Amtech 3 phase tx load

[Richard3009]

Just trying to work out a cable and fuse size for a 3kva 415/240v transformer with a 2kW load on it, using Amtech single cable, there are no settings for showing a transformer on the load side, is it possible to calc a transformer load on Amtech.

If I use a motor as the load it chooses fuses very close to the load rating, but I'm sure the transformer inrush will rupture them. I can uprate the fuses but if I do that what's the point of using Amtech in the first place.

 

[Pete999]

Do a calc for the TX load and then do a calc for the secondary load

 

[Richard3009]

Do a calc for the TX load and then do a calc for the secondary load

how do you work out the transformer "load" with nothing on it, there is nothing in Amtech to use

 

[Pete999]

Well it's bound to have a kva rating or should have

 

[Richard3009]

Should the primary fuses be inrush rated for 3kva + 10% and the secondary fuses rated for the load

 

[Pete999]

What do you think?

 

[Richard3009]

What do you think?

I don't know, are we calculating transformer inrush plus the load on the primary? and just the load on the secondary can we rely on just the primary fuses to protect the whole circuit?

 

[Pete999]

If the TX has bee sized correctly, then size the protection on the secondary to suit the designed load.

 

[Besoeker]

Just trying to work out a cable and fuse size for a 3kva 415/240v transformer with a 2kW load on it, using Amtech single cable, there are no settings for showing a transformer on the load side, is it possible to calc a transformer load on Amtech.

If I use a motor as the load it chooses fuses very close to the load rating, but I'm sure the transformer inrush will rupture them. I can uprate the fuses but if I do that what's the point of using Amtech in the first place.

Is it 240V single phase?

 

[Richard3009]

Is it 240V single phase?

supply to the transformer is 2 wire 415v, output is 240v single phase yes, do you calc the cable based on a the kva rating of the transformer, could you just use a 3 phase motor to rate it on amtech