SA9603C Datasheet, PDF (11/18 Pages) Sames – SINGLE PHASE BIDIRECTIONAL POWER/ENERGY METERING IC WITH SERIAL INTERFACE

SA9603C
8. Calibration
For calibration of the SA9603C, the following procedure is recommended:
a. Establish the calibration factor for active energy (Ka) at power factor (PF)
close to 1.
Active (Measured) = register_value (Active) * Ka.
1
b. The factor for reactive (Kr) is typically Ka * PI/2.
For higher accuracy of Kr, establish Kr at PF close to 0.
Reactive (Measured) = register_value (Reactive) * Kr
2
c. At PF close to 1, establish error for reactive (Er)
Er = (Reactive (Measured) - Reactive (True)) / Active (Measured)
3
Reactive (Corrected) = Reactive (Measured) - Er * Active (Measured) 3b
Measurement
Having determined the scaling factors (Ka & Kr) and error correction constant (Er)
the measurement cycle consists of the following steps:
Step 1 Read active register
∨
Step 2 Calculate Active (Measured) as per 1
Step 3
Step 4
∨
Read reactive register
∨
Calculate Reactive (Measured) as per 2
∨
Step 5 Perform error correction
Calculate Reactive (Corrected) as per 3b
⇒ Active energy
⇒ Reactive energy
The above five steps must be performed for each measurement cycle.
sames
11/18