Failed toroidal transformer

[Neale]

New transformer fitted and all working again. I bought a 2x45V 625VA toroidal from Rapid Online. Off load, it gives 50V AC per winding, partly because it has a 230V primary and my mains measures (today, anyway) 241V, and partly, I assume, to allow for voltage drop on load to bring it down to the nominal output value. Off load and connected to rectifier/capacitor, it gives around 68V DC. I haven't measured DC voltage on load as this is somewhat difficult to do, but I did connect the control box to the mains via a power monitor, just out of interest. I have two NEMA23 motors, one driving the relatively light MDF gantry and one for Y. Max load while cutting (light cuts in some old oak) and 500mm/min was around 120W, full rapid speed (but that's only 900mm/min) around 160W. Quiescent (nothing moving) is around 40W. I don't think that the transformer is being over-stretched, but the intention is to move this to Mk2 router when complete and it's been sized more for that.

Anyway, I thought that a few actual measurements might be of interest.

[Clive S]

Neale glad you managed to change it, happy cutting