MAXQ3180 Maxim, MAXQ3180 Datasheet - Page 51

• Manufacturer Part Number: MAXQ3180
• Description: The MAXQ3180 is a dedicated electricity measurement front-end that collects and calculates polyphase voltage, current, power, energy, and many other metering and power-quality parameters of a polyphase load
• Manufacturer: Maxim

* These registers represent the algebraic sum of the positive and reverse energy in the two “raw” registers noted. Thus, the energy
accumulated in these virtual registers represents the net energy.
To avoid significant conversion loss, ENR_LSB should be chosen such that ENR_CC is > 1000. Calculate the value
of ENR_CC according to the following formula:
The virtual registers are calculated values derived from one or more real registers. They are calculated at the time
they are requested, and thus could involve additional time to return a value. Most virtual registers are 8 bytes in
length and are delivered least significant byte first.
This signed register contains the real instantaneous power delivered into phase A/B/C or total. Power is calculated
from the instantaneous energy measurement according to the following equation:
The register is 8 bytes long, but the most significant 2 bytes are not used. See the PWR_CC register description for
more details.
Note that the sign bit is bit 47 for all 8-byte signed virtual registers.
Reactive energy, phase C, positive direction, fundamental only
Reactive energy, phase C, reverse direction, fundamental only
Reactive energy, total, fundamental only
Apparent energy, phase A, fundamental only
Apparent energy, phase B, fundamental only
Apparent energy, phase C, fundamental only
Apparent energy, total, fundamental only
Real Power, Phase X = A/B/C/T (PWRP.X) (A: 0x801, B: 0x802, C: 0x804, T: 0x807)
Low-Power, Multifunction, Polyphase AFE
______________________________________________________________________________________
Byte 7 (MSByte unused)
Byte 5
Byte 3
Byte 1
Energy Units Conversion Coefficient (ENR_CC) (0x01A) (continued)
DESCRIPTION
PWRP X
ENR CC
_
.
=
=
X ACT
.
2
I
FS
16
×
×
×
V
ENR LSB
PWR CC
FS
NS
×
_
t
_
FR
× 2
16
C.ERFNEG
Byte 6 (unused)
C.ERFPOS
Byte 0 (LSByte)
C.ESF
A.ESF
B.ESF
RAW
—
—
Byte 4
Byte 2
Virtual Registers
ENRQF.C*
VIRTUAL
ENRQF.T
ENRSF.A
ENRSF.B
ENRSF.C
ENRSF.T
Power
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