Bently Nevada 3300/01 Series, Руководство по эксплуатации

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System Monitor
Message Response Time (msec)
ACK or NAK 2
BCD 7 *
Binary
6 *
80175-01
16 PROTOCOL SPECIFICATIONS
ALLEN BRADLEY PROTOCOL DATA FORMAT
Internally the Serial Interface converts the backplane multiplexed static data signal into a digital
value using an 8-bit analog-to-digital convertor. When an analog data request message is received
on Allen Bradley full duplex protocol, this 8-bit value is shifted left four bits to represent a 12-bit
value. If the BCD switch is set ON on SW3, then this 12-bit value is converted to a four place
binary coded decimal number and placed in the message response. The least significant digit is
always zero. If the BCD switch is OFF, the 12-bit binary number is returned in the message.
Since the maximum value the 8-bit convertor can have is 255, then the maximum 12-bit value is
255(16) = 4080. The least significant four bits of the 12-bit binary word are always zero.
ALLEN BRADLEY PROTOCOL MESSAGE RESPONSE TIMES
The following specifications define the typical measured response times for messages. The
response time is the time from the end of the last received message to the beginning of the
subsequent response message. It does not include message transmission times.
* full 36 word read
ALLEN BRADLEY PROTOCOL IMBEDDED RESPONSES
The Serial Interface implements imbedded responses with Allen Bradley protocol. It will accept
imbedded responses within incoming messages and it may insert imbedded responses in out-
going messages.
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