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SA2002P

Description

E Address

2

Contents

Bit [7:0]

Name

Pre-Divider

Rated Condition

Counter Resolution (LSB)

Counter Resolution (MSB)

Counter Pulse-Width

12

13

14

14

14

15

16

17

18

19

20

21

22

22

23

Cor

XOR of ADDR 12

Ct

Ds

Dc

XOR of ADDR 14

Kr

XOR of ADDR 16

Cled

XOR of ADDR 18

CresL

XOR of ADDR 20

ClresH

Pw

XOR of ADDR 22

---v vvvv

xxxx xxxx

---- ---v

---- -v--

---- v---

xxxx xxxx

vvvv vvvv

xxxx xxxx

---- --vv

xxxx xxxx

vvvv vvvv

xxxx xxxx

---v vvvv

vv-- ----

xxxx xxxx

D12

D14

D14

D14

D16

D18

D20

D22

Creep current threshold

Metering direction select

DC or AC measurement mode

Led Pulse-rate

KEY: (- = DON’T CARE); (V = VALUE/PARAMETER); (0,1 = LOGICAL VALUE); (X = BIT-XOR)

DEVICE CONFIGURATION

SIGNAL FLOW DESCRIPTION

The following is an overview of the SA2002P’s registers. For a

detailed description of each parameter please refer to

parameter description section.

Figure 8 shows the various registers in the SA2002P’s power

to pulse rate block. The input to this block is a single bit pulse

density modulated signal of 641454 pulses per second at rated

conditions. The parameters

and

contain values which are read from the

external EEPROM during power up.

The divider registers,

and

, are

used for gain calibration. The

register

is used to set the SA2002P’s creep threshold.

register is also used to program the rated condition

of the meter and feeds the registers

and

with the applicable pulse rate. These two

registers are programmed to select the LED output rate and

the counter resolution (pulses per kWh) respectively. The

register is used to program the pulse

width for the mechanical counter driver output MOP and MON.

Cor, Ct, Kr, CresH, CresL, Pw,

Cled, Dc

Ds

Pre-Divider

Rated Condition

Creep current threshold

The Rated

Condition

LED-constant

Counter Resolution

Counter Pulse Width

EEPROM Memory Allocation

The following table shows the EEPROM memory allocated as

Pre-Divider

÷Cor

Test Mode

Tm

AC/DC Mode

Dc

Metering Direction

Ds

Rated Condition

÷Kr

Counter

Resolution

CresH, CresL

LED-Constant

Cled

Counter Pulse

width

Pw

MOP

MON

LED

Normally 6400p/kWh

Normally 1253p/s

Power from

converters

641454 pulses/s

S - D

Creep current

threshold

detector

Ct

Figure 8: Signal flow block diagram

well as the corresponding name. The uneven byte always

contains a XORed byte of the previous even byte. This is the

checksum byte used by the SA2002P to ensure data integrity.

Table 1: EEPROM memory allocation map