The JDZX11-15 \20 voltage transformers is indoor, single-phase, epoxy resin cast, residual winding-equipped potential transformers (PT), used in sets of three for three-phase systems. They are suitable for 15/20 kV indoor switchgear (such as medium-mounted or ring main units) and are used for voltage measurement, monitoring, relay protection, and zero-sequence grounding protection via open delta connection.
Main Parameters:
• Rated frequency: 50/60 Hz
• Rated voltage ratio (three-phase star connection):
◦ JDZX11-15: 15/√3 : 0.1/√3 : 0.1/3 kV
◦ JDZX11-20: 20/√3 : 0.1/√3 : 0.1/3 kV
• Insulation level:
◦ 15 kV: 18/55/105 kV
◦ 20 kV: 24/65/125 kV
• Accuracy class / Output (VA, cosφ=0.8):
◦ Class 0.2: 30 VA; Class 0.5: 80 VA; Class 1: 200 VA; Protection class: 6P
◦ Maximum output: 400–600 VA
• Construction: Indoor dry-type, vacuum epoxy casting, fully insulated and sealed
