Analog Devices ADSST-SALEM-3T User Manual

Page of 24
 
 
 
Powerful Energy Meter Chipset
 
ADSST-SALEM-3T
 
 
Rev. 0  
Information furnished by Analog Devices is believed to be accurate and reliable. 
However, no responsibility is assumed by Analog Devices for its use, nor for any 
infringements of patents or other rights of third parties that may result from its use. 
Specifications subject to change without notice. No license is granted by implication 
or otherwise under any patent or patent rights of Analog Devices. Trademarks and 
registered trademarks are the property of their respective owners.
 
 
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. 
Tel: 781.329.4700
 
Fax: 781.326.8703
© 2004 Analog Devices, Inc. All rights reserved. 
FEATURES 
High accuracy 
Supports IEC 60687/61036 and ANSI C12.1/12.20 
Suitable for class0.5 and class0.2 meter 
Full four quadrant measurement of parameters 
SPI® compatible serial interface  
Pulse output with programmable pulse constant as 
pulses/kWh or Wh/pulse 
Programmable duty cycle for pulse output 
Embedded calibration routines for gain and dc offset  
Software based phase and nonlinearity compensation for 
current transformers 
15 kHz sampling frequency 
UART mode enables a PC to directly access all computed 
parameters 
Flags to indicate tamper conditions  
Single 3.0 V supply 
Developer’s kit to accelerate design process (See  
   Ordering Guide for separate ordering number.) 
GENERAL DESCRIPTION 
 
The ADSST-SALEM-3T energy meter chipset consists of an 
efficient ADSST-218x digital signal processor (DSP), a fast and 
accurate 6-channel, 16-bit ADSST-73360LAR sigma-delta ana-
log-to-digital converter (ADC), and metering software. Two 
chipset versions are available to support differing ranges of  
operating temperature: The ADSST-EM-3040 chipset is rated at 
0°C to 70°C for commercial applications, while the ADSST-EM-
3041 chipset operates at –25°C to +85°C for industrial use.  
 
µC
DSP
BUTTONS
CT
SMPS
LCD DISPLAY
RTC
FLASH
SPI BUS
RS-232
OPTO
CT
CT
ADC
ADSST-EM-3040
RESISTOR
BLOCK
BOOT
FLASH
03738- 0- 001
 
Figure 1. Block Diagram of a Functional Meter 
The ADC and DSP are interfaced to simultaneously acquire 
voltage and current samples on all three phases and to perform 
mathematically intensive computations to calculate various 
instantaneous parameters and perform harmonic analysis. The  
chipset can be interfaced to any general-purpose microproces-
sor to develop state of the art tri-vector or polyphase energy 
metering solutions with a wide range of basic currents from 1 A 
to 30 A. By incorporating a comprehensive data set of parame-
ters, including instantaneous measurements, accumulated 
parameters, and harmonic analysis data, the ADSST-SALEM-3T 
chipset meets high end energy metering requirements. The abil-
ity to easily configure the chipset for various parameters makes 
it a very flexible solution. 
The phase and nonlinearity compensation for current 
transformers is done in software (patent pending) without 
having to use any passive components in the circuit for 
compensation, thus minimizing variations in accuracy with 
temperature and time. 
The ADSST-SALEM-3T measures and computes a large num-
ber of parameters essential for high end metering. 
Table 1. 
Parameter Each 
Phase 
Total 
RMS Voltage 
 
 
RMS Current 
 
 
Active Power 
 
 
Apparent Power 
 
 
Inductive Reactive Power 
 
 
Capacitive Reactive Power 
 
 
Power Factor 
 
 
Frequency 
 
 
Positive Active Energy 
 
 
Negative Active Energy 
 
 
Apparent Energy 
 
 
Positive Inductive Reactive Energy 
 
 
Negative Inductive Reactive Energy 
 
 
Positive Capacitive Reactive Energy 
 
 
Negative Capacitive Reactive Energy 
 
 
Voltage Magnitude and Phase for All 
Odd Harmonics up to 21
st
 Order 
 
 
Current Magnitude and Phase for All 
Odd Harmonics up to 21
st
 Order 
 
 
 
The ADSST-SALEM-3T offers some excellent features that 
make the final meter cost-effective and easy to manufacture.