Channels, Fall 2016

Channels • 2016 • Volume 1 • Number 1 Page 103  Total Energy Consumption  Power Factor  Data Acquisition o Current Monitoring  Our system must have the monitoring capability of up to thirty circuits.  Each circuit can have a maximum of 20-A based on the fuses in the breaker box.  Device must be unobtrusive, meaning no wires should have to be disconnected from the breaker box to install the system.  Device must also fit comfortably within the circuit breaker box. o Voltage Monitoring  The device must have the complete voltage monitoring capability for one breaker box.  120-V supplies will be the only voltage monitored.  A step-down transformer must be used to capture the voltage waveform, creating a safe voltage level to measure.  The device must not leave 120-V circuitry exposed. o Waveforms  Both current and voltage signals must contain full-wave signals.  Accounts for dissymmetry of any signals.  Waveforms must be accurate to +/- 2%.  Circuit Protection o The PIC Microcontroller must be protected from any signal outside of its signal input range.  Both current and voltage signals must be clamped under 5.3-V.  Both current and voltage signals must be clamped above 0-V.  Filtering o Noise above 100-Hz must be filtered out of each signal. o Any RC delay constant must be consistent between voltage and current signals.  Analog to Digital Conversion o Uses a PIC Microcontroller to accurately convert thirty current signals and two voltage signals from analog to digital. o Sample at a rate high enough for an accurate conversion.  Printed Circuit Board o Must be under 60-in 2 . o Should be easily reproducible for scaling purposes. o Does not have to be all on one PCB. o Should be easily mountable into data acquisition unit.  Packing and Sending Data o Uses a Raspberry Pi to aggregate the digital data. o The Pi should also be responsible for performing the power and energy calculations so the PIC can focus on A/D conversion.