INTRODUCTION

This Application Note describes the functionality of the

SA2007M and the SA2007P metering integrated circuits using

the PM2007M/PPE evaluation module. The SA2007 family is a

low cost solution specifically designed to meet the needs of

markets that require both live and neutral energy

measurement to detect any meter tampering. Using the

SA2007 family the meter manufacturer is able to build a meter

that measures the energy consumption, even during a tamper

condition, and record it to a mechanical counter.

This application note will focus on the practical use of the

SA2007 family. More detailed information specific to the

SA2007M or SA2007P can be found in the applicable

datasheet.

The SA2007 family is characterized by its ability to measure

live and neutral power consumption simultaneously. A

correctly installed meter should measure equal amounts of

power consumption in the live and neutral phases. During

meter tampering the two measurements are no longer equal.

The SA2007 will use the larger of the two currents for the

energy measurement. Differences of more than 12% between

the live and neutral power measurements are indicated on the

SA2007’s ELT output which can drive a LED directly. However

the SA2007 will use the larger of the two currents even if the

difference is less than a percent.

The SA2007 is designed to drive mechanical counters directly.

The module is fitted with an impulse type counter that

increments with a single 71ms pulse. The SA2007 can also

drive low cost mechanical counters (stepper motors) that use

two consecutive pulses with opposing voltages to advance the

counter one position. The SA2007 outputs these two opposing

pulses in close succession, minimizing the chance of the

stepper motor being in the wrong phase after a power failure

and possibly losing a count.

Calibration pulses, reverse power, earth loop tamper and

active channel information is displayed via four LEDs fitted on

the module.

Using the SA2007M, the rated conditions of the meter as well

as the LED pulse rate and counter resolution can be selected

for a particular meter design. The meter manufacture is thus

THE SA2007 SERIES ENERGY METER ICS

THE SA2007M PIN PROGRAMMABLE MONOCHIP

METER

sames

Application Note:

Energy Meter Evaluation Module

PM2007M/PPE

able to produce a range of meters utilizing the same counter

and the same metering constant with a single integrated

circuit. Calibration of the meter is done with trim-pots or

resistor ladders. Table 1 gives a short list of all the possible

meter configurations possible with the SA2007M using the

PM2007M/PPE module. Note that the values of the current

transformer’s termination resistor will change to make some of

the rated conditions possible. This will be covered in the

Analog Section.

Table 1: A summary of the pin settings possible with the

SA2007M. Pin status 0 indicates connects to VSS and 1

indicates connection to VDD

THE SA2007P MONOCHIP METER WITH EEPROM

CALIBRATION

The SA2007P uses an external EEPROM to store calibration

data as well as meter specific settings. A major advantage of

the SA2007P is that no external trim-pots or resistor ladders

are required to calibrate the meter. This greatly enhances the

meter reliability and can improve meter production times if

used in an automatic meter calibration system.

The SA2007P integrated circuit together with an external

EEPROM provides more meter setup features than the

SA2007M. Additional information regarding the meter (serial

numbers, client, and manufacture date) can also be stored in

the unused sections of the EEPROM memory. An IIC bus

based EEPROM is used to store configuration and meter

setup data for the SA2007P. The SA2007P will load this data

from the EEPROM during power up. During normal meter

operation it periodically reloads the data from the EEPROM.

The SA2007P never writes to the EEPROM. For more specific

configuration information please refer to the SA2007P

datasheet.

1/16

Setting

20A / 230V

40A / 230V

60A / 230V

1 pulse / kWh

10 pulse / kWh

100 pulse / kWh

Pin Status

RATED = 0

RATED = Open

RATED = 1

MP1=0,MP0=0

MP1=0,MP0=1

MP1=1,MP0=0

SPEC-0942 (REV. 4)

21-02-03