POWER TRANSFORMER VACUUM CIRCUIT BREAKER LOOPED NETWORK CABINET DRY TYPE TRANSFORMER RECTIFIER TRANSFORMER DRY TYPE IRON-CORE REACTOR INDEPENDENT TYPE ELECTRIC CURRENT MUTUAL INDUCTOR DRY TYPE AIR REACTOR MUTUAL INDUCTOR MIDDLE-SET SWITCHGEAR AUTOMATIC-TUNING ARC-EXTINCTION COIL EARTHING SYSTEM IRON CORE REACTOR HOLLOW REACTOR ELECTRIFIED CIRCUIT TRANSFORMER COMBINED TRANSFORMER POWER DISTRIBUTION TRANSFORMER ELECTRIC STOVE TRANSFORMER ON-LOAD TAP-CHANGING TRANSFORMER TRANSFORMER WITH PROTECTIVE CASE STANDARD ENCLOSED BUSBAR LOW VOLTAGE STANDARD HORIZONTAL SIDE OUTLET LINE LOW VOLTAGE STANDARD VERTICAL SIDE OUTLET LINE DYNAMOMETER LOAD CURRENT MONITOR NULL SEQUENCE IMPEDANCE TEMPERATURE CONTROL SYSTEM