HIGH-CURRENT ELECTRICAL POWER ENGINEERING APPARATUS AND INSTRUMENTS, NAMELY, TRANSFORMERS; TAP CHANGERS; ON-LOAD TAP CHANGERS; STEPPED TRANSFORMERS; STEP CHANGERS FOR TRANSFORMERS; POWER SWITCHES; AND DRIVERS AND ACTUATORS FOR TAP CHANGERS, ON-LOAD TAP CHANGERS, STEP CHANGERS AND POWER SWITCHES; LOW-CURRENT ELECTRICAL APPARATUS, NAMELY, CONTROLLERS, REGULATORS AND MONITORS FOR TRANSFORMERS; TAP CHANGERS; ON-LOAD TAP CHANGERS, STEPPED TRANSFORMERS; STEP CHANGERS FOR TRANSFORMERS, POWER SWITCHE...