ADE9000 Technical Reference Manual
UG-1098
Rev. 0 | Page 17 of 86
ENERGY MEASUREMENTS OVERVIEW
AI_PCF
AV_PCF
PER PHASE
RMS AND
POWER
CALCULATION
AWATTHR
AFWATTHR
AVARHR
AFVARHR
AVAHR
AFVARHR
PER PHASE
ENERGY
ACCUMULATION
AWATT_ACC
AFWATT_ACC
AVAR_ACC
AFVAR_ACC
AVA_ACC
AFVA_ACC
CF1 PULSE OUTPUT
CF2 PULSE OUTPUT
CF3 PULSE OUTPUT
CF4 PULSE OUTPUT
ENERGY TO
FREQUENCY
AWATT
AFWATT
AVAR
AFVAR
AIRMS
AVRMS
AVA
AIFRMS
AVFRMS
AFVA
ADE9000
PER PHASE
POWER
ACCUMULATION
15523-
020
Figure 20. Per Phase Power and Energy Calculations from xI_PCF and xV_PCF Waveforms
Figure 20 shows how AI_PCF and AV_PCF are used to calculate
per phase rms and power calculations and how these are
accumulated into the AWATTHR and AWATT_ACC registers,
as well as the CFx pulse outputs.
Per Phase Energy Measurements Update Rate
Instantaneous power measurements, including as xWATT,
xVAR, xVA, and xFVAR, update at a rate of f
DSP
= 8 ksps.
These measurements are accumulated into power measurements
in the xWATT_ACC register, which updates at a user defined
interval of up to 1 sec, depending on the selection in the
PWR_TIME register.
Energy measurements update every f
DSP
= 8 ksps by default and
can store up to 106 sec of accumulation at full scale. Alternatively,
these registers can be set into a different accumulation mode
where they update after a user defined number of line cycles or
samples.
Power factor, ITHD, and VTHD measurements update every
4096/8 ksps = 1.024 sec.
RMS½ measurements update every ½ line cycle (10 ms at
50 Hz).
10 cycle rms/12 cycle rms measurements update every 10 cycles
on a 50 Hz network, or 12 cycles on a 60 Hz network. The
SELFREQ bit in the ACCMODE register defines which network
is being used.
Table 14. Watt Related Register Update Rates
Register
Name
Description
Update Rate
AWATT
Low-pass filtered total
active power on
Phase A
8 ksps
BWATT
Low-pass filtered total
active power on
Phase B
8 ksps
CWATT
Low-pass filtered total
active power on
Phase C
8 ksps
AWATT_
ACC
Accumulated total
active power on
Phase A
After the PWR_TIME 8 ksps
samples, from 250 µs to
1.024 sec
BWATT_
ACC
Accumulated total
active power on
Phase B
After the PWR_TIME 8 ksps
samples, from 250 µs to
1.024 sec
CWATT_
ACC
Accumulated total
active power on
Phase C
After the PWR_TIME 8 ksps
samples, from 250 µs to
1.024 sec
AWATTHR
Accumulated total
active energy on
Phase A
According to the settings in
EP_CFG and EP_TIME; holds
up to 106 sec of energy at
full scale.
BWATTHR
Accumulated total
active energy on
Phase B
According to the settings in
EP_CFG and EP_TIME; holds
up to 106 sec of energy at
full scale.
CWATTHR
Accumulated total
active energy on
Phase C
According to the settings in
EP_CFG and EP_TIME; holds
up to 106 sec of energy at
full scale.
APF
Phase A power factor
1
Every 1.024 sec
BPF
Phase B power factor
1
Every 1.024 sec
CPF
Phase C power factor
1
Every 1.024 sec
1
See the Power Factor section.