Thanks for sharing this. After watching your video a few times, I took two identical, unmarked salvaged transformers, each with multiple secondary windings, and successfully wired them together to produce one center-tapped transformer that's perfect for a 52V split-rail linear power supply!
Best video on this topic I've found so far. Thank you for posting. I'm confused about phasing in parallel transformers (simple CT Xfrmrs like your example). Does polarity/phasing matter when connecting secondaries? (no polarity to AC but Secondary winding direction/phasing).
i love those little digital volt meters... 🔔 they do more than the very 1st ones and changing the world of test equipment thinking...:) now the sky is the limit. nice info..👍👍👍
So called Magnetic amplifiers are annother very interesting way of connecting transforners... Pair of transformers... Wired up so one side in series to a DC control circuit, and other side in series with ac source and ac load. Small changes to DC control current can adjust how saturated the transformer core gets, which then alters the current on the ac side.
I've always wondered if you could stack different outputs from computer power supplies to increase voltage and make a more versatile bench power supply. My guess is if they have more than one secondary coil within the supply they might be stackable.
Thanks Lewis - I've never stacked transformers before. Good info. I enjoy your videos, very clear, step by step. The only place you lost me was @ 7:30 and the "1.41"multiplier. I don't understand where you got that 1.41 number from? If you've covered it in a previous video, I guess I missed it. Could you refresh my memory? Thanks again!
Wouldn't putting two transformers in series be hooking up transformer #1 secondaries to transformer #2 primaries and the end result voltage would be doubled?
@@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.
first thank you very much for the informations . Is there any difference or advantges if i connect the 2 in parrallel after the bridge diode ?. in other way if i connect them in PARALLEL in DC mode rather than AC mode to get more amps .
I guess your high AC input is not in the same pin for each trans (you connect both left sides as a serial connection), so N and L are not going to the same input pin for each trans, I guess it is better explained in the video of another channel czcams.com/video/ejWjR0laKo0/video.html
I think this is wrong... I tried your approach for parallel (around 3:20) and it resulted with heavy transformer temperature rising fast + abnormal voltages. I said, wait, something is wrong here. If you have 2 identical transformers and want to hook up them in PARALLEL, you need to hook up left out to left out frokm 2nd transformer, right out to right out from 2nd transformer and measure between left and right (no matter on which one transformer). I did that and it's OK and it's parallel connection. A to A, B to B. Like any other resistor, capacitor, anything else. Because my transformers had also 6.3V for heaters, I also jumpered them the same way and it's also good.
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.
a bit confusing...no and need to include the letter T, ta1 tb2...we know what they are; drawings on a piece of paper always help a great deal too; thanks
Excellent, I need to make an 800 volts DC power supply. I will use two isolation trasformers from 110 volts to 220 conecting the outputs in series plus a voltage doubler, I regulate the output voltage using my variac in the 110 volts input. Best Regards.
Hi Lewis, thank you for this video. I need to replace a transformer in a guitar amp with two transformers to give me the same voltage. Can the center taps of both transformers be connected together to replace the original center tap before it gets rectified?
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?
Thanks for sharing this. After watching your video a few times, I took two identical, unmarked salvaged transformers, each with multiple secondary windings, and successfully wired them together to produce one center-tapped transformer that's perfect for a 52V split-rail linear power supply!
thanks for the video. it answered questions i've been having about this.
Best video on this topic I've found so far. Thank you for posting. I'm confused about phasing in parallel transformers (simple CT Xfrmrs like your example). Does polarity/phasing matter when connecting secondaries? (no polarity to AC but Secondary winding direction/phasing).
i love those little digital volt meters... 🔔 they do more than the very 1st ones and changing the world of test equipment thinking...:) now the sky is the limit. nice info..👍👍👍
So called Magnetic amplifiers are annother very interesting way of connecting transforners...
Pair of transformers... Wired up so one side in series to a DC control circuit, and other side in series with ac source and ac load. Small changes to DC control current can adjust how saturated the transformer core gets, which then alters the current on the ac side.
I've always wondered if you could stack different outputs from computer power supplies to increase voltage and make a more versatile bench power supply. My guess is if they have more than one secondary coil within the supply they might be stackable.
Very nice videooo
I'll use this for educational purposes, thanks
You are welcome.
Thanks Lewis - I've never stacked transformers before. Good info.
I enjoy your videos, very clear, step by step.
The only place you lost me was @ 7:30 and the "1.41"multiplier. I don't understand where you got that 1.41 number from? If you've covered it in a previous video, I guess I missed it. Could you refresh my memory?
Thanks again!
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.
If you parallel one of them in the incorrect phase on the secondary will that create a load and heat the transformers or will it just give you zero?
Fry the transformers.
Wouldn't putting two transformers in series be hooking up transformer #1 secondaries to transformer #2 primaries and the end result voltage would be doubled?
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.
I want to hook 3 tig welders up in delta 120 deg off each one would you know how to wire them to make a electric arc furnace with 3 electrodes?
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.
first thank you very much for the informations .
Is there any difference or advantges if i connect the 2 in parrallel after the bridge diode ?.
in other way if i connect them in PARALLEL in DC mode rather than AC mode to get more amps .
Connecting in parallel at the AC side adds the amps. But the zero test between the two transformers must be done first.
I guess your high AC input is not in the same pin for each trans (you connect both left sides as a serial connection), so N and L are not going to the same input pin for each trans, I guess it is better explained in the video of another channel czcams.com/video/ejWjR0laKo0/video.html
Do they have to be identical transformers or does it not matter
If in parallel then yes. If in series max current is limited to the smallest transformer.
I think this is wrong... I tried your approach for parallel (around 3:20) and it resulted with heavy transformer temperature rising fast + abnormal voltages. I said, wait, something is wrong here. If you have 2 identical transformers and want to hook up them in PARALLEL, you need to hook up left out to left out frokm 2nd transformer, right out to right out from 2nd transformer and measure between left and right (no matter on which one transformer). I did that and it's OK and it's parallel connection. A to A, B to B. Like any other resistor, capacitor, anything else. Because my transformers had also 6.3V for heaters, I also jumpered them the same way and it's also good.
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.
a bit confusing...no
and need to include the letter T, ta1 tb2...we know what they are; drawings on a piece of paper always help a great deal too; thanks
Excellent, I need to make an 800 volts DC power supply.
I will use two isolation trasformers from 110 volts to 220 conecting the outputs in series plus a voltage doubler, I regulate the output voltage using my variac in the 110 volts input.
Best Regards.
Hi Lewis, thank you for this video. I need to replace a transformer in a guitar amp with two transformers to give me the same voltage. Can the center taps of both transformers be connected together to replace the original center tap before it gets rectified?
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.