EVAL-ADE7878EBZ Analog Devices Inc, EVAL-ADE7878EBZ Datasheet - Page 13

• Manufacturer Part Number: EVAL-ADE7878EBZ
• Description: Energy Meter Eval. Board
• Manufacturer: Analog Devices Inc

Specifications of EVAL-ADE7878EBZ

• Silicon Manufacturer: Analog Devices
• Application Sub Type: Energy Meter
• Kit Application Type: Data Converter
• Silicon Core Number: ADE7878
• Features: External Transducers, LED Indicators, Logic Outputs
• Kit Contents: Board
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: Q4472972; Q4684026; Q5015773

Preliminary Technical Data
EVAL-ADE7878EB
Figure 24. Time Intervals Between Phases panel
Figure 21. Neutral Current Mismatch panel
Waveform Sampling
This panel (see Figure 25) uses HSDC port to acquire data from
the ADE7878 and visualize it. It can be accessed only if the
2
communication between ADE7878 and LPC2368 is I
C. See
Activating Serial Communication ADE7878 − LPC2368 section
2
for details on how to set I
C communication on the ADE7878
evaluation board.
The HSDC transmits data to LPC2368 at 4MHz because this is
the maximum speed the slave SPI of LPC2368 can receive data.
The panel contains some switches that must be set before
acquiring data:
-One switch chooses what quantities are visualized: phase
currents and voltages or phase powers. For every set of
quantities, only two can be acquired at a time. This choice is
done using the buttons “Select Waveform1” and “Select
Waveform2”.
Figure 22. Overvoltage & Overcurrent management panel
-A second switch allows for acquired data to be stored in files
for further utilization.
-The acquisition time should also be set before an acquisition is
ordered. By default, this time is 150msec. It is limited for phase
currents and voltages for up to 1sec, but for phase powers is
unlimited. This difference appears because the LPC2368 must
execute in real time three tasks using the ping pong buffer
method: continuously receiving data from HSDC, storing it into
its USB memory, sending it to the PC. More time it takes the
HSDC to transmit data, more time LPC2368 has to transmit
data to the PC. As transmitting 6 phase currents and voltages at
4MHz takes 103.25μsec, less than 125 μsec, but transmitting 9
phase powers takes 133.25μsec, more than 125 μsec, the first
quantities are transmitted by HSDC at 8KHz update rate and
the second at 4KHz rate. This means the phase currents and
voltages can be acquired only for up to 1sec before the LPC2368
goes out of bandwidth and the powers can be acquired for an
Figure 23. Peak management panel
unlimited time.
Rev. PrB | Page 13 of 30