Tempco TEC-410, Инструкция по эксплуатации

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The controller can output (retransmit) the process value via its retransmission
terminals RE+ and RE- provided that the retransmission option is ordered.A
correct signal type should be selected for COMM parameter to meet the
retransmission option installed. AOLO and AOHI are adjusted to specify the
low scale and high scale values of retransmission.
3-9 PV Retransmission
3–10 Data Communication
The controller support RTU mode of Modbus protocol for
data communication. Other protocols are not available for
the TEC-410.
Two types of interface are available for data communica-
tion. These are RS-485 and RS-232 interface. Since RS-
485 uses a differential architecture to drive and sense sig-
nal instead of a single-ended architecture like the one used
for RS-232, RS-485 is less sensitive to noise and suitable
for communication over a longer distance. RS-485 can
communicate without error over a 1km distance while RS-
232 is not recommended for a distance of over 60 feet (20
meters).
Using a PC for data communication is the most economi-
cal method. The signal is transmitted and received through
the PC communication port (generally RS-232). Since a
standard PC can't support an RS-485 port, a network
adapter (such as TEC99001) has to be used to convert RS-
485 to RS-232 for a PC if RS-485 is required for data com-
munication. Up to 247 RS-485 units can be connected to
one RS-232 port; therefore a PC with four comm ports can
communicate with 988 units.
S etup
Enter the setup menu. Select RTU for COMM. Set individ-
ual addresses for any units that are connected to the same
port. Set the baud rate (BAUD), data bit (DATA), parity bit
(PARI) and stop bit (STOP) so that these values are accor-
dant with PC setup conditions.
If you use a conventional 9-pin RS-232 cable instead of
TEC99014, the cable should be modified for proper opera-
tion of RS-232 communication according to section 2-9.
Refer to Chapter 7 for a complete technical description of
the Modbus Communications Protocol.