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17 ASCII PROTOCOL SUPPORT
The EtherMeter is available with RAW-ASCII protocol support (Optional. ASCII-Version Only).
Many PLC’s and RTU’s are equipped with extra serial ports that are capable of collecting data
from raw ASCII terminal devices such as bar code readers. For compatibility with these PLC’s,
the EtherMeter provides a “Raw ASCII Protocol” output.
When the EtherMeter is set to “Raw ASCII” mode (available via the Setup Menu), the following
data is transmitted from the active serial port every three (3) seconds:
: <TOTAL1> ; <TOTAL2> ; <FLOW1> ; <FLOW2> ; <ROLLOVERS1> ; <ROLLOVERS2> ;
<METER_FAULT1> ;<METER_FAULT2> ; <ANALOG_IN1> ; <ANALOG_IN2> ;
<AUX_DIGITAL_IO_1> ; <AUX_DIGITAL_IO_2> ; <AUX_DIGITAL_IO_3> <CR> <LF>
Each transmission is preceded by a ‘:’ delimiter, and ended with a <CR><LF> delimiter. There
are no spaces or carriage returns between the data fields, as each field is separated by a ‘;’
delimiter.
TOTALIZATION AND FLOW DATA FORMAT:
The EtherMeter was designed in such a way as to simplify and compress the formatting of all
reported data. In order to achieve this level of simplicity, the scale factors (EXP1 and EXP2)
have been stripped from the reported totals (Note: the 2x16 LCD display and web page provide
scaled displays).
For example, consider the following case of an 8-digit register plus two (2) fixed zeros on the right
(EXPn=+2):
RG
B
1 234567
8
00
9
GALLONS
,,,
In this case, the actual total is 1,234,567,800 gallons. However, the ASCII protocol will report the
total as: 12345678. If scaling to GALLONS is desired, then the reading device must perform the
scaling (multiply by 100).
Regarding flow, all reported flow rates are multiplied by 1000 to eliminate the need for floating
point formatting. In this case, if the actual flow rate is 987.6 GPM, then the ASCII protocol will
report the flow as 987600 (MilliGallons Per Minute). If scaling to GPM is desired, then the
reading device must perform the scaling (divide by 1000). Also, keep in mind that all reported
ASCII data is formatted in decimal.
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