Microprocessor Differential Transformer Protection Relay

F87, F87N

Earthing leakage protection relay which is three phase with percentage differential and limited expedients to protection of two winding transformers feeded from double-winding or single source.

It measures the inlet currents and runs the vector group compensation of power transformer. Also, it actuates the current transformer transformation ratio without using additional current transformer.

• Differential protection with three phase percentage for double-winding transformers.
• Correction of automatic current transformer failure and transformer vector group.
• 2 pieces of differential current level
• Limited earth leakage level
• 2. and 5. Harmonic relatable qualification level
• Programmable percent- bias curve
• Oscilloscobic record
• Mod-bus communication protocol
• UL/CSA listing