Microchip Technology ARD00330 データシート
Calculation Engine and Register Description
© 2011 Microchip Technology Inc.
DS51933A-page 25
3.19
POWER_REACT
This is the value for reactive power. The goal is to get this value to equal X VAR/LSB.
This is done with the GAIN_POWER_REACT register. When displaying the power,
multiply the (decimal) value in this register by X to get the display value in Watts. This
register is overwritten every LINE_CYC line cycle (written only once if the calibration is
enabled).
This is done with the GAIN_POWER_REACT register. When displaying the power,
multiply the (decimal) value in this register by X to get the display value in Watts. This
register is overwritten every LINE_CYC line cycle (written only once if the calibration is
enabled).
3.20
PERIOD
This 32-bit register represents the total number of clock ticks that elapsed over the most
recent LINE_CYC line cycle. Each LSB represents 1.6 µs with a 40 MHz clock on the
microcontroller. This register is overwritten every LINE_CYC line cycle (written only
once if the calibration is enabled).
recent LINE_CYC line cycle. Each LSB represents 1.6 µs with a 40 MHz clock on the
microcontroller. This register is overwritten every LINE_CYC line cycle (written only
once if the calibration is enabled).
3.21
ENERGY_ACT
The design updates the Energy register using the CF Pulse blink output count. In this
method, the Energy registers increments every pulse by a value equal to
1/(METER_CONSTANT).
method, the Energy registers increments every pulse by a value equal to
1/(METER_CONSTANT).
ENERGY_W = ENEGRY_W + (1/METER_CONSTANT)
The gain calibration registers GAIN_NUMR_ENERGY_ACT and
GAIN_DENR_ENERGY_ACT hold good for this method also.
GAIN_DENR_ENERGY_ACT hold good for this method also.
3.22
ENERGY_APP
These two registers represent the total apparent energy accumulated so far.
Name
Bits
Cof
POWER_REACT
32
R
Name
Bits
Cof
PERIOD
32
R
Name
Bits
Cof
ENERGY_ACT
32
R
RAW_ENERGY_ACT
64
R
Name
Bits
Cof
ENERGY_APP
32
R
RAW_ENERGY_APP
64
R