Spot Welder Control Board, Spot Welder Time Control Module Digital Display Controller Board (100A)

I think it would be nice if this device came with stand offs so you can attach the two boards straight away. you must use an AC power source for the logic board ... which is easy ... break open any 12 volt dc wall wart at the seam and remove all the electronics and come off the transformer directly. the unit pulses the welding transformer to moderate the intensity of your spot weld power this works better if you have a strong 20 amp breaker feeding your system. the pulsation of a transformer under full load makes a lot of noise in the electrical system so work as close to your main as you can like in the garage 10 feet away if you can.... all in all a great unit...

The vendor could not help me. I have the 100A TRIAC version. This controller is designed for 50 Hz line frequency but is being sold in the U.S. where the line frequency is 60Hz. The price was okay, but the advertising is deceptive and nowhere did it say that it was designed for 50 Hz power.You can tell this was designed for a 50Hz line by watching the TRIAC's gate and MT2 terminals with an oscilloscope. The first pulse is aligned with the 60Hz line, but the second pulse starts 10 ms later (50 Hz half cycle), not 8.33 ms later (60 Hz half cycle). This continues, turning on the TRIAC in seemingly random locations in the middle of successive cycles. Its just plain wrong (because it's designed for 50Hz). However, the high power 100A section of the board, which is connected to the microprocessor controller with an opto-coupler, works great, so I modified and added circuitry to the controller to make it work in my battery tab spot welder.

fast

The timer is settable for number of line cycles duration and fraction of each cycle's ON time. It DOES provide control of output power, but with a few deficiencies, at least in the unit that I received. My initial impression was that the most power it delivered was much less than my transformer system can produce when not using this timer. I investigated, using a 20-Ohm heater as a pure resistive load, 230 VAC, 60 Hz, producing 11.5 Amp load, and an oscilloscope, to observe the output waveform. I found that the first output cycle was often triggered at the AC zero crossing, which is generally not a good idea for control of transformers, because of very high inrush current. In my system, inrush current is well within the limitations of the 100 Amp triac, but this is still not the right approach for control of transformers, especially high-power transformers. Also, triac conduction was only occurring during single half-cycles, which is also not a good idea. I repeated these tests with 1 Amp load, and I saw similar results. I will be using a different control approach.

The package was open when i got it and I now see that you need a AC transformer to produce 9-12 AC volts.

I have almost new RT battery to power this control board. I put it on max power, but still won't work

Multiple components on the board arrived broken

Worked fine.