Serial Communication; Slave - Wachendorff UR3274 Series Manual

9

Serial Communication

9.1

Slave

UR3274U6 is equipped with RS485, it can receive and broadcast
data via serial communication using MODBUS RTU protocol. The
device operates as slave if parameter 59
function enables the control of multiple devices connected to a
supervisory system (SCADA).
Each controller will answer to a master query only if the query
contains same address as on parameter
addresses range from 1 to 254 and there should not be
controllers with the same address on the same line.
Address 255 can be used by the master to communicate with all
the connected equipment (broadcast mode), while with 0 all
the devices receive the command, but no answer is expected.
UR3274U can introduce an answer delay (in milliseconds)
to master request. This delay has to be set on parameter
58
se.de.
storeschange values in the EEPROM memory (100000 writing
cycles), while setpoints are stored with a delay of 10 seconds
after last modification. NB: modifications made to words
different from those described in the following table can lead
to instrument malfunction.
Baud-rate
Format
Supported
functions
At each parameter configuration, instrument
Modbus RTU protocol features
Selectable on parameter 56
4800bit/sec
4.8 k
9600bit/sec
9.6 k
19200bit/sec
19.2k
8, N, 1 (8bit, no parity, 1 stop)
WORD READING (max 20 word) (0x03, 0x04)
SINGLE WORD WRITING (0x06)
MULTIPLE WORDS WRITING (max 20 word) (0x10)
is set as
mast.
The permitted
sL.ad.
28800bit/sec
28.8k
38400bit/sec
38. 4 k
57600bit/sec
57.6k
UR3274U - User manual
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