Bently Nevada 3300/01 Series, Руководство по эксплуатации

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System Monitor
Data Type Rack Starting Address
DIRECT VALUES
MONITOR STATUS 8 ( 1 0 Octal)
48 (60 Octal)
80175-01
16
PROTOCOL SPECIFICATIONS
ALLEN BRADLEY PROTOCOL DATA ADDRESSING
The Serial Interface uses fixed protocol addresses for the starting locations of rack data. These
addresses are n o t the physical addresses o f the data in the interface memory. They are the
addresses used in the protocol messages to access data which is available from the interface. The
protocol starting addresses are
Note 1
For addressing purposes, a 2-channel double-wide monitor looks like a 2-channel
single-wide monitor in the left slot followed by an empty right slot. A single channel
monitor will b e treated as a dual channel monitor with a n invalid data value for
channel 2.
Note 2
At the message level, Allen Bradley protocol refers to addresses as byte addresses
whereas Serial Interface addresses a r e w o r d b a s e d ( 2 bytes). Therefore, t h e
address that is placed into the protocol message is the word address multiplied by
two. Byte addresses will always be even. Also the byte count at the message level
is the word count multiplied by two.
DIRECT VALUES
Direct values occupy contiguous protocol addresses. The starting address for the direct values
is address 8. This is the address of the first direct value of the first monitor location in the rack.
The first monitor (slot 1) is the left most monitor just to the right of the System Monitor. The entire
rack's direct values are found sequentially in adjacent addresses. Each monitor will have
direct values associated with it unless it is a 6-channel monitor. In that case, it will have 6 direcf
values. The presence of 6 -channel monitors will b e indicated b y the SW3 switch o n the Serial
Interface circuit board. Channel direct values are ordered first channel to last channel. Once the
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