Is that a center tap tranformer just labelled differently?












1












$begingroup$


my transformer has a secondary winding of 0 - 12v - 24v



Is it just labelled differently and is it really a center tap where 12v would be the center, 0 would be -12v and 24 would be 12v?



Thanks!



transformer






transformer identification







share|improve this question









$endgroup$












  • $begingroup$
    It's not an autotransformer is it (basically just a big inductor with multiple output taps)? You can check by measuring resistance to see if the 0V and 0V are electrically connected to each other
    $endgroup$
    – Toor
    6 hours ago












  • $begingroup$
    @Toor thanks will check, in the mean time their website in french clearly makes a distinction between a regular transformer and autotransformer and the label says "transformer" so I would guess this is not an autotransformer. Getting the multimeter..
    $endgroup$
    – Mike Gleason jr Couturier
    6 hours ago










  • $begingroup$
    @Toor Can confirm: 0 and 0 are not connected to each other.. 0 and 12 and 24 are on the secondary, obviously 0 and 220 are on the primary side
    $endgroup$
    – Mike Gleason jr Couturier
    6 hours ago






  • 3




    $begingroup$
    Yeah, so a normal center-tap transformer just labelled specifically for its intended use then.
    $endgroup$
    – Toor
    5 hours ago








  • 2




    $begingroup$
    You can. Just note that one half-winding will be loaded a more than the other half and will affect both voltage outputs.
    $endgroup$
    – Toor
    5 hours ago


















1












$begingroup$


my transformer has a secondary winding of 0 - 12v - 24v



Is it just labelled differently and is it really a center tap where 12v would be the center, 0 would be -12v and 24 would be 12v?



Thanks!



transformer






transformer identification







share|improve this question









$endgroup$












  • $begingroup$
    It's not an autotransformer is it (basically just a big inductor with multiple output taps)? You can check by measuring resistance to see if the 0V and 0V are electrically connected to each other
    $endgroup$
    – Toor
    6 hours ago












  • $begingroup$
    @Toor thanks will check, in the mean time their website in french clearly makes a distinction between a regular transformer and autotransformer and the label says "transformer" so I would guess this is not an autotransformer. Getting the multimeter..
    $endgroup$
    – Mike Gleason jr Couturier
    6 hours ago










  • $begingroup$
    @Toor Can confirm: 0 and 0 are not connected to each other.. 0 and 12 and 24 are on the secondary, obviously 0 and 220 are on the primary side
    $endgroup$
    – Mike Gleason jr Couturier
    6 hours ago






  • 3




    $begingroup$
    Yeah, so a normal center-tap transformer just labelled specifically for its intended use then.
    $endgroup$
    – Toor
    5 hours ago








  • 2




    $begingroup$
    You can. Just note that one half-winding will be loaded a more than the other half and will affect both voltage outputs.
    $endgroup$
    – Toor
    5 hours ago
















1












1








1





$begingroup$


my transformer has a secondary winding of 0 - 12v - 24v



Is it just labelled differently and is it really a center tap where 12v would be the center, 0 would be -12v and 24 would be 12v?



Thanks!



transformer






transformer identification







share|improve this question









$endgroup$




my transformer has a secondary winding of 0 - 12v - 24v



Is it just labelled differently and is it really a center tap where 12v would be the center, 0 would be -12v and 24 would be 12v?



Thanks!



transformer






transformer identification




transformer identification






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked 6 hours ago









Mike Gleason jr CouturierMike Gleason jr Couturier

34518




34518












  • $begingroup$
    It's not an autotransformer is it (basically just a big inductor with multiple output taps)? You can check by measuring resistance to see if the 0V and 0V are electrically connected to each other
    $endgroup$
    – Toor
    6 hours ago












  • $begingroup$
    @Toor thanks will check, in the mean time their website in french clearly makes a distinction between a regular transformer and autotransformer and the label says "transformer" so I would guess this is not an autotransformer. Getting the multimeter..
    $endgroup$
    – Mike Gleason jr Couturier
    6 hours ago










  • $begingroup$
    @Toor Can confirm: 0 and 0 are not connected to each other.. 0 and 12 and 24 are on the secondary, obviously 0 and 220 are on the primary side
    $endgroup$
    – Mike Gleason jr Couturier
    6 hours ago






  • 3




    $begingroup$
    Yeah, so a normal center-tap transformer just labelled specifically for its intended use then.
    $endgroup$
    – Toor
    5 hours ago








  • 2




    $begingroup$
    You can. Just note that one half-winding will be loaded a more than the other half and will affect both voltage outputs.
    $endgroup$
    – Toor
    5 hours ago




















  • $begingroup$
    It's not an autotransformer is it (basically just a big inductor with multiple output taps)? You can check by measuring resistance to see if the 0V and 0V are electrically connected to each other
    $endgroup$
    – Toor
    6 hours ago












  • $begingroup$
    @Toor thanks will check, in the mean time their website in french clearly makes a distinction between a regular transformer and autotransformer and the label says "transformer" so I would guess this is not an autotransformer. Getting the multimeter..
    $endgroup$
    – Mike Gleason jr Couturier
    6 hours ago










  • $begingroup$
    @Toor Can confirm: 0 and 0 are not connected to each other.. 0 and 12 and 24 are on the secondary, obviously 0 and 220 are on the primary side
    $endgroup$
    – Mike Gleason jr Couturier
    6 hours ago






  • 3




    $begingroup$
    Yeah, so a normal center-tap transformer just labelled specifically for its intended use then.
    $endgroup$
    – Toor
    5 hours ago








  • 2




    $begingroup$
    You can. Just note that one half-winding will be loaded a more than the other half and will affect both voltage outputs.
    $endgroup$
    – Toor
    5 hours ago


















$begingroup$
It's not an autotransformer is it (basically just a big inductor with multiple output taps)? You can check by measuring resistance to see if the 0V and 0V are electrically connected to each other
$endgroup$
– Toor
6 hours ago






$begingroup$
It's not an autotransformer is it (basically just a big inductor with multiple output taps)? You can check by measuring resistance to see if the 0V and 0V are electrically connected to each other
$endgroup$
– Toor
6 hours ago














$begingroup$
@Toor thanks will check, in the mean time their website in french clearly makes a distinction between a regular transformer and autotransformer and the label says "transformer" so I would guess this is not an autotransformer. Getting the multimeter..
$endgroup$
– Mike Gleason jr Couturier
6 hours ago




$begingroup$
@Toor thanks will check, in the mean time their website in french clearly makes a distinction between a regular transformer and autotransformer and the label says "transformer" so I would guess this is not an autotransformer. Getting the multimeter..
$endgroup$
– Mike Gleason jr Couturier
6 hours ago












$begingroup$
@Toor Can confirm: 0 and 0 are not connected to each other.. 0 and 12 and 24 are on the secondary, obviously 0 and 220 are on the primary side
$endgroup$
– Mike Gleason jr Couturier
6 hours ago




$begingroup$
@Toor Can confirm: 0 and 0 are not connected to each other.. 0 and 12 and 24 are on the secondary, obviously 0 and 220 are on the primary side
$endgroup$
– Mike Gleason jr Couturier
6 hours ago




3




3




$begingroup$
Yeah, so a normal center-tap transformer just labelled specifically for its intended use then.
$endgroup$
– Toor
5 hours ago






$begingroup$
Yeah, so a normal center-tap transformer just labelled specifically for its intended use then.
$endgroup$
– Toor
5 hours ago






2




2




$begingroup$
You can. Just note that one half-winding will be loaded a more than the other half and will affect both voltage outputs.
$endgroup$
– Toor
5 hours ago






$begingroup$
You can. Just note that one half-winding will be loaded a more than the other half and will affect both voltage outputs.
$endgroup$
– Toor
5 hours ago












3 Answers
3






active

oldest

votes


















3












$begingroup$

Not necessarily. If the transformer is rated to produce full output from either the 12V tap or the 24V tap, it could be that the winding from the 12 to 24V terminals is of a finer gage, since the current that could be drawn from the 24V tap would be half that you could draw at 12V. This you can determine by comparing the resistance of the 0-12 and 12-24 windings.



Would that matter for using it as a center-tapped +/- 12V transformer? Not much, the terminal voltage at the high side would be fractionally lower under load, but the overall heating compared to drawing the full power at a single tap would actually be less.






share|improve this answer









$endgroup$













  • $begingroup$
    I get 1 ohm resistence between 0 and 12, 1 ohm between 12 and 24 and 2 ohms between 0 and 24... So I guess this really is a center tap?
    $endgroup$
    – Mike Gleason jr Couturier
    5 hours ago






  • 1




    $begingroup$
    I'd think so. While you can get more out of a given core (since you have to get all the windings through a fixed window size) by fine-tuning the wire sizes, there's the additional cost of winding different wire sizes, so keeping the windings the same is likely cheaper. More effective still for a 12V OR 24V secondary is to have two separate winding that can then be connected series or parallel to maximize winding utilization.
    $endgroup$
    – Phil G
    5 hours ago



















2












$begingroup$

I would guess that yes, it is just a regular center tap transformer. Assuming that's the case:



The outputs will be AC, so -12V doesn't really have any meaning. The 12V here will be 12V AC, and the 24 will be 24V AC.



If you make the center tap 0, then "LABEL 0" will be 12V, and "LABEL 24" will also be 12V (but they will be out of phase with each other).



Based on the labeling, I think it's fairly certain that this is a regular transformer, but I would do some continuity tests just to make sure.






share|improve this answer









$endgroup$













  • $begingroup$
    Thanks for your answer, As I said above in a comment: 0 and 0 are not connected to each other.. 0 and 12 and 24 are connected on the secondary, 0 and 220 are connected on the primary side. (connected I mean near 0 resistance)
    $endgroup$
    – Mike Gleason jr Couturier
    5 hours ago



















2












$begingroup$

0V is arbitrary as it is floating secondary centre-tapped coil.



so you can relabel with 3 choices;



0     : 12Vac : 24Vac   

12Vac : 0V    : 12Vac   +180 deg         

24Vac : 12Vac :  0V





share|improve this answer









$endgroup$













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    3 Answers
    3






    active

    oldest

    votes








    3 Answers
    3






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    3












    $begingroup$

    Not necessarily. If the transformer is rated to produce full output from either the 12V tap or the 24V tap, it could be that the winding from the 12 to 24V terminals is of a finer gage, since the current that could be drawn from the 24V tap would be half that you could draw at 12V. This you can determine by comparing the resistance of the 0-12 and 12-24 windings.



    Would that matter for using it as a center-tapped +/- 12V transformer? Not much, the terminal voltage at the high side would be fractionally lower under load, but the overall heating compared to drawing the full power at a single tap would actually be less.






    share|improve this answer









    $endgroup$













    • $begingroup$
      I get 1 ohm resistence between 0 and 12, 1 ohm between 12 and 24 and 2 ohms between 0 and 24... So I guess this really is a center tap?
      $endgroup$
      – Mike Gleason jr Couturier
      5 hours ago






    • 1




      $begingroup$
      I'd think so. While you can get more out of a given core (since you have to get all the windings through a fixed window size) by fine-tuning the wire sizes, there's the additional cost of winding different wire sizes, so keeping the windings the same is likely cheaper. More effective still for a 12V OR 24V secondary is to have two separate winding that can then be connected series or parallel to maximize winding utilization.
      $endgroup$
      – Phil G
      5 hours ago
















    3












    $begingroup$

    Not necessarily. If the transformer is rated to produce full output from either the 12V tap or the 24V tap, it could be that the winding from the 12 to 24V terminals is of a finer gage, since the current that could be drawn from the 24V tap would be half that you could draw at 12V. This you can determine by comparing the resistance of the 0-12 and 12-24 windings.



    Would that matter for using it as a center-tapped +/- 12V transformer? Not much, the terminal voltage at the high side would be fractionally lower under load, but the overall heating compared to drawing the full power at a single tap would actually be less.






    share|improve this answer









    $endgroup$













    • $begingroup$
      I get 1 ohm resistence between 0 and 12, 1 ohm between 12 and 24 and 2 ohms between 0 and 24... So I guess this really is a center tap?
      $endgroup$
      – Mike Gleason jr Couturier
      5 hours ago






    • 1




      $begingroup$
      I'd think so. While you can get more out of a given core (since you have to get all the windings through a fixed window size) by fine-tuning the wire sizes, there's the additional cost of winding different wire sizes, so keeping the windings the same is likely cheaper. More effective still for a 12V OR 24V secondary is to have two separate winding that can then be connected series or parallel to maximize winding utilization.
      $endgroup$
      – Phil G
      5 hours ago














    3












    3








    3





    $begingroup$

    Not necessarily. If the transformer is rated to produce full output from either the 12V tap or the 24V tap, it could be that the winding from the 12 to 24V terminals is of a finer gage, since the current that could be drawn from the 24V tap would be half that you could draw at 12V. This you can determine by comparing the resistance of the 0-12 and 12-24 windings.



    Would that matter for using it as a center-tapped +/- 12V transformer? Not much, the terminal voltage at the high side would be fractionally lower under load, but the overall heating compared to drawing the full power at a single tap would actually be less.






    share|improve this answer









    $endgroup$



    Not necessarily. If the transformer is rated to produce full output from either the 12V tap or the 24V tap, it could be that the winding from the 12 to 24V terminals is of a finer gage, since the current that could be drawn from the 24V tap would be half that you could draw at 12V. This you can determine by comparing the resistance of the 0-12 and 12-24 windings.



    Would that matter for using it as a center-tapped +/- 12V transformer? Not much, the terminal voltage at the high side would be fractionally lower under load, but the overall heating compared to drawing the full power at a single tap would actually be less.







    share|improve this answer












    share|improve this answer



    share|improve this answer










    answered 6 hours ago









    Phil GPhil G

    2,5571412




    2,5571412












    • $begingroup$
      I get 1 ohm resistence between 0 and 12, 1 ohm between 12 and 24 and 2 ohms between 0 and 24... So I guess this really is a center tap?
      $endgroup$
      – Mike Gleason jr Couturier
      5 hours ago






    • 1




      $begingroup$
      I'd think so. While you can get more out of a given core (since you have to get all the windings through a fixed window size) by fine-tuning the wire sizes, there's the additional cost of winding different wire sizes, so keeping the windings the same is likely cheaper. More effective still for a 12V OR 24V secondary is to have two separate winding that can then be connected series or parallel to maximize winding utilization.
      $endgroup$
      – Phil G
      5 hours ago


















    • $begingroup$
      I get 1 ohm resistence between 0 and 12, 1 ohm between 12 and 24 and 2 ohms between 0 and 24... So I guess this really is a center tap?
      $endgroup$
      – Mike Gleason jr Couturier
      5 hours ago






    • 1




      $begingroup$
      I'd think so. While you can get more out of a given core (since you have to get all the windings through a fixed window size) by fine-tuning the wire sizes, there's the additional cost of winding different wire sizes, so keeping the windings the same is likely cheaper. More effective still for a 12V OR 24V secondary is to have two separate winding that can then be connected series or parallel to maximize winding utilization.
      $endgroup$
      – Phil G
      5 hours ago
















    $begingroup$
    I get 1 ohm resistence between 0 and 12, 1 ohm between 12 and 24 and 2 ohms between 0 and 24... So I guess this really is a center tap?
    $endgroup$
    – Mike Gleason jr Couturier
    5 hours ago




    $begingroup$
    I get 1 ohm resistence between 0 and 12, 1 ohm between 12 and 24 and 2 ohms between 0 and 24... So I guess this really is a center tap?
    $endgroup$
    – Mike Gleason jr Couturier
    5 hours ago




    1




    1




    $begingroup$
    I'd think so. While you can get more out of a given core (since you have to get all the windings through a fixed window size) by fine-tuning the wire sizes, there's the additional cost of winding different wire sizes, so keeping the windings the same is likely cheaper. More effective still for a 12V OR 24V secondary is to have two separate winding that can then be connected series or parallel to maximize winding utilization.
    $endgroup$
    – Phil G
    5 hours ago




    $begingroup$
    I'd think so. While you can get more out of a given core (since you have to get all the windings through a fixed window size) by fine-tuning the wire sizes, there's the additional cost of winding different wire sizes, so keeping the windings the same is likely cheaper. More effective still for a 12V OR 24V secondary is to have two separate winding that can then be connected series or parallel to maximize winding utilization.
    $endgroup$
    – Phil G
    5 hours ago













    2












    $begingroup$

    I would guess that yes, it is just a regular center tap transformer. Assuming that's the case:



    The outputs will be AC, so -12V doesn't really have any meaning. The 12V here will be 12V AC, and the 24 will be 24V AC.



    If you make the center tap 0, then "LABEL 0" will be 12V, and "LABEL 24" will also be 12V (but they will be out of phase with each other).



    Based on the labeling, I think it's fairly certain that this is a regular transformer, but I would do some continuity tests just to make sure.






    share|improve this answer









    $endgroup$













    • $begingroup$
      Thanks for your answer, As I said above in a comment: 0 and 0 are not connected to each other.. 0 and 12 and 24 are connected on the secondary, 0 and 220 are connected on the primary side. (connected I mean near 0 resistance)
      $endgroup$
      – Mike Gleason jr Couturier
      5 hours ago
















    2












    $begingroup$

    I would guess that yes, it is just a regular center tap transformer. Assuming that's the case:



    The outputs will be AC, so -12V doesn't really have any meaning. The 12V here will be 12V AC, and the 24 will be 24V AC.



    If you make the center tap 0, then "LABEL 0" will be 12V, and "LABEL 24" will also be 12V (but they will be out of phase with each other).



    Based on the labeling, I think it's fairly certain that this is a regular transformer, but I would do some continuity tests just to make sure.






    share|improve this answer









    $endgroup$













    • $begingroup$
      Thanks for your answer, As I said above in a comment: 0 and 0 are not connected to each other.. 0 and 12 and 24 are connected on the secondary, 0 and 220 are connected on the primary side. (connected I mean near 0 resistance)
      $endgroup$
      – Mike Gleason jr Couturier
      5 hours ago














    2












    2








    2





    $begingroup$

    I would guess that yes, it is just a regular center tap transformer. Assuming that's the case:



    The outputs will be AC, so -12V doesn't really have any meaning. The 12V here will be 12V AC, and the 24 will be 24V AC.



    If you make the center tap 0, then "LABEL 0" will be 12V, and "LABEL 24" will also be 12V (but they will be out of phase with each other).



    Based on the labeling, I think it's fairly certain that this is a regular transformer, but I would do some continuity tests just to make sure.






    share|improve this answer









    $endgroup$



    I would guess that yes, it is just a regular center tap transformer. Assuming that's the case:



    The outputs will be AC, so -12V doesn't really have any meaning. The 12V here will be 12V AC, and the 24 will be 24V AC.



    If you make the center tap 0, then "LABEL 0" will be 12V, and "LABEL 24" will also be 12V (but they will be out of phase with each other).



    Based on the labeling, I think it's fairly certain that this is a regular transformer, but I would do some continuity tests just to make sure.







    share|improve this answer












    share|improve this answer



    share|improve this answer










    answered 6 hours ago









    DrewDrew

    1,8561513




    1,8561513












    • $begingroup$
      Thanks for your answer, As I said above in a comment: 0 and 0 are not connected to each other.. 0 and 12 and 24 are connected on the secondary, 0 and 220 are connected on the primary side. (connected I mean near 0 resistance)
      $endgroup$
      – Mike Gleason jr Couturier
      5 hours ago


















    • $begingroup$
      Thanks for your answer, As I said above in a comment: 0 and 0 are not connected to each other.. 0 and 12 and 24 are connected on the secondary, 0 and 220 are connected on the primary side. (connected I mean near 0 resistance)
      $endgroup$
      – Mike Gleason jr Couturier
      5 hours ago
















    $begingroup$
    Thanks for your answer, As I said above in a comment: 0 and 0 are not connected to each other.. 0 and 12 and 24 are connected on the secondary, 0 and 220 are connected on the primary side. (connected I mean near 0 resistance)
    $endgroup$
    – Mike Gleason jr Couturier
    5 hours ago




    $begingroup$
    Thanks for your answer, As I said above in a comment: 0 and 0 are not connected to each other.. 0 and 12 and 24 are connected on the secondary, 0 and 220 are connected on the primary side. (connected I mean near 0 resistance)
    $endgroup$
    – Mike Gleason jr Couturier
    5 hours ago











    2












    $begingroup$

    0V is arbitrary as it is floating secondary centre-tapped coil.



    so you can relabel with 3 choices;



    0     : 12Vac : 24Vac   
    
12Vac : 0V    : 12Vac   +180 deg         
    
24Vac : 12Vac :  0V





    share|improve this answer









    $endgroup$


















      2












      $begingroup$

      0V is arbitrary as it is floating secondary centre-tapped coil.



      so you can relabel with 3 choices;



      0     : 12Vac : 24Vac   
      
12Vac : 0V    : 12Vac   +180 deg         
      
24Vac : 12Vac :  0V





      share|improve this answer









      $endgroup$
















        2












        2








        2





        $begingroup$

        0V is arbitrary as it is floating secondary centre-tapped coil.



        so you can relabel with 3 choices;



        0     : 12Vac : 24Vac   
        
12Vac : 0V    : 12Vac   +180 deg         
        
24Vac : 12Vac :  0V





        share|improve this answer









        $endgroup$



        0V is arbitrary as it is floating secondary centre-tapped coil.



        so you can relabel with 3 choices;



        0     : 12Vac : 24Vac   
        
12Vac : 0V    : 12Vac   +180 deg         
        
24Vac : 12Vac :  0V






        share|improve this answer












        share|improve this answer



        share|improve this answer










        answered 5 hours ago









        Sunnyskyguy EE75Sunnyskyguy EE75

        67.4k22397




        67.4k22397






























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