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TOTALIZATION AND FLOW DATA FORMAT:
The EtherMeter was designed in such a way as to simplify and compress the formatting of all
reported data. As shown in the previous charts, no floating point or 64-bit registers are
implemented in the ADAM-4000 holding registers, as all data is represented internally as 32-bit
long integers (signed or unsigned) and 16-bit signed integers.
In order to achieve a high level of simplicity and prevent integer overflows, separate exponential
scale factors and multipliers are provided in certain ADAM-4000 registers.
If fully-scaled totalization data is desired, then 64-bit data processing may be required by the
master polling PLC or computer. In most instances, however, 32-bit data manipulation will
suffice.
TOTALIZATION HELPER FORMULAS:
The following calculations are examples helper formulas that may be implemented within the
master. When deciding whether to use 64-bit versus 32-bit data manipulation routines, factor in
the largest expected meter totalization value (meter-specific), and consider that the largest
possible 32-bit unsigned long integer is 4,294,967,295.
Meter 1 Actual Total = [METER 1 TOTAL UNSCALED] x [10
[METER 1 EXPONENT]
]
+ [ROLLOVERS METER 1] x [10
[METER 1 nDIGITS]
] x [10
[METER 1 EXPONENT]
]
= [ADAM-0x00] x [10
[EXP1]
]
+ [ADAM-0x04] x [10
[NDIGITS METER 1]
] x [10
[EXP1]
]
Meter 2 Actual Total = [METER 2 TOTAL UNSCALED] x [10
[METER 2 EXPONENT]
]
+ [ROLLOVERS METER 2] x [10
[METER 2 nDIGITS]
] x [10
[METER 2 EXPONENT]
]
= [ADAM-0x01] x [10
[EXP2]
]
+ [ADAM-0x05] x [10
[NDIGITS METER 2]
] x [10
[EXP2]
]
FLOW RATE HELPER FORMULAS:
The following are possible flow rate helper formulas that may be implemented within a MODBUS
master polling PLC or computer:
Meter 1 Actual Flow = [FLOW 1] / 1000
= [ADAM-0x02] / 1000
Meter 2 Actual Flow = [FLOW 2] / 1000
= [ADAM-0x03] / 1000
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