Single phase power analyser. This is an effort to create a simple and affordable power analyser for single phase opearation. * Measurement circuit: Voltage: transformer -> resistor divider Resistor network is used to divide the transformer output to about 3 Vpp for normal conditions (240Vrms) allowing slight overvoltage. Current: ACS758-050B -> OP284 gain stage (for resolution enchancement) As the noise of the ACS758 will limit the resolution to under 12 bits, there is no need to use separate AD inputs, just single gain stage pumping full scale to +-20 amps or so (~14amps RMS). * Compilation: This code will compile with GCC ARM embedded suite https://launchpad.net/gcc-arm-embedded Screen 20x4 HD: 01234567890123456789 1 000.0 V 00.000 A ; voltage, current 2 0000.0 W 0000.0 VA ; real power, apparent power 3 PF=x.xx ; powerfactor 4 000.00Hz ; mains freq. BOM: STM32F103 minimum system 5 USD 20x4 display 4 USD ACS758-050B 4 USD 2 x 8V transformer 10 USD Cs,Rs,7805,bridge etc 10 USD PCB 5 USD Total 38 USD