9 ELECTRICAL AND ELECTRIC TESTING AND MEASUREMENT DEVICES, NAMELY DEVICES FOR MEASURING VOLTAGE, CURRENT, RESISTANCE, AND ELECTRICAL TRANSMISSION, DEVICES FOR MEASURING CAPACITANCE AND INDUCTANCE, ROTATING FIELD INDICATORS; PHASE-SEQUENCE INDICATORS; ELECTRICAL AND ELECTRONIC APPARATUS, NAMELY POWER SUPPLIES, POTENTIOMETERS, FINE ADJUSTMENT LOCKS, ANALOGUE CONTROL INPUT, TRANSFORMERS AND ADJUSTABLE TRANSFORMERS; NETWORK APPARATUS, NAMELY STANDARD RAIL POWER UNITS, POWER SUPPLY PLUG-IN CARDS, NETWORK INSERTION BOARDS FOR ASSEMBLY FRAMES, ELECTRONIC LOADS, CURRENT SINKS; ADJUSTABLE APPARATUS FOR SUPPLYING A LOAD, NAMELY RESISTANCE DECADES, INDUCTANCE DECADES AND CAPACITANCE DECADES; NETWORK ANALYZERS, METERS FOR MEASURING HARMONIC OSCILLATIONS, ELECTRICAL PERFORMANCE ANALYZERS; OPTICAL-ELECTRONIC AND ELECTRO-OPTICAL MEASURING INSTRUMENTS, NAMELY OPTICAL POWER METERS AND OPTICAL LOSS TESTERS, STABILIZED LIGHT SOURCES, OPTICAL TIME DOMAIN REFLECTOMETERS