- General Electric Computer Accessories User Manual

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• Chapter 5 Signal Mapping Innovation Series Medium Voltage GP Type - G Drives GEH-6385
Variable Mapping
Also refer to “Variable
Maps” in this chapter.
The drive software uses variables either of two ways:
As dynamic references for controlling the drive
• To contain feedback on the drive status
For example, the variables Speed Feedback and Speed Reference are associated with
the speed regulator function.
The variable map is defined in terms of paired pages, as follows:
Page Type Direction of Data
Reference From the controller to the drive (for example, Speed Reference)
Feedback From the drive to the controller (for example, Speed Feedback)
Each element in the map is assigned a data type, used by standard assignments as
follows:
Data Type Format
Real 32 bits per IEEE 754 (23-bit mantissa, 8-bit exponent, 1-bit sign)
Boolean 1 bit per signal
The following table specifies variables that indicate the LAN health and status for
the LAN Configuration and Health function.
Variable Description
LAN connection OK Indicates that the health of the LAN connection is good,
such that the LAN watchdog function is satisfied.
LAN commands OK Indicates that the health of the LAN references are good,
based upon the detection of two successive LAN
connection OK indications.
Heartbeat ref, LAN LAN heartbeat signal that is generated by the controller.
The drive can be configured to alarm or trip upon the
failure of this heartbeat. The drive also echoes this signal
back out the Heartbeat Fbk LAN variable.
Heartbeat Fbk, LAN Drive echoes the Heartbeat ref variable out on Heartbeat
Fbk.
Sys ISBus error Cnt Not applicable
Sys ISBus error Reg Not applicable
Frame PLL OK status Not applicable
FPLL Freq Output Not applicable