Electrical components, namely, switches[, inverters, ]plugs, sockets[, electromagnets], transformers, shunts, [thermostats] and power supplies; electronic sensors sensing optical signals by means of diodes,[ transistors; barcode reader equipment, namely, readers and scanners;] receivers for electro magnetic signals; resistor ladders for AC and DC voltage signals; transmitters generating optical, electrical or electro magnetic signals; signal converters, surveillance and control units for calc...