Introduction
1 Definitions, Acronyms and Abbreviations
2 Overall Description
3 Metrology Interface Definition
- 3.1 Metrology Control Registers
  - 3.1.1 Metrology State Control
    Metrology State Control
  - 3.1.2 Metrology Feature Control Register
    Metrology Feature Control Register
  - 3.1.3 Harmonic Control Register
    Harmonic Control Register
  - 3.1.4 Meter Type Settings Register
    Meter Type Settings Register
  - 3.1.5 Number of Line Cycles for Integration Period
    Number of Line Cycles for Integration Period
  - 3.1.6 Max Number of Samples in an Integration Period
    Max Number of Samples in an Integration Period
  - 3.1.7 Pulse Control Register x (x = 0, 1, 2)
    Pulse Control Register x (x = 0, 1, 2)
  - 3.1.8 Meter Active Power Pulse Constant
    Meter Active Power Pulse Constant
  - 3.1.9 Meter Reactive Power Pulse Constant
    Meter Reactive Power Pulse Constant
  - 3.1.10 Meter Current Pulse Constant
    Meter Current Pulse Constant
  - 3.1.11 Meter Apparent Power Pulse Constant
    Meter Apparent Power Pulse Constant
  - 3.1.12 Creep Threshold for Active Energy
    Creep Threshold for Active Energy
  - 3.1.13 Creep Threshold for Quadergy
    Creep Threshold for Quadergy
  - 3.1.14 Creep Threshold of Phase Current
    Creep Threshold of Phase Current
  - 3.1.15 Creep Threshold for Apparent Energy
    Creep Threshold for Apparent Energy
  - 3.1.16 Power Offset Control Register
    Power Offset Control Register
  - 3.1.17 Active Power Offset Register
    Active Power Offset Register
  - 3.1.18 Reactive Power Offset Register
    Reactive Power Offset Register
  - 3.1.19 Apparent Power Offset Register
    Apparent Power Offset Register
  - 3.1.20 Voltage Swell Threshold
    Voltage Swell Threshold
  - 3.1.21 Voltage Sag Threshold
    Voltage Sag Threshold
  - 3.1.22 Current Conversion Factor
    Current Conversion Factor
  - 3.1.23 Voltage Conversion Factor
    Voltage Conversion Factor
  - 3.1.24 Current Channel Magnitude Calibration Constants
    Current Channel Magnitude Calibration Constants
  - 3.1.25 Voltage Channel Magnitude Calibration Constants
    Voltage Channel Magnitude Calibration Constants
  - 3.1.26 Per-Channel Phase Calibration Constants
    Per-Channel Phase Calibration Constants
  - 3.1.27 Waveform Capture Control Register
    Waveform Capture Control Register
  - 3.1.28 Capture Buffer Size
    Capture Buffer Size
  - 3.1.29 Waveform Capture Destination Buffer Address
    Waveform Capture Destination Buffer Address
  - 3.1.30 ATSENSE ADC Control Register 0
    ATSENSE ADC Control Register 0
  - 3.1.31 ATSENSE ADC Control Register 1
    ATSENSE ADC Control Register 1
  - 3.1.32 ATSENSE ADC Control Register 2
    ATSENSE ADC Control Register 2
  - 3.1.33 Per-Phase Active Power Offset Register
    Per-Phase Active Power Offset Register
  - 3.1.34 Per-Phase Reactive Power Offset Register
    Per-Phase Reactive Power Offset Register
- 3.2 Metrology Status Registers
- 3.3 Accumulated Output Quantities
- 3.4 Harmonic Analysis Output Quantities
- 3.5 Derived Output Quantities
4 Interface between Metrology and Application
5 Annex. Meter Forms
The service type determines what meter form is being implemented and how the Metrology DSP core interprets and processes the ADC values.
6 References
7 Revision History
Microchip Information

3.1.11 Meter Apparent Power Pulse Constant

S_K_t defines the meter test constant, which is the amount of apparent energy signified by one output pulse. S_K_t is in units of [VAh/pulse].

S_K_t is stored in uQ8.24 format.

In Europe and Asia, the pulse constant, MC, is used where MC is in units of [pulses/kVAh]. First, convert from units of MC to units of S_K_t (S_K_t = 1000/MC), then convert into uQ8.24 format by multiplying by 2²⁴.

For example, if MC = 800 pulses/kVAh, then S_K_t = 1000/800 = 1.25 VAh/pulse, and S_K_t = round[1.25 x 2²⁴] = 20971520 = 0x01400000

The frequency of pulse output generated depends on the quantity of energy measured and the defined pulse constants (P_K_t, Q_K_t, I_K_t and S_K_t). It is important to note that there is a limitation on the maximum frequency of pulse occurrence: the pulse period duration cannot exceed the sum of the pulse width plus an additional 500 microseconds.

For example, if the pulse width is set at 500 microseconds, the maximum pulse frequency that can be attained is 1 kHz. On the other hand, if the pulse width is reduced to 50 microseconds, the pulse frequency can increase to a maximum of 1.818 kHz.

Updates to S_K_t take effect at the next negative zero-crossing (narrow-band filtered version) of the present control phase voltage channel.

Name:	S_K_t
Property:	Read-Write


Bit	31	30	29	28	27	26	25	24
	S_K_t[31:24]
Access	R/W	R/W	R/W	R/W	R/W	R/W	R/W	R/W
Reset	0	0	0	0	0	0	0	0


Bit	23	22	21	20	19	18	17	16
	S_K_t[23:16]
Access	R/W	R/W	R/W	R/W	R/W	R/W	R/W	R/W
Reset	0	0	0	0	0	0	0	0


Bit	15	14	13	12	11	10	9	8
	S_K_t[15:8]
Access	R/W	R/W	R/W	R/W	R/W	R/W	R/W	R/W
Reset	0	0	0	0	0	0	0	0


Bit	7	6	5	4	3	2	1	0
	S_K_t[7:0]
Access	R/W	R/W	R/W	R/W	R/W	R/W	R/W	R/W
Reset	0	0	0	0	0	0	0	0

Bits 31:0 – S_K_t[31:0] (uQ8.24)