71M6521DH MAXIM [Maxim Integrated Products], 71M6521DH Datasheet - Page 48
71M6521DH
Manufacturer Part Number
71M6521DH
Description
Energy Meter ICs
Manufacturer
MAXIM [Maxim Integrated Products]
Datasheet
1.71M6521DH.pdf
(107 pages)
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
71M6521DH-IGT
Manufacturer:
TERIDIAN
Quantity:
3 000
- Current page: 48 of 107
- Download datasheet (3Mb)
FUNCTIONAL DESCRIPTION
The energy delivered by a power source into a load can be expressed as:
Assuming phase angles are constant, the following formulae apply:
For a practical meter, not only voltage and current amplitudes, but also phase angles and harmonic content may
change constantly. Thus, simple RMS measurements are inherently inaccurate. A modern solid-state electricity meter
IC such as the Teridian 71M6521DE/DH/FE functions by emulating the integral operation above, i.e. it processes
current and voltage samples through an ADC at a constant frequency. As long as the ADC resolution is high enough
and the sample frequency is beyond the harmonic range of interest, the current and voltage samples, multiplied with
the time period of sampling will yield an accurate quantity for the momentary energy. Summing up the momentary
energy quantities over time will result in accumulated energy.
Figure 15 shows the shapes of V(t), I(t), the momentary power and the accumulated power, resulting from 50
samples of the voltage and current signals over a period of 20ms. The application of 240VAC and 100A results in an
accumulation of 480Ws (= 0.133Wh) over the 20ms period, as indicated by the Accumulated Power curve.
The described sampling method works reliably, even in the presence of dynamic phase shift and harmonic distortion.
Page: 48 of 107
P = Real Energy [Wh] = V * A * cos φ* t
Q = Reactive Energy [VARh] = V * A * sin φ * t
S = Apparent Energy [VAh] =
-100
-200
-300
-400
-500
500
400
300
200
100
0
0
Figure 15: Voltage. Current, Momentary and Accumulated Energy
Current [A]
Voltage [V]
Energy per Interval [Ws]
Accumulated Energy [Ws]
5
Theory of Operation
P +
2
E
Q
=
2
∫
0
t
V
10
) (
t
I
) (
t
dt
15
71M6521DE/DH/FE Data Sheet
20
Rev 2
Related parts for 71M6521DH
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
LCC/M°/CIRCUITI INTEGRATI MAXIM
Manufacturer:
Maxim Integrated Products
Datasheet:
Part Number:
Description:
KIT/E/MAXIM ANALOG ESSENTIALS # COLLECTION OF PLUG-IN EVALUATION MODULES
Manufacturer:
Maxim Integrated Products
Part Number:
Description:
Single +5V, fully integrated, 1.25Gbps laser diode driver.
Manufacturer:
Maxim Integrated Products
Datasheet:
Part Number:
Description:
Single +5V, fully integrated, 155Mbps laser diode driver.
Manufacturer:
Maxim Integrated Products
Datasheet:
Part Number:
Description:
VRD11/VRD10, K8 Rev F 2/3/4-Phase PWM Controllers with Integrated Dual MOSFET Drivers
Manufacturer:
Maxim Integrated Products
Datasheet:
Part Number:
Description:
Highly Integrated Level 2 SMBus Battery Chargers
Manufacturer:
Maxim Integrated Products
Datasheet:
Part Number:
Description:
Current Monitor and Accumulator with Integrated Sense Resistor; ; Temperature Range: -40°C to +85°C
Manufacturer:
Maxim Integrated Products
Part Number:
Description:
TSSOP 14/A°/RS-485 Transceivers with Integrated 100O/120O Termination Resis
Manufacturer:
Maxim Integrated Products
Part Number:
Description:
TSSOP 14/A°/RS-485 Transceivers with Integrated 100O/120O Termination Resis
Manufacturer:
Maxim Integrated Products
Part Number:
Description:
QFN 16/A°/AC-DC and DC-DC Peak-Current-Mode Converters with Integrated Step
Manufacturer:
Maxim Integrated Products
Part Number:
Description:
TDFN/A/65V, 1A, 600KHZ, SYNCHRONOUS STEP-DOWN REGULATOR WITH INTEGRATED SWI
Manufacturer:
Maxim Integrated Products
Part Number:
Description:
Integrated Temperature Controller f
Manufacturer:
Maxim Integrated Products
Part Number:
Description:
SOT23-6/I°/45MHz to 650MHz, Integrated IF VCOs with Differential Output
Manufacturer:
Maxim Integrated Products
Part Number:
Description:
SOT23-6/I°/45MHz to 650MHz, Integrated IF VCOs with Differential Output
Manufacturer:
Maxim Integrated Products
Part Number:
Description:
EVALUATION KIT/2.4GHZ TO 2.5GHZ 802.11G/B RF TRANSCEIVER WITH INTEGRATED PA
Manufacturer:
Maxim Integrated Products