Thermal energy; where it comes from, and how to keep it from damaging components

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85 views

Why and when do SSRs heat?

I'm using a 40A 120VAC SSR to control a 10A resistive load. It gets hot during use. Is this heat associated with the switching, with the load current, or with the voltage? And where does it come ...
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0answers
31 views

Could I use two 120V ac Heating-Mats directly with 230V mains current?

i want to improve my simple oven. Until now I used several light bulbs (100W, 230v) in ceramic sockets to achieve arroud 95°Celcius, then the circuit is cut until the sensor is measuring 90°Celcius ...
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2answers
93 views

Smartest way to use current limit using LM317?

As i understand, using this circuit: Will cause the current to go right through the POT and resistor, which will generate a lot of heat. Is there a better way to use current limiting with LM317 ...
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2answers
79 views

heating a 5 ohm resistance with a 9V Battery

Hi I am working on a project which involves heating a resistor with a 9v battery. I am heating resistance because I want to increase the temperature of a temperature sensor so that I can do something ...
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0answers
35 views

How to make copper wire igniter

How can i make a copper wire 200 mm long, heat to 500 celsius with 300w and not burn out? The 200mm wire will be something like 0.1 ohm and volt / ampere at 300w there must be 0.8 ohm´s. resistors? ...
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0answers
33 views

FabRoc heating system vs. carbon fiber tape [closed]

www.exo2theheatinside.com VS. Carbon fiber Tape I am making a battery operated heated blanket for my science fair project. Can you kindly tell me how the FabRoc heating system differs from the ...
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0answers
23 views

calculating circuit for NiCr at a set temp

This may be a primer for most, but this is the first time working with resistance wire and I'm unfamiliar with it's qualities I want to create a circuit that will heat a length of wire to a set temp. ...
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1answer
34 views

Need help making a forced air heater

I would like to make an electric heater. It will have a 20" Lasko Box fan at the back, pushing air passed the Kanthal A1 resistance wire. I would like to use 120vac. It will dissipate 1000 watts, and ...
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1answer
71 views

Chinese glue gun small resistance [closed]

So I've bought Chinese glue gun at ebay, but it had incompatible power plug and terrible cable. I decided to replace wire and plug. I disassembled gun, and saw that wire goes straight to tip (which ...
2
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1answer
44 views

Power dissipation when connecting LED to +-15v

In my audio project that is powered off dual +/-15v rails, I would like to connect a simple LED indicating power on. However, when I connect it with a 1.5k resistor in series (2W), the ~28V dissipated ...
6
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3answers
1k views

Coffee warmer capsule

I want to make a small capsule that you can throw in your coffee and keep it warm (not hot, lets say about 40-50C). In the first place, I don't care about power supply - I will have 2 wire going into ...
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2answers
52 views

Calculating Power and Setup using resistors as heating elements

I looked around at other questions, and either I didn't understand what all I was reading, or it didn't answer my question so if there is an article that I've missed feel free to redirect me. I'm ...
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2answers
57 views

What is the intended use of high current SSRs and triacs?

I answered a question recently regarding power dissipation in solid state relays. This is the calculation: Consider this 40 A rated triac - BTA40. Vto = Threshold voltage = 0.85V = Voltage drop ...
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6answers
2k views

Is a microwave's output power proportional to the mass of its contents?

My friend and I are having a heated debate. On the one hand, he thinks that a microwave oven that is empty, consumes almost no power (not considering lights, lcd, etc). He says that once you put an ...
3
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2answers
197 views

nichrome wire not heating up

So today I was working on a DIY project, that involves me heating up a nichrome wire, and for some reason the nichrome wire is not heating up. I am using a 38 gauge wire, I calculated that I would ...
0
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2answers
214 views

What wattage heating element required for 500 degree Celsius oven temperature

i have 32 litres OTG oven which is of 2000 watts and can generate Max. 250 degree Celsius . 40 Litre capacity 2000 watts OTG has 2 heating elements, one at top ...
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1answer
51 views

Why do my led bulbs state: not for use in totally enclosed luminaries?

I recently bought some nice inexepensive LED bulbs but I noticed the warning states: (see image below) not for use in totally enclosed luminaries I am guessing that it gets too hot but I find it ...
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0answers
47 views

Fixing a heated water dish: Pointers to a temperature table or guide for power resitors?

I'm fixing a heated water dish, used so that the dogs don't have to eat snow. The previous dish was heated with a wire embedded in what appears to be ceramic, on a foil back on the bottom side of the ...
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0answers
33 views

Constant Current Source - Variable Power

I am planning to carry out an experiment whereby I have to heat a graphite heater .Dimensions are length- 15 cm, Dia - 1 cm. My requirement is to vary the watt-density on the ...
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1answer
41 views

IC out of oven after baking

Is it ok to take out the ICs/components from oven immediately after baking hours? Or is there a standard cool down temperature before opening of the oven after baking?
2
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1answer
26 views

High Temperature Conductor in Air

I am trying to determine what the best material is for a high temperature conductor. It is for distributing power inside a furnace. I need to run at around 1000 celsius (the furnace is hotter but this ...
0
votes
1answer
79 views

How do modern electric blankets implement thermal sensing/feedback?

I'm looking to build my own 12VDC controller for a low voltage electric blanket (specifically, this blanket http://www.amazon.com/gp/product/B0041RQXKE ). An obvious implementation with a ...
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1answer
49 views

Heating Surface

I'm working on a school project, which entails heating a polycarbonate surface to melt a small amount of snow accumulation on top of it. The polycarbonate surface is 2 ft x 2ft. Our original concept ...
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2answers
44 views

PCB coating for a high temperature environment

What PCB coating is good for a high temperature environment (my environment is about 30-70 C), and is available in a spray can or so that is easy to implement without need of a device/machine?
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1answer
62 views

Verification on Ohm's Law?

I'm building some Heated Motorcycle Grips and I think my calculations are off. Can anyone help me verify that for 10 feet of 20 gauge Nichrome 60 wire, I have the correct Ohms, Watts, and Amps for the ...
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1answer
57 views

PWM a heatgun using a relay

I need to control a heatgun temperature. My heatgun have two different temperatures, one about 300° and another about 400°/500°(something like that) with 2kW max power at 220v. I've connected a ...
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2answers
194 views

PCB Heater design issues

I'm using copper tracks laid out on an FR4 board as a heater device. It's a serpentine design with the copper 0.3mm wide and 0.2mm spacing. I have three sets of tracks which I intend to heat up at ...
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1answer
49 views

Thermo energy. How does it work and how can i do it!? :D

I see youtube videos where people use heat from their hands and other places on metal to create energy. But most of the time there's a cold side. How does all this work and how could i make a simple ...
2
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2answers
53 views

How does IR thermal vision work?

How are IR thermal-vision devices able to present us with "invisible" imagery in such a way that we can actually interpret it? What I'm really trying to wrap my head around is: How a sensor can ...
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2answers
96 views

Overheating heating element

I'm making a system that is going to heat water in a 25 liter tank to a given temperature and keep the water on this temperature with a precision of +/-0.5 °C. As I have done some research I have ...
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3answers
127 views

Why are diodes heating up and smoking?

I'm following this guide for battery powering some Adafruit NeoPixels. It states that I should put a 1N4001 diode in my circuit to lower the voltage to avoid having too high a voltage and destroying ...
0
votes
1answer
93 views

What is the efficiency of electric power converted to heat?

I'm trying to understand how much heat is generated when a given amount of electric power is drawn. And from what I understand, it's pretty much 1 to 1 isn't it? Example: If I have a 1 HP motor ...
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0answers
68 views

What components work better when they warm up? (apart from vacuum tubes)

Conventional wisdom is that heat is bad for electronics. Metals and most doped semiconductors conduct more poorly, and everything ages faster. But in my experience, some faulty appliances don't work ...
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4answers
90 views

Light effiency or efficacy and watt to heat output

I am on a light forum and there are debates about watt heat output of lights. I'm using my common sense for the debate but can't find the data online to support my ideas. People are thinking that ...
0
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1answer
78 views

Help Me to Identify what is the Cause for Heating with this Circuit

I built below voltage Regulator Circuit and noticed that after sometime 1K resistor is getting a lot of heat and also I connected the multi meter to Output of this circuit and adjusted preset to ...
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1answer
62 views

Molybdenum Heater Wire

I have a 12 foot length of 14-gauge molybdenum wire that I have measured a resistance of 1.2 ohms. I would like to use it as a small heater coil. How can I calculate the safe number of volts that I ...
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1answer
77 views

How to remove heat from a body and cool it below room temperature?

In college I was told that we can heat a metal sheet if we pass enough current through it (Eddy currents). But is it possible to somehow cool an object (metal sheet) using some circuit? The ...
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3answers
115 views

Determining Resistor for Heating Element

I am attempting to run a Molybdenum heat coil. The best I can tell it is 0.3-0.4 ohms per rack and I would like to run say two racks at 230V at 3.9KW (so it doesn't trip my 230V 20 amp breaker). Does ...
0
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1answer
48 views

Heatsink surface temperature

This question is related to who knows how to design a thermal management. I started learn to do this, at hobbyst level. So, this is the assumption of the situation: When someone design the thermal ...
0
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2answers
61 views

LD1117 Heat Sink

I'm about to put a LD1117 Low drop-out regulator in SOT-223 package into one of my projects and wonder if the heat sink is internally connected to anything. Unfortunately the data-sheet doesn't ...
0
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1answer
380 views

Why is it dangerous use a coiled extension cord

What aspect using a coiled extension cord makes it more dangerous than using an unrolled power cord. Many fire safety websites reference that an extension cord should not be used while coiled. Is ...
2
votes
2answers
100 views

How can I make nichrome wire perform more consistent heating in liquids?

Was told to ask this here from chat. I have 32AWG nichrome water that I want to use to heat liquids. I submerged it into water and noticed that the part outside of water is glowing red, but the part ...
2
votes
2answers
215 views

Why do the high side MOSFETs get hot in this buck converter?

Here I am attaching step down buck converter circuit. While testing, mosfets on high side get hot extremely high even for 100W load. Low side has no problem. All mosfets are fixed on very big heat ...
0
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2answers
77 views

How can I quickly heat something to a given temperature with nichrome wire, while keeping the wire itself under a given maximum temperature?

I'm trying to heat a fluid to a certain temperature (under 100C) using nichrome wire, with a thermistor measuring the temperature of the fluid to allow controlling the nichrome wire using PWM and a ...
0
votes
2answers
126 views

How to create a small heater from batteries

How should I go about creating a heater from batteries (AA/AAA/9V/C/D any will do) that last as long as possible (the longer lasting the better)? I have seen this post. But that only lasts 45 mins ...
0
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1answer
52 views

Heating wire filament with low voltage high current?

Is it possible to heat nichrome wire with 0.5V 20A? what is the different between heat produced by 0.5v 20A (10watt) and 10v 1a (10watt) ?
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1answer
168 views

Transistor overheating in seconds when connected to usb power source

I am following this tutorial and have managed to make a working circuit but when I connect it to a high current power source such as a USB 3 port, the transistor gets so hot that I fear it may burn ...
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3answers
208 views

LED without resistor

I know Ohms Law, i know leds need resitors. My scenario is this: I need to make a little circuit that controls 2 RGB leds with a 9 Volt battery. This gives an avergare o 5 hours of light before the ...
2
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0answers
45 views

How to model the energy (heat) dissipating from a power resistor? [duplicate]

The issue I'm currently struggling with is: What is the mathematical relationship between power dissipation and temperature in a resistor? The project I'm working on is a controller card for a ...
2
votes
2answers
79 views

Tomato Seed Warmer

I wonder if there is a very simple way to control one or two light bulbs in a box that are providing heat for my Tomato seed Propagator sitting on top ... i.e. I need the heat underneath...It would be ...