Transformer Wiring?

[mksj]

The transformer output in this application is most likely floating relative to ground/neutral, and this is then rectified for DC, so there is no need to connect one leg of the transformer's secondary output to neutral. You would use the replacement transformer and wire it the same as the original one it replaced. It outputs single phase 120VAC which is just stepping down the voltage. DC output may be referenced to chassis ground through a center tapped transformer on the secondary or the negative DC rail in certain designs, but this is not applicable in this transformer.