ELECTRONICS - [solder station protection] - [page 1/5]

Soldering Station: Introduction

Velleman kit K2579

As I already told before the project is based on the Velleman kit K2579. This kit is a timer module with two buttons: start and stop.

The timer can be started by pressing the START button. This will close the relay for a predefined amount of time. You can set this time by regulating a trimmer on the PCB. By default the time can be set to anything between 0 and 15 minutes. To stop the timer before the time elapsed you simply have to push the STOP button.

Circuit

The circuit below shows you the basic circuit of the K2579 kit. I am not going to discuss the circuit in details as it was not created by me but basically it uses the 555 timer IC. The surrounding resistors/capacitors are dimensioned in a way to allow a time delay between 0 - 15 minutes. The delay itself can be chosen with trimmer R6.

The output of the timer IC is connected to a transistor (BC547) to switch higer currents. This transistor will switch the relay on or off.

This circuit would suit fine to build a soldering station protection, but I wanted to add some extras: I tweaked the circuit a little bit.

schematic diagram for the K2579