Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [humidity]

109 questions
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Why are SMD LEDs shipped in a sealed bag containing desiccant?

I had a selection of 0805 LEDs in my last Mouser order and was a bit surprised to discover they arrived in heat-sealed (rather than folded and taped with sticker) bags containing a desiccant bag and some sort of litmus-esque paper indicator saying…
scanny
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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 inside (see attached). The product was installed…
Transformer
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What's the best way to protect a board from corrosion in a hot/moist environment?

Some of my projects need to live outside for long periods. Sometimes, moisture gets into the enclosures. That means that a circuit board might be sitting around in contact with water for hours on end at upwards of 100F. I've noticed that solder…
edebill
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Soil moisture measurement

Background To kick-start my longstanding ambition of getting back into electronics, I decided to try and make a device that measures the soil moisture of potted plants to determine whether they need to be watered. The aim for the first incarnation…
drxzcl
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Best humidity/temperature sensor for a nappy?

Special needs kids have big troubles with potty training. A 'wee-wee' alarm would be of a lot of help. What would be a good way of detecting 'it' without electrocuting anybody? A possibility would be to detect humidity or temperature but it really…
roberto
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ICs with humidity or moisture sensitivity - bake recommendations

I purchased some ICs recently that included something I'd not seen before - a moisture 'sensor' on a paper strip with color indicators for a few specific levels of humidity. Once the paper reaches a given moisture level, the color on the paper…
ejoso
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8
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Use of desiccant for storage and delivery of electronics

I have several questions regarding desiccant and electronic components: Is there a rule of thumb on how much desiccant, let's say silica gel, to use per volume unit or per package area unit? Must a package be very well isolated for the desiccant…
NoobPointerException
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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 strange behavior (oscillating/irregular voltage…
Sredni Vashtar
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What are viable approaches to a circuit to detect wet/moist cloth (bed-wetting)?

Trying to design a circuit that can reliably detect a situation where a child wets their bed. The 3 key requirements are -- Reliability of the approach Ease of use, i.e. a no-fuss approach Child's safety (from harm) due to electronics Can the soil…
bdutta74
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High Temperature Humidity Sensor

Where can I get a high temperature humidity sensor for temperatures up to 700 or 800 degree Fahrenheit (~ 370 or 425 °C)?
mad_z
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How "pinless" moisture meters work?

I see that there are "pinless" moisture meters on the market, e.g., http://www.omega.com/pptst/HHMM257.html that look like this My understanding is that they measure the amount of reflected RF. Perhaps, it's because liquid absorbs RF. However,…
John M.
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Is there a sensor that is equivalent to a dry toothpick?

For the non-cooks in the audience the dry toothpick test is used in baking (cakes, banana bread, etc.) to determine when the item is done baking. The procedure is to stick a toothpick into the food, pull it out and look at it, If it came out moist,…
hildred
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1-wire humidity sensor with ID

I've created a temperature monitoring system using multiple DS18B20 temperature sensors and now I want to add some humidity sensors to it. The problem is that I cant find any 1-wire humidity or temperature/humidity sensors that use ID logic similar…
Denis Gburg
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PID implementation for a Humidity controller

I'm working on a humidity controller which uses PID algorithm to control the process values. I have to implement 2 PID routines as there are 2 process values ( Humidity and Temperature) to be controlled. I read many articles on PID controllers and I…
raforanz
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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 covered with commercial component selection…
Stefan Wyss
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