Help: Possible Power Jack transformer

25 minutes ago, christianrodher said:

It seems like a power jack transformer.

It is 😉

25 minutes ago, christianrodher said:

Can this be use to split a 240v single phase AC output into 2 lines of 120v (split phase)?

Yes, though it's only going to be good for 2-3kw max before it exceeds 80-90C.

25 minutes ago, christianrodher said:

If so can anyone help me with the wiring diagram.

Ignore the big red and black leads; that's the transformer "battery" side (intended for a 48vDC PJ inverter, judging by the label.) You'll probably want to put tape over them or something to prevent them from shorting out.

While I'm not 100% sure (PJ is very unpredictable!), the smaller leads on the other side of the transformer should be "L1 N L2", with the yellow lead being the Neutral line.  The small red/black wires here can go to 240vAC, and you'll have somewhere between 115-130vAC between red/yellow, and the same across yellow/black.

These transformers are notoriously imbalanced...so don't expect perfectly balanced phases.

49 minutes ago, christianrodher said:

If not what is the use of this transformer?

It's a transformer used in 48vDC "8kw" PJ (or "15kw" U-Power) inverters...which will only do 2-3kw before overheating.

Thanks for the fast reply!

11 minutes ago, Sid Genetry Solar said:

While I'm not 100% sure (PJ is very unpredictable!), the smaller leads on the other side of the transformer should be "L1 N L2", with the yellow lead being the Neutral line.  The small red/black wires here can go to 240vAC, and you'll have somewhere between 115-130vAC between red/yellow, and the same across yellow/black.

These transformers are notoriously imbalanced...so don't expect perfectly balanced phases.

So the black (L1 120v), Yellow (N) and the Red (L2 120v) are outputs. The big ones are 48vDC. So where do I input the L1 240v and N ?

1 hour ago, christianrodher said:

Thanks for the fast reply!

So the black (L1 120v), Yellow (N) and the Red (L2 120v) are outputs. The big ones are 48vDC. So where do I input the L1 240v and N ?

If used for an inverter, yes, that is the hookup.

But if you're using it as an autoformer, then wire it up as I described above:

1 hour ago, Sid Genetry Solar said:

Ignore the big red and black leads; that's the transformer "battery" side (intended for a 48vDC PJ inverter, judging by the label.) You'll probably want to put tape over them or something to prevent them from shorting out.

While I'm not 100% sure (PJ is very unpredictable!), the smaller leads on the other side of the transformer should be "L1 N L2", with the yellow lead being the Neutral line.  The small red/black wires here can go to 240vAC, and you'll have somewhere between 115-130vAC between red/yellow, and the same across yellow/black.

Small red/black wires go to "L1 / N 240v" (if you're using single-phase vernacular)...assuming that's how PJ wound this particular transformer.

It's rather important to keep your vernacular straight; a single-phase 240v system is the same as a 120v single-phase system: L and N.

However, those exact same "L / N" wires are "L1 / L2" if you are working with a split-phase 240v system.  Neutral becomes the middle wire generated by the transformer--though if you're planning on grounding anything here, use simple common electrical sense to avoid half the transformer out through grounding.

I dont understand. I made a horrible diagram that shows what I want to acomplish. I dont know where to connect the "black" and "yellow" wires coming out of the inverter AC output to the transformer.

To the small red and black wires of the transformer.

It's a transformer used in 48vDC "8kw" PJ (or "15kw" U-Power) inverters...which will only do 2-3kw before overheating.

To the small red and black wires of the transformer  AS3  

The load to the  small red and black wires  when use as an  autotransformer  must be less than 3000 watts or bad  thing will happen .  

5 hours ago, InPhase said:

To the small red and black wires of the transformer.

<fileStore.core_Attachment>/monthly_2021_11/ACD92683-9A0F-494E-A3CC-B0D5A182A506.jpeg.dcd8f72594bbe6b8cf6bf5265cb72486.jpeg

the 240 out of the inverter goes to the marked small red and black wires located in the black wire? 

This is my first time wiring a transformer. Im trying to understand the instructions. But if I use the small red and black wires to input the 240v single phase (L,N). How can those same wires be the output L1 and L2 of 120v and the Yellow be N.

This is my first time wiring a transformer. Im trying to understand the instructions. But if I use the small red and black wires to input the 240v single phase (L,N). How can those same wires be the output L1 and L2 of 120v and the Yellow be N.

Look at your diagram  and  the load connected  to the breaker box  red wire and  yellow N  will give 120 v  and a load connected to the black wire and the yellow N  will give 120v also  but if you connect the load to the red and black wire then  you have 240 v  like what is output of the solar inverter .    Should use a kill-a watt meter to make sure your load  is less than 3000  watt or doing this as an autotransformer is very dangerous .   

From your diagram  the yellow neutral  output wire  from the solar inverter  go to the  red wire of the breaker box  NOT the  yellow N  of the breaker box  and the  black wire output of the solar inverter go to the small black wire of the breaker box which is the same as the small black wire of the transformer .  The  2 large red and  black wire is taped up and not use and  NOT  connected . 

Your original diagram  .   The solar inverter yellow go to the red  small wire of the AS3 transformer .   The red wire of the breaker box and the yellow  N of the breaker box give 120v .     The  yellow wire of the solar inverter and the black wire of the solar inverter  give  240 vac .   

3 hours ago, christianrodher said:

the 240 out of the inverter goes to the marked small red and black wires located in the black wire?

Ha, no.  That's a current sense device, you'll blow it up very quickly with 240v.

Try this:

<img class="ipsImage ipsImage_thumbnailed" data-fileid="921" data-ratio="97.28" width="661" alt="image.png.4576a45053105019d44e11cfe82dbcc8.png" data-src="/monthly_2021_11/image.png.4576a45053105019d44e11cfe82dbcc8.png" src="/applications/core/interface/js/spacer.png" />

Being a Chinese inverter, I doubt the ground point will have much to do with anything.  The serious issue comes in if it's tied/coupled to the inverter's "Neutral", which is being used as L2.  Shorting this L2 to the new Neutral generated by the transformer CAN cause serious issues, and it's best left unconnected IMO.

Whoops, I see this is a big transformer based inverter, not a HF inverter so the below doesn't apply.  That is all only for HF inverters, but it's still a good read so I'll leave it for posterity.

A low wattage 120 (or 240v, as appropriate) incandescent (the hot wire type) light bulb between the earth terminal and one of the AC output wires of the inverter is one way to test if it is safe to tie one of the AC output wires to earth and declare it neutral.  If the bulb lights even dimly, it is not safe to tie that AC output wire to earth.  With the bulb in place measure the AC voltage across the bulb.  It should be close to 0 volts.  If not, it is not safe to tie that AC output wire to earth.  Repeat the tests with the other AC output wire.  You can not measure the voltage without the bulb or a decent load in place as there definitely will be leakage voltage between the chassis earth and the AC output wires giving an approx 1/2 AC voltage reading.

Be especially wary of 120VAC single phase inverters that have a terminal strip and have 4 terminals.  They are almost certainly 120/240 split designs that are simply being run at low output voltage.  What you have on the terminal block is chassis earth, L1, 'neutral', L2.  The neutral terminal is at half line voltage (60VAC) with respect to the chassis earth terminal.  'Reliable Electric' had a few models like that.  Taking L1 or L2 to earth will blow transistors at power up of the inverter.  I have seen this style of inverter being sold as '240V' single phase into Europe / Australia / NZ etc, ie '240V' only countries.  The same caution applies there.  Connecting either of the AC output wires to earth to establish neutral = bang.

These particular designs aren't intrinsically unsafe.  A correctly installed RCD will still trip as current can flow from L1/L2 to the physical earth (ie a return path other than L1/L2) if you have tied the earth terminal to ... the earth.

Ultimately these things are not supposed to be wired up to premises wiring, even the ones that have terminal strips, but a technically competent person can ensure things are safe and don't go bang.

14 hours ago, Sid Genetry Solar said:

Ha, no.  That's a current sense device, you'll blow it up very quickly with 240v.

 

 

Try this:

 

<a data-fileext="png" data-fileid="921" href="/monthly_2021_11/image.png.4576a45053105019d44e11cfe82dbcc8.png" rel="" title="Enlarge image">

//content.invisioncic.com/g308908/monthly_2021_11/image.png.4576a45053105019d44e11cfe82dbcc8.png

Being a Chinese inverter, I doubt the ground point will have much to do with anything.  The serious issue comes in if it's tied/coupled to the inverter's "Neutral", which is being used as L2.  Shorting this L2 to the new Neutral generated by the transformer CAN cause serious issues, and it's best left unconnected IMO.

 

Thanks you very much, this forum is great!!! I will try this. Is the max safe watts of 2500-3000 is pre phase or total?