UG-572 Datasheet, PDF (17/20 Pages) Winchester Electronics Corporation – C JACK

EVAL-ADE7978EBZ User Guide
POWER QUALITY
The Power Quality windows provide access to all power quality
measurements performed inside the ADE7978: zero-crossing
detection, zero-crossing timeout and period measurement (see
Figure 28), neutral current mismatch (see Figure 29),
overvoltage and overcurrent detection (see Figure 30), peak
detection (see Figure 31), sag detection (see Figure 32), and
time intervals between phases (see Figure 33).
• At the top left, Active Measurement is used to select the
active window.
• Read Configuration reads all configuration registers used
inside the windows.
• Write Configuration writes all configuration registers with
the values introduced inside the windows.
• Wait For Interrupts manages the interrupts set in the
MASK1 register.
The procedure is as follows:
1. Set the interrupt to be monitored using the corresponding
switch placed in the window.
2. Set the other registers linked to the interrupt functionality.
3. Click the Write Configuration button to update the
ADE7978 registers.
4. Click the Wait For Interrupts button.
The program monitors the IRQ1 pin. When it is low, it cancels
the interrupt by writing to the STATUS1 register with the
corresponding interrupt flag set to 1. Then, it reads the ISUM,
PHSTATUS, IPEAK, VPEAK, ANGLE0, ANGLE1, and ANGLE2
registers and displays them. The Timeout for interrupts boxes
are used to set the amount of time in milliseconds that the part
waits for a zero crossing. Time MCU waits until cancelling
interrupts sets the amount of time the Blackfin processor of
the SDP-B board waits before resetting an interrupt.
UG-572
Figure 29. Power Quality Neutral Current Mismatch Window
Figure 30. Power Quality Overvoltage and Overcurrent
Measurements
Figure 28. Power Quality Zero-Crossing Measurements
Rev. 0 | Page 17 of 20
Figure 31. Power Quality Peak Detection