protection for cables in parallel

[Pafi]

Hello!
I have a load supplied with 2 cables in parallel per phase and I had to use 1000A/ 690V fuses in order to protect the cables for short circuit. These fuses are hard to find - not on stock, anyway - and size is 4a. Can I use instead one fuse for each of the 2 identical cables in parallel(let's say grosso modo 500A fuse for each cable)? Is there any requirement why I shouldn't do that?
Thanks!
Pafi

 

[qman5]

It will come down to individual element protection. Let's say, for a rare scenario, one cable of the phase is shorted from electrical or mechanical damage. If this happens, your healthy phase will assume full load current. If you do not have protection elements available for the indication of a faulted cable, the cable will assume the full rated current.

Can you guarantee that this scenario won't happen? If not, you need individual phase protection.