User manual for meter with U/I input PD72S
7.3.7.
“rS” menu
This menu is connected with RS-485 interface, and sets his properties:
“Addr”
- this parameter defines the address of the device, accordingly to Modbus protocol. It
can be set in range from 0 to 199. If the value 0 is set then device, responds to frames
with address 255 (FFh).
“bAud”
- this parameter determines RS-485 interface baud rate. It can be set to one of 8
possible values:
“1.2”
,
“2.4”
,
“4.8”, “9.6”
,
“19.2”
,
“38.4”
,
“57.6”
,
“115.2”
, which
respond to the baud rates of 1200, 2400, 4800, 9600, 19200, 38400, 57600 and
115200 bit/sec respectively.
“mbAc”
- this parameter sets the access to the configuration registers of the device. Possible
values:
“on”
- configuration registers can be set via RS-485 interface,
“oFF”
- configuration registers cannot be set via RS-485 interface.
The access to registers no 04h i 05h can’t be denied by
“mbAc”
parameter
(see:
LIST OF REGISTERS
).
“mbtO”
- this parameter defines maximal time (sec) between following frames received by
the device. If the delay will be greater than the value of
“mbtO”
parameter, the
relays which are controlled via RS-485 interface, will set to alert state (see
“rEL1”
menu
des
cription). Parameter “
mbtO
” can be set to values from 0 to 99 seconds.
The value 0 means that the time will be not controlled.
“rESP”
- this parameter defines minimal (additional) delay between the Modbus message
and the answer of the device (received and sent via RS-485 interface). This
additional delay allows the device to work with poor RS-converters which do not
works properly on baud rates higher than 19200. This parameter can be set to one of
values:
“Std”
- answer as quick as possible, no additional delay
“10c”
“20c”
“50c”
“100c”
“200c”
- answer delayed of 10, 20, 50, 100 of 200 chars respectively,
where one character time depends on selected baud rate
In the most cases parameter
“rESP”
should be set to
“Std”
(no additional delay).
Unfortunately for some third party RS-converters
“rESP”
should be adjusted
experimentally. Table 7.1 contains most frequently used values.
“bAud” parameter
“38.4”
“57.6”
“115.2”
“rESP” parameter
“10c”
“20c”
“50c”
Tab.7.1.
Settings of
“
rESP” parameter
30
