Sifam Tinsley Theta 30P, Руководство по эксплуатации

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an Earth connection should be made at one point on the network.Loop
(ring) topology does not require any termination load. Line topology
may or may not require terminating loads depending on the type and
length of cable used. The impedance of the termination load should
match the impedance of the cable and be at both ends of the line. The
cable should be terminated at each end with a 120 ohm (1/4 Watt min.)
resistor.
RS 485 network supports maximum length of 1.2km. Including the
Master, a maximum of 32 instruments can be connected in RS485
network. The permissible address range for Power Tranducer is
between 1 and 247 for 32 instruments. Broadcast Mode (address 0)
is not allowed.
The maximum latency time of an Transducer is 200ms i.e. this is the
amount of time that can pass before the first response character is
output.
After sending any query through software ( of the Master) , it must allow
200 ms of time to elapse before assuming that the Transducer is not
going to respond. If slave does not respond within 200 ms, Master can
ignore the previous query and can issue fresh query to the slave.
The each byte in RTU mode has following format:
8-bit binary, hexadecimal 0-9, A-F
2 hexadecimal characters contained in
each 8-bit field of the message
4 bytes (32 bits) per parameter.
Floating point format ( to IEEE 754)
Most significant byte first (Alternative
least significant byte first)
Format of Data Bytes
2 byte Cyclical Redundancy Check (CRC)
Error Checking Bytes
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