How Many Amps Does a Soldering Iron Use?

This site contains affiliate links to products. We may receive a commission for purchases made through these links.

Soldering takes power

Most people look at the number of volts and watts in making their decision and often overlook how many amperes the soldering iron will use. The importance of amps is that this is a measurement of how many electrons pass a given point in one second.

To learn more about amps and how many a soldering iron uses just continue to read our article. It is filled with the information on how many amps a soldering iron uses. Keep in mind that the different styles of soldering irons will use different amounts of amps.

AdobeStock 198871668 1

It’s all in the equation

Whenever you are trying to figure something scientific or electronic out, there is always an equation to help you get your answer. The equation to figure out amps goes like this: amps = watts divided by voltage.

Then to figure out total watts or voltage you just move the components of the equation around- volts times amps gives you watts and watts divided by amps equals volts.

For example, if you have a 25 watt, 12 volt soldering iron, that tool would use 2.1 amps.

How many amps does a soldering iron use?

As has already been said different soldering irons use different amounts of amps. Usually the total of amps is listed in the specs when you buy the iron at the store. However since some people say that since watts depends on amps, amps is not giving you any new information.

If you do not understand all the talk about watts, volts and amps, here is an old analogy to help you grasp what is meant. Take a standard garden hose and hook it up to the faucet and turn it on.

Voltage equals the pressure of the water when the water is turned on. Resistance is the size of the hose so a 3/4 inch hose has less resistance than a 1/2 inch one. The size of the hose determines the flow rate of the water or the amps.

Watts equals the pressure of the water coming out of the hose at the other end. Each soldering iron is not built the same and you can build your own 16 or 24 volt soldering iron and end up using only about 2 amps.

One 30 volt soldering station uses about 5 amps. A 20 volt soldering iron will use about 2 amps. The amount of amps you will use at any given time will depend on the model of the soldering iron and how it was built.

Our comparison chart

To see how a soldering iron stacks up against other appliances, here is a little comparison chart to give you a good idea where a soldering iron lies in the scheme of things.

NumberApplianceAmpsNumberApplianceAmps
1.Blender307.Microwave110
2.Clock0.088.Belt sander50
3.Coffee maker809.Bench grinder37
4.Computer1010.Soldering iron2
5.Dishwasher12011.Electric shaver1.5
6.Freezer5012.Toaster100

Soldering electronic guitars and amps

When you have specialty equipment that needs good connections to produce that top sound you want, you do not need a very powerful soldering iron. The other side of the coin is that you do not want one that is not strong enough to handle the task at hand.

The ideal power of a soldering iron to make the right connections in electric guitars and amplifiers is roughly 70 watts. You probably could get away with using a 50 watt or even a 60 watt iron but you want it strong enough to melt the solder.

Electronic solder has a melting point of roughly between 361 and 374 degrees F. You should avoid using a soldering gun on these precision instruments as those get too hot and may ruin your pick ups.

Solder melting points

Like soldering irons and their different amp use, solder has different melting points. Knowing the melting point of the solder will help you find the right soldering iron with the right amount of amperes to handle your workload.

Solder alloyMelting point- F
5Sn-95Pb585
100Sn3450
Sn/3.0Ag/0.5Cu426
50In-50Pb402
55Sn-45Pb379
62Sn-36Pb-2Ag354
97In-3Ag289
52In-48Sn244
45Sn-55Pb400
60Sn-40Pb368

This gives you an idea on how hot of a temperature you will need when doing your next soldering project

Soldering iron safety

This cannot be stressed enough as soldering deals with toxic fumes, high temperatures and tight spots at times. You should practice good safety habits all the time when working with solder and soldering irons

  1. Fumes— a lot of different types of solder contain lead. When heated that lead can emit dangerous fumes that may put your health at risk if you are not in a well ventilated area,. Work in a well ventilated area or use a fan to help get rid of those fumes
  2. Flying solder- this does happen when you are desoldering different connections. Wearing proper eye protection will keep those tiny pieces from landing in your eyes. If you are pulling on a wire watch out for those ends a well.
  3. Fire– solder and solder irons work at very high temperatures. That means one wrong move and you may start a fire or damage nearby objects. Keep your work area clear of any objects and use a heat resistant work pad. No matter how careful you are accidents do happen

Some final words

To be honest, amp use is not the most important piece of information on a soldering iron. While it does have some importance you can get the same information from looking at the watts and volts specs.

Most people look at those two factors over amps almost all the time. When using a soldering iron make sure it is not too powerful for your task. You may like a lot of power but that extra boost can harm components if you expose them to too much heat.

Find the right soldering iron with the right amount of power for your soldering jobs.

About The Author