71M6515H-IGT/F Maxim Integrated Products, 71M6515H-IGT/F Datasheet - Page 26

• Manufacturer Part Number: 71M6515H-IGT/F
• Description: IC ENERGY METER AFE 3PH 64-LQFP
• Manufacturer: Maxim Integrated Products

Specifications of 71M6515H-IGT/F

• Mounting Style: SMD/SMT
• Package / Case: LQFP-64
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Calibration with Three Measurements
The simplest calibration method is to make three measurements. Typically, a voltage measurement and two Watt-hour (Wh)
measurements are made.
If the voltage measurement has the error E
with φ
zero when the meter is accurate and negative when the meter runs slow. The fundamental frequency is f
where f
PHADJ_A = 0.
From the voltage measurement, we determine that
1.
We use the other two measurements to determine φ
2.
2a.
3.
3a.
Combining 2a and 3a:
4.
5.
6.
and from 2a:
7.
Now that we know the A
Page: 26 of 60
CAL
L
_
φ
= 0 and E
E
E
E
E
tan(
A
A
A
S
V
S
0
XV
60
60
XI
XV
60
is the sample frequency (2520.62Hz). Set all calibration factors to nominal: CAL_IA = 16384, CAL_VA = 16384,
NEW
=
=
φ
=
A
=
=
=
=
A Maxim Integrated Products Brand
=
tan
S
XI
IV
A
IV
E
)
A
A
E
=
XV
=
XV
=
XV
0
−
V
A
60
1
E
CAL
A
+

 

(
cos(
A
XV
cos(
A
+
0
E
is measured with φ
E
XV
(
(
XI
A
XI
IV
E
+
1
0
0
E
IV
A
E
XV
0
1
[
φ
A
cos(
+
+
φ
0
cos(
E
_
XI
XV
60
cos(
+
S
S
1
XI
) 1
cos(
+
60
V
, A
)
) 1
)
cos(
−
) 1
cos(
tan(
φ
−
60
XI
tan(
) 0
E
S
, and φ
tan(
60
E
0
0
)
)
0
60
60
+
cos(
−
)
60
cos(
60
)
φ
A
−
)
S
S
XV
φ

 

φ
)
)
60
errors, we calculate the new calibration voltage gain coefficient from the previous ones:
L
S
tan(
S
A
= 60. These values should be simple ratios—not percentage values. They should be
−
© 2005−2011 Teridian Semiconductor Corporation
)
)
)
1
XI
+
−
=
V
φ
sin(
tan(
1
S
and the two Wh measurements have errors E
A
=
)
XV
60
A
60
XV
S
A
)
)
sin(
and A
XI
sin(
A
cos(
XI
φ
φ
cos(
S
XI
S
)
φ
.
)
]
cos(
S
−
−
)
60
1
1
−
60
1
−
φ
)
S
)
−
1
Energy Meter IC
0
and E
DATA SHEET
71M6515H
60
, where E
0
. T is equal to 1/f
0
is measured
JULY 2011
1.6
S
,