Fire and explosion proof instr. transformer with remote power supply - has supply outside danger zone and limiters independently protecting both units

摘要

The instrument transformer and power supply are connected together over a cable. The instrument transformer is located inside the danger zone and the power supply outside the same. The power supply has voltage and current limiters connected in series to the rectifier output and the instrument transformer has an input current limiter coupled over a voltage stabilising circuit to a voltage limiter. The two units are thus independently protected. Each limiter is doubled as an emergency protection.