You are welcome.

That's the square root of 2. You use it to pass from RMS to peak value.

Multiply the AC RMS value by 1.41 to get peak. When rectified and filtered the capacitor charges up to peak.

Fry the transformers.

If they are the same voltage and the phasing is correct. The current max would be based on the max current of the smallest transformer.

It's doable I can explain if you want

@@mattbanks3517 please do I’m having a pain in the ass to get magnesium carbonate bricks

@@dummieall3150 first of all are your welders transformer based? or inverter? Second what wattage are they and what kind of outlets have you got, can one outlet supply enough current for all the welders.

@@dummieall3150 my current welder i diy built from 2 big transformers wired in series. I wound each primary to work with 110v because i have a 220v outlet single phase.

Connecting in parallel at the AC side adds the amps. But the zero test between the two transformers must be done first.

If in parallel then yes. If in series max current is limited to the smallest transformer.

If connected in parallel the transformer MUST match very closely. This is not a resistor or capacitor. Measure between terminals when connected on one, should be zero. If not change the leads. If you don't have zero then don't parallel.

@@LewisLoflin As I said, and also as you do here on the video - transformers are identical. But conenction should be Transformer1-A out to transferomer 2-A out, the same for B. What do you mean by "Measure between terminals when connected on one, should be zero"? As they are in pararell it does not matter where you measure/hook up, on transformer 1 or transformer 2 A&B outs

This is what I was thinking. If you connect the left of transformer 1 to the right of transformer 2, and the right of transformer 1 to the left of transformer 2, this will create a short circuit. There will be a circulating current in the secondary windings of the transformers, heating up both of them. I also do not understand the series connection in this video. If these are identical transformers, then the current direction should be the same for both transformers, right? What I don't understand is why the left terminal of both transformers were connected to earch other. I thought that the currents coming from each transformer will oppose each other. Shouldn't you connect the opposite terminals of the transformers so that the current direction will be followed for both transformers?

I think you are both correct. I was confused too - it does look wrong since you'd expect to connect matching physical terminals on the secondaries to have the transformers in parallel. The only explanation I can see is that the primaries (120V inputs) are wired opposite in the two transformers. That would make the phases of the outputs opposite. It does make the video very confusing. However, the author is correct - if you check the voltage as zero you make the final connection you will be safe.

@@richardwebber1665 Same problem with me. In the physical sense, it can look wrong which is why I use a meter.

Without knowing the voltages involved I would say no. How are you connecting the transformers? If in series then the center tap should be where the two transformers are connected together.

@@LewisLoflin So basically I want to connect 2 transformers in series like you did for a higher voltage, but I need to use the CT(s) to feed into my existing circuit board. in your example it would be T1CT and T2CT, can these be joined together and used as 1 main CT? thx

@@peternotpeter If the secondaries are connected in series and properly phased then we have three taps - the original twp plus the connection between secondaries.

@@LewisLoflin So, just to be clear if the transformers in series are properly phased, I can join both center taps together from both transformers to use as one main center tap?

Properly phased for parallel, I think so.