anyone with this Arduino setup also use the TVS and Schottky diodes? I just finished reading through the 24 pages on ES (from Riba’s original JP welder) and this seems to be recommended by the gurus.
I’m going to mangle it, but basically there is an avalanche current for ~100 microseconds which is known to fry FETs. They added two components - the Schottky and then TVS to minimize this and extend the life of the spot welder. They are two small components and only $3-5ea. I think i understand how to wire these in, so will give it a shot when i build mine. I got a board (and a spare) so just waiting on components from Mouser.
I also went with the 1324 FETs as they were recommended as an upgrade. A bit more $, but marginal additional cost.
That is speaker wire with 2.5 mm^2 on each strand.
I combine four of them together to get 10 mm^2.
Why I used speaker wire? Good question!
I had it and it is quite flexible. It should do the job well and handling of the electrodes will be easy.
@sl33py No I haven’t updated anything. I see that thread on ES the first time right know
Looking forward for your build.
Damn mine isn’t working. I think I destroyed one to some of the fets due to heat.
If I measure the resistance on the legs there shouldn’t be a connection right?
Mine circuit shortened and the switch does nothing and the current flows the whole time.
The potentiometer works but the display does not show anything.
Do I have to program this tiny computer before? @Maxid
@sl33py do you have a list with all necessary parts for the upgrade? Since I have to order new fets I could add them as well.
Tried mine today with nickel strips - it works in principal but even at 20ms it does not weld two strips together. They stick slightly but can be pulled apart easily. Any idea what I can do? Battery is a car battery with max discharge 700A
Ok may be something in the settings as similar setup to mine just I’m using a high amp push button switch. What do you copper probes look like nice point on them.
1 - That change was added by the author to let the PCB manufacturer accept it as a single PCB. You can cut it as printed on the board.
2 - From the instructables page:
In the new Version you have to connect JP1 on the Arduino Board with JP1 on the Mosfet Board and JP2 on the Arduino Board with JP2 on the Mosfet Board. Use pin headers and sockets. These jumpers connect the ground of the two boards.
Unfortunately those are called JP1 and JP2 on the Mosfet Board and JP3 and JP4 on the Arduino Board…
Looking forward for your build.
I’m sorry but I’m really clueless…
