EVAL-ADE7816EBZ AD [Analog Devices], EVAL-ADE7816EBZ Datasheet - Page 28

• Manufacturer Part Number: EVAL-ADE7816EBZ
• Description: Six Current Channels, One Voltage Channel
• Manufacturer: AD [Analog Devices]

ADE7816
As shown in Figure 34, the OV bit (Bit 18) in the STATUS1 register
(Address 0xE503) is set to 1 if the
condition. The overcurrent detection feature works in a similar
manner; however, a group of current channels (A, B, C or D, E, F)
must be selected by Bit 14 (CHANNEL_SEL) of the COMPMODE
register, Address 0xE60E (see the Selecting a Current Channel
Group section). When switching between current channel groups,
no additional settling time is required and the feature continues to
monitor at an 8 kHz rate. If an overcurrent condition is detected on
any of the selected current channels, the OI bit (Bit 17) of the
STATUS1 register is set to 1. To determine the current channel(s)
causing the overcurrent event, the OICHANNELx bits (Bit 3, Bit 4,
and Bit 5) of the CHSTATUS register are used.
Setting the OVLVL and OILVL Registers
The content of the overvoltage (OVLVL) and overcurrent (OILVL),
24-bit, unsigned registers is compared to the absolute value of
the voltage and current channels. The maximum value of these
registers is 5,928,256 (0x5A7540) with full scale inputs. When
either the OVLVL or OILVL register is equal to this value, the
overvoltage or overcurrent conditions are never detected.
Writing 0x0 to these registers signifies that the overvoltage or
overcurrent conditions are continuously detected, and the
corresponding interrupts are permanently triggered.
Overvoltage and Overcurrent Interrupts
Two interrupts are associated with the overvoltage and overcurrent
features. The first interrupt is associated with the overvoltage
feature; it is enabled by setting the OV bit (Bit 18) of the MASK1
register (Address 0xE50B). When this bit is set, an overvoltage
condition causes the external IRQ1 pin to be pulled low. A second
interrupt is associated with the overcurrent detection feature.
This interrupt is enabled by setting the OI bit (Bit 17) of the
MASK1 register. When this bit is set, an overcurrent condition
on any of the selected current channels causes the external
IRQ1 pin to be pulled low.
INDICATION OF POWER DIRECTION
The
power measurements. Sign indication allows positive and negative
energy to be identified and billed separately, if required. It also
helps detect a miswiring condition. This feature is available on
three channels at a time. A group of current channels (A, B, C
or D, E, F) must be selected by Bit 14 (CHANNEL_SEL) of the
COMPMODE register at Address 0xE60E (see the Selecting a
Current Channel Group section).
The three-sign indication bits that indicate the polarity of the
active power are Bit 0 (W1SIGN), Bit 1 (W2SIGN), and Bit 2
(W3SIGN) of the CHSIGN register (Address 0xE617). W1SIGN
indicates the direction of power on the A or D current channel,
W2SIGN indicates the direction of power on the B or E current
channel, and W3SIGN indicates the direction of power on the C
or F current channel. An additional three bits, VAR1SIGN (Bit 4),
VAR2SIGN (Bit 5), and VAR3SIGN (Bit 6), also in the CHSIGN
register, provide the direction of the reactive power. All of these
ADE7816
includes sign indication on the active and reactive
ADE7816
detects an overvoltage
Rev. 0 | Page 28 of 48
bits are unlatched and read only. A low reading (0) on any of
these bits indicates that the corresponding power reading is
positive; a high reading (1) indicates that the corresponding
power reading is negative.
In addition to the sign indication bits, the
reverse power status bits and associated interrupts. The status bits
are located in the STATUS0 register (Address 0xE502). The reverse
power bits are set to 1 when the sign of the power changes. Bit 6
(REVAP1) monitors the A or D current channel, Bit 7 (REVAP2)
monitors the B or E channel, and Bit 8 (REVAP3) monitors the
C or F current channel. Similarly, Bit 10 (REVRP1), Bit 11
(REVRP2), and Bit 12 (REVRP3) monitor the reactive power.
Both positive-to-negative and negative-to-positive changes result
in the corresponding status bit being set. Each status bit has a cor-
responding interrupt enable bit that is located in the MASK0
register (Address 0xE50A). If the corresponding MASK0 bit is set,
a change in active energy power direction causes the external IRQ0
pin to be pulled low (see the Interrupts section for more details).
ANGLE MEASUREMENTS
The
and voltage inputs. It can also be configured to measure the time
between the six current channels. The negative-to-positive
transitions identified by the zero-crossing detection circuit are
used as a start and stop for the measurement (see Figure 35).
There are three angle registers that store the results of the time
delay. A group of current channels (A, B, C or D, E, F) must be
selected by Bit 14 (CHANNEL_SEL) of the COMPMODE
register (see the Selecting a Current Channel Group section).
When Bits[10:9] (ANGLESEL) of the COMPMODE register are
set to 00b (default), the time delays between the current channels
and the voltage channel are measured. The ANGLE0 register
(Address 0xE601) stores the delay between the voltage and the
A or D current channel. The ANGLE1 register (Address 0xE602)
stores the delay between the voltage and the B or E current
channel. The ANGLE2 register (Address 0xE603) stores the delay
between the voltage and the C or F current channel. The time delay
between the current and voltage inputs can be used to characterize
how balanced the load is. The delays between phase voltages and
currents can be used to compute the power factor, as shown
in Equation 16.
where f
ADE7816
cos
LINE

x
is 50 Hz or 60 Hz.

cos
can measure the time delay between the current
Figure 35. Voltage-to-Current Time Delay
VOLTAGE
ANGLE

 

ANGLEx

CHANNEL X
360
CURRENT
256
o

kHz
f
LINE
ADE7816

 

Data Sheet
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