Datasheet
90E32AS ENHANCED POLY-PHASE HIGH-PERFORMANCE WIDE-SPAN ENERGY METERING IC
Function Description 17 April 2, 2013
3.5.4 STARTUP AND NO-LOAD POWER
There are startup power threshold registers (e.g. PStartTh(35H)).
Refer to 5.4 Configuration and Calibration Registers. The power thresh-
old registers are defined for all-phase-sum active, reactive and apparent
power. The 90E32AS starts metering when the corresponding all-phase-
sum power is greater than the startup threshold. When the power value
is lower than the startup threshold, energy is not accumulated and it is
assumed as in no-load status. Refer to Figure-6.
There are also no-load Current Threshold registers for Active, Reac-
tive and Apparent energy metering participation for each of the 3
phases. If |P|+|Q| is lower than the corresponding power threshold, that
particular phase will not be accumulated. Refer to the PStartTh register
and other threshold registers.
There are also no-load status bits (the TPnoload/TQnoload bits
(b14~15, Fundamental / Harmonic Energy Register)) defined to reflect
the no-load status. The 90E32AS does not output any pulse in no-load
status. The power-on state is of no-load status.
Figure-6 Active Power Startup/Noload Processing
Figure-7 Fundamental Active Power Startup/Noload Processing
Phase Active
Energy Metering
0
1
0
Total Active
Energy Metering
ABS >
PStartTh?
0
1
0
Total Active Power
+
ENA
ABS or Arithmatic
ENB ENC
0
1
Phase Active
Power from DSP
0
Phase |P| + |Q| >
PPhaseTh?
0
1
Phase Active
Power from DSP
0
Phase |P| + |Q| >
PPhaseTh?
0
1
Phase Active
Power from DSP
0
Phase |P| + |Q| >
PPhaseTh?
C
A
B
Active Power
Startup/Noload handling
NoLoad Status
Phase Active
Fund Energy
Metering
0
1
0
Total Active Fund
Energy Metering
ABS >
PStartTh?
0
1
0
Total Active Fund
Power
+
ENA
ABS or Arithmatic
ENB ENC
0
1
Phase Active
Power from DSP
0
Phase |P| + |Q| >
PPhaseTh?
0
1
Phase Active
Power from DSP
0
Phase |P| + |Q| >
PPhaseTh?
0
1
Phase Active
Fundamental
Power from DSP
0
Phase |P| + |Q| >
PPhaseTh?
C
A
B
Active Power
startup/Noload handling
NoLoad Status
Total Active Power