What you get:
- A set of 2 diodes.
- Schottky: VS-100BGQ015 Mouser.com Part: 844-100BGQ015
- TVS: 5KP13A-E3/54 Mouser.com Part: 625-5KP13A-E3
I do not make big profit on these diodes. It is more like a service, so you can upgrade your Spot Welder relatively cheap if you want. The cable for the diodes should be 10mm² ( 7 or 8 awg). For the tvs diode you can also use thinner cable if it is just a very short piece.
What is it for?
These diodes can be used to make the spot welder more reliable when using very high welding currents or long welding cables. They reduce the peak voltage which appears because of the inductance of the welding wires. This is necessary because high voltage spikes could damage or kill your mosfets. A very detailed explanation whats going on can be found here https://endless-sphere.com/forums/viewtopic.php?f=14&t=81400&start=550#p1218325
I also did some basic oscilloscope measurements myself. You can see them with a short conclusion on Instructables
How to connect to the Spot Welder: