Hi everyone,
I have come across this term for the first time and I am having a lot of trouble understanding this completely, so I could use help.
We are making cabinets per UL508A and we have (amongst other stuff) two 5kVA transformers in our cabinets. They are the same (prim, 240x480V, sec. 120/240VAC, in datasheet it says `no taps`), but used in different ways. Both have 480VAC on the primary side, but one is connected so it has only 120VAC on the secondary, and the other one is connected for 240/120V (three wire operation).
I sized both primary and secondary fuses per table 35.1 in UL508A, and than specified primary and secondary conductors per table 28.1. I saw paragraph 32.4.4 and then started wondering if these transformers could be considered tapped transformers and is there a way to use smaller gauge internal conductors?
I found a lot of information online about tapped conductors per NEC, and the more I read about it the more I get confused.
Could any transformer that has multiple primary or secondary windings be considered a tapped transformer? Or what are other factors that should be taken into account (keeping in mind that primary and secondary protection, as well as the transformer itself are always inside our main cabinets)?
Thanks!
I have come across this term for the first time and I am having a lot of trouble understanding this completely, so I could use help.
We are making cabinets per UL508A and we have (amongst other stuff) two 5kVA transformers in our cabinets. They are the same (prim, 240x480V, sec. 120/240VAC, in datasheet it says `no taps`), but used in different ways. Both have 480VAC on the primary side, but one is connected so it has only 120VAC on the secondary, and the other one is connected for 240/120V (three wire operation).
I sized both primary and secondary fuses per table 35.1 in UL508A, and than specified primary and secondary conductors per table 28.1. I saw paragraph 32.4.4 and then started wondering if these transformers could be considered tapped transformers and is there a way to use smaller gauge internal conductors?
I found a lot of information online about tapped conductors per NEC, and the more I read about it the more I get confused.
Could any transformer that has multiple primary or secondary windings be considered a tapped transformer? Or what are other factors that should be taken into account (keeping in mind that primary and secondary protection, as well as the transformer itself are always inside our main cabinets)?
Thanks!
