Rockwell Automation 7000 PowerFlex Medium Voltage AC Drive (B Frame) - Classic Control - Manual (Page 294)

6-4 Component Definition and Maintenance
7000-UM150I-EN-P – June 2013 7000 “B” Frame
Voltage-Sensing Assembly
The voltage-sensing assembly consists of the voltage sensing board
and the mounting plate. The voltage sensing board has six independent
channels which convert voltages up to 10800V (7.2kV x 1.5 pu)
down to low voltage levels which can be used by the PowerFlex
7000 control logic (i.e. Signal Conditioning Board - SCB). Two of
these assemblies can be linked together where one assembly acts as
the master assembly, and the second assembly acts as the slave
assembly. In this manner, up to twelve independent voltage channels
can be measured. When two assemblies are linked together, the
master assembly is used to send the twelve voltage signals to the
SCB board. For drives that require the synchronous transfer option,
one additional module is used. This assembly uses a separate
connector to output the transfer voltages directly to the SCB board.
Below is a table of the input voltage ranges for each of the input
terminals on the voltage-sensing board. There are four separate
inputs taps for each of the six independent channels. This assembly
has been designed to operate at a nominal input voltage of up to
7200V with a continuous 40% overvoltage. The output voltages are
scaled to provide close to 10V peak for a 140% input voltage at the
high end of each of the voltage ranges.
Each of the channels has only four taps, thus they must be used to
provide a range of input voltages and software will be used to
provide a given amount of gain so that 140% will correspond to the
maximum numerical value of the analogue to digital converter.
Table 6.A – Input Voltage Ranges
Tap Voltage Range
D 800 - 1449V
C 1450 - 2499V
B 2500 - 4799V
A 4800 - 7200V
A T T E N T I O N A T T E N T I O N Grounds must be reconnected on the voltage
sensing boards. Failure to do so may result in
injury, death or damage to equipment.