Are Hammond 2-300 series ratings misleading?

[regal]

Example 369JX 50 500V C.T. @ 69ma , now in school I was taught that the CT voltage rating was for total voltage ie 250-0-250 with 69 mA at each secondary. Yet anyone using this with say a 5AR4 recitifer at around 250V DC after rectification is only getting 69 ma of current capability, shouldn't they be getting 69x2=138mA ?

[megajocke]

It's the low power factor of the rectifier that causes it. Each winding half needs to support about the same RMS current as the output average current from the rectifier. Transformer manufacturers usually have application notes with formulas. For the commonly used in solid-state equipment 4-diode bridge circuit the RMS current on the input is about 1.8 times the average output current.

So it's not that the transformer has misleading ratings, it's just that rectifiers demand a bit more from the transformer than most think.