Cable Insulation Voltage Level for Hazardous Area

Go for 1000V, then, if it's available locally. We are talking about armoured cables where the armour is earthed, aren't we? Provided the voltage in the cable is less than the cable's rated insulation voltage the normal cable insulation will be sufficient.

11kV cables can pass through hazardous areas.

For intrinsically safe circuits one can use uninsulated conductors, as the circuit design itself is intrinsically safe. Why one would want to use uninsulated conductors is another question.

Sorry, i was not clear in my question, i wonder what is the minimum insulation voltage level for the cable.

Would it not vary with the voltage applied
to the cable, which you neglect to state???

Why does it matter? Will the circuit voltage exceed the insulation rating? If so, then the wrong cable has been selected.

The hazardous area criterion is a "red herring".

I try to select a cable for 2 differents applications:

- 24V DC for 4-20ma SIGNALS

- 400VAC for power circuits.

If I Follow the french rules (I am french, but my projects are abroad: middle east, Asia, European countries and i have to follow ATEX or NFPA), I have to select 1000V insulation cable. I would prefer to use lowest insulation level, but I do not know the minimum levels.

For signal circuits check NFPA. 501.14

For 400V. stick with the 1KV. rating.
Any cost saving you might realise here is not worth the trouble.

For 24V DC use 300/500V rating.

For 400VAC use 1KV rating.