Eaton Power Xpert PXM 4000, Руководство пользователя и инструкция по установке

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A MODBUS Communication
A.10. Registers 4611-6332 (Real-Time Measured Values)
See Appendix B for detailed listing.
A.11. Register 11000+ (Real-Time and Historic Meter Data)
See Appendix B.
A.12. Types of Data
FLOATING-POINT (IEEE-754)
Power Xpert Meter makes extensive use of the IEEE-754 floating-point format for real-time
and historic data. The standard representation requires a 32-bit word. The first bit is the
sign bit, S, the next eight bits are the exponent bits, E, and the final 23 bits are the fraction
F:
S EEEEEEEE FFFFFFFFFFFFFFFFFFFFFFF
The value represented by the word may be determined as follows:
• If E=255 and F is nonzero, then V=NaN (“Not a number”)
• If E=255 and F is zero and S is 1, then V=-Infinity
• If E=255 and F is zero and S is 0, then V=Infinity
• If 0<E<255 then V=(-1)
S
* 2
(E-127)
* (1.F) where 1.F is intended to represent the binary
number created by prefixing F with an implicit leading 1 and a binary point.
• If E=0 and F is nonzero, then V=(-1)
S
* 2
(-126)
* (0.F). [un-normalized value]
ENERGY FORMAT (64-BIT)
Energies are represented in a 64-bit format that includes a multiplier (2
MantissaMultiplier
) for
scaling and engineering units (10
EngineeringUnits
) . If energy were merely kiloWatt-hours, the
MantissaMultiplier equals 0 and Engineering Units equal 3. For further system simplicity,
these should be constants such that the ModBus master does not need to repetitively read
them.
LIST OF TRIGGER EVENTS
Starting at Reigster 18620 is a list of the 20 ost recent triggered events.
32-bit EventID
Timestamp UTC/GMT)
Cause (see Register 4610 for definitions)
Param 1, Param 2, IEEE floating-point values that are related to the event-if applicable.)
EVENT LOG
Starting at Register 29000 is a list of the 20 most recent logs.
EventID (32 bit)
Timestamp (UTC/GMT)
Number of ASCII characters in logged ddescription (16 bit)
Logged Description (ADCII string of up to 150 characters)