Signal Cables

Most possibly you will burn your cirquits. No level indicator can handle 1KV (that 1KV cable always carrys as you know)

1. Is there will be a problem if i use 1.5mm2 0.6/1 kV CVV cables as a signal cable rather than using a 24V DC signal cable? The cable will go to instruments (Flowmeter, level indicators, etc.) and it will use as a pulse and analog signal (4-20mA).

Short answer, possibly due to the fact the CVV cable has no screen.

2. What would be the dilemna if i will use power cable or control cable instead a right signal cable for the equipment?

http://en.wikipedia.org/wiki/Electromagnetic_interference

3. What normally brand was use

Depends on site standards. Consult the site standards, tender information, etc.