Simplest Variable Fuse

Justin Roeder — Tue, 10 Sep 2024 14:52:13 +0000

This is a TL431 comparator fuse that can be made on a breadboard,pcb or even copper tape. It uses a 1.5V Battery(Can be AA,AAA,C or D). Its used to add 1.5V to the voltage drop across the current sense resistor. This is needed since it can only turn on at 2.5V at the reference pin. The 431 can be found in a lot of switching power supplies, just look for a tiny transistor looking device containing the number 431. This fuse is better than poly fuses and circuit breakers.

Here are some equations for current sense resistor:

$$R_{sense}=\frac{1}{I_{trip}}$$

$$P_{sense}=I_{trip}^2R_{sense}$$

$$V_{max}=\sqrt{R_{sense}P_{sense}}$$

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Solder Iron Foot Switch

Justin Roeder — Sun, 29 Nov 2020 00:02:14 +0000

This switch is a must for people who solder alot. It prevents the iron from overheating. Its very simple and is very cheap. Some irons like mine can heat back up fast after they have not been cooled down alot.

You will need the following parts and tools:

Cable with outlet and switch
Hot wire and switch with tab broke off
Socket and 3-prong cord Top outlet is connected to the switch and the other is wired directly
Neutral wire connected to the terminal with the tab unbroken. And ground connected to the screw
Break off the tab in Yellow

To break off the tab use your pliers and bend the tap back and forth until breaks off and leaves the two screws on the hot side not connected together

The post Solder Iron Foot Switch first appeared on Delphijustin industries.

safety switch - Delphijustin industries

Simplest Variable Fuse

Solder Iron Foot Switch