The data sheet doesn't specifically mention capacitance or VA rating.
Its rated for outputting 480W continuosly. Its a switch mode power supply with active power factor correction. At 230VAC, the Power factor is greater than 0.95 typically and at 115VAC its greater than 0.99 typically. Typical input current is 6.5A/115VAC 3.5A/230VAC
I'm not certain how to calculate the VA rating here but, i guess it is
Apparent Power = Real Power/ power factor = Vin_rms * Iin_rms / PF = 230 * 3.5 / 0.95 = 847 VA at 230V
= 115 * 6.5 / 0.99 = 755 VA at 115 V
With regards to calculating fuse requirements, I have found a guide here Documents | SCHURTER
It talks about calculating the I2t value of the fuse. There are some different V vs I waves forms but it says the most common is the normal decay curve. It gives the formula
I2t = 0.5 * Ipeak2 * timeConstant
If the inrush current lasts for 0.5 to 1 cycle length so at 50Hz, thats 1/50 of a second. Would this be 5 time constants or only one? ie, would I use
I2t = 0.5 *402 * 1/50 or I2t = 0.5 *402 * 1/50 * 1/5