25

Transmitting Data From the Meter

Data is transmitted from the meter in response to either a transmit command

(T), a print block command (P) or User Function print request. The response

from the meter is either a full field transmission or an abbreviated transmission.

See Abbreviated Printing () parameter.

Full Transmission



These characters only appear in the last line of a block print.

The first two characters transmitted (bytes 1 and 2) are the unit address. If the

address assigned is 00, two spaces are substituted. A space (byte 3) follows the

unit address field. The next three characters (bytes 4 to 6) are the register

mnemonic. The numeric data is transmitted next.

The numeric field (bytes 7 to 18) is 12 characters long. When the requested

value exceeds eight digits for count values or five digits for rate values. Byte 8

is always a space. The remaining ten positions of this field (bytes 9 to 18)

consist of a minus sign (for negative values), a floating decimal point (if

applicable), and eight positions for the requested value. The data within bytes 9

to 18 is right-aligned with leading spaces for any unfilled positions.

The end of the response string is terminated with <CR> (byte 19), and <LF>

(byte 20). When a block print is finished, an extra <SP> (byte 21), <CR> (byte

22), and <LF> (byte 23) are used to provide separation between the transmissions.

Abbreviated Transmission



These characters only appear in the last line of a block print.

The abbreviated response suppresses the address and register mnemonics,

leaving only the numeric part of the response.

Meter Response Examples:

1. Address = 17, full field response, Input A = 875

17 INA

875 <CR><LF>

2. Address = 0, full field response, Setpoint 2 = -250.5

SP2

-250.5<CR><LF>

3. Address = 0, abbreviated response, Setpoint 2 = 250, last line of block print

250<CR><LF><SP><CR><LF>

Auto/Manual Mode Register (MMR) ID: U

This register sets the controlling mode for the outputs. In Auto Mode (0) the

meter controls the setpoint and analog output. In Manual Mode (1) the outputs

are defined by the registers SOR and AOR. When transferring from auto mode

to manual mode, the meter holds the last output value (until the register is

changed by a write). Each output may be independently changed to auto or

manual. In a write command string (VU), any character besides 0 or 1 in a field

will not change the corresponding output mode.

U abcde

e = Analog Output

d = SP4

c = SP3

b = SP2

a = SP1

Example: VU00011 places SP4 and Analog in manual.

Analog Output Register (AOR) ID: W

This register stores the present signal value of the analog output. The range

of values of this register is 0 to 4095, which corresponds to the analog output

range per the following chart:

*Due to the absolute

accuracy

rating

and

resolution of the output

card, the actual output

signal may differ 0.15%

FS from the table values.

The

output

signal

corresponds to the range

selected (0-20 mA, 4-20

mA or 0-10 V).

Writing to this register (VW) while the analog output is in the Manual Mode

causes the output signal level to update immediately to the value sent. While in

the Automatic Mode, this register may be written to, but it has no effect until the

analog output is placed in the manual mode. When in the Automatic Mode, the

meter controls the analog output signal level. Reading from this register (TW)

will show the present value of the analog output signal.

Example: VW2047 will result in an output of 10.000 mA, 12.000 mA or

5.000V depending on the range selected.

Setpoint Output Register (SOR) ID: X

This register stores the states of the setpoint outputs. Reading from this

register (TX) will show the present state of all the setpoint outputs. A “0” in the

setpoint location means the output is off and a “1” means the output is on.

X abcd

d = SP4

c = SP3

b = SP2

a = SP1

In Automatic Mode, the meter controls the setpoint output state. In Manual

Mode, writing to this register (VX) will change the output state. Sending any

character besides 0 or 1 in a field or if the corresponding output was not first in

manual mode, the corresponding output value will not change. (It is not

necessary to send least significant 0s.)

Example: VX10 will result in output 1 on and output 2 off.

Byte

Description

1-12 12 byte data field, 10 bytes for number, one byte for sign, one byte

for decimal point

13

<CR> (Carriage return)

14

<LF> (Line feed)

15

<SP> (Space)

16

<CR> (Carriage return)

17

<LF> (Line feed)

<LF> (Line feed)

23

<CR> (Carriage return)

22

<SP> (Space)

21

<LF> (Line feed)

20

3 byte Register Mnemonic field

4-6

<SP> (Space)

3

12 byte numeric data field: 10 bytes for number, one byte for sign, one

byte for decimal point

7-18

2 byte Node (Meter) Address field [00-99]

1, 2

<CR> (Carriage return)

19

Description

Byte

10.000

20.000

9.9975

19.996

5.000

12.000

0.0025

4.004

0.000

4.000

0-10V

4-20 mA

20.000

4095

19.995

4094

10.000

2047

Output Signal*

Register Value

0.005

1

0.000

0

0-20 mA