to use IP65/...
user3613833's user avatar
0 votes
1 answer
108 views

Measuring direction of current to determine moisture is present

I am building a moisture sensor with an AC current to prevent electrolysis. The AC will be generated with a simple schmitt trigger oscillator with the midpoint reference set at 2.5V. Water would ...
Hamoudy's user avatar
  • 159
1 vote
0 answers
262 views

Honeywell I2C RH Sensor SDA line experiencing fluctuation between Vdd and Vdd/2

I had a problem when implementing I2C communication between NXP Kinetis K50 micro-controller and Honeywell Humidlcon I2C RH sensor. The RH sensor doesn't acknowledge when receiving the default address ...
Shishiker's user avatar
0 votes
1 answer
91 views

Help with Arduino loops please! [closed]

So I have an Arduino Uno and I've made a device to humidify my the enclosure for my Tortoise. The device consists of a temperature and humidity sensor, an LCD screen to display temperature and ...
SatsumaSegment's user avatar
0 votes
1 answer
162 views

How to find the actual measurement range of a temperature sensor, HTS221?

I am considering to buy the HTS221 Digital Temperature and Humidity Sensor by STMicroelectronics. The datasheet says the operating temperature of the sensor is from -40°C to 120°C. But on page 33 of ...
Abhilash Iyer's user avatar
33 votes
9 answers
15k views

Moisture Trapped in IP66 Enclosure

I got a field report of a product which is sealed in an IP66 aluminum die cast body. it was observed that water/moisture had condensed inside the enclosure over and over and creating some white marks ...
Transformer's user avatar
0 votes
4 answers
697 views

Voltage Dividers for a beginner (with respect to soil moisture sensors)

I've just started with electronics and want to make an analogue soil moisture sensor (with Arduino). When I looked online for an explanation of the working, every site said that it works as a voltage ...
MLpranav's user avatar
0 votes
0 answers
80 views

Waterproof PCB pump driving stage

We are having issues with a small 12V DC pump which is used in a number of test systems in the field. The pump is powered by a standard DC power supply and integrates a small PCB driving stage, with ...
Francesco's user avatar
  • 1,025