Pepperl+Fuchs KFD Series, Руководство пользователя

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HART Multiplexer System KFD*-HM*-16
Mounting and Installation
4.4.3 Connecting the Multiplexer Master to a Computer
The multiplexer master is connected to the computer via an RS-485 interface.
Connecting the Multiplexer Master to a Computer
1. Connect a computer or a process control system to terminals 13, 14, and 15.
Observe the tightening torque for the terminal screws. The tightening torque is
0.5 Nm to 0.6 Nm.
Do not exceed a maximum cable length of 1200 m. Use a shielded, twisted, two-core cable.
2. In the case of long cable lengths and high baud rates, install a terminator at each end of the
RS-485 line. Use terminators of 120  to 220  .
If the RS-485 line ends at the multiplexer master and is not routed to other devices, use the
second RS-485 connection at terminals 20 and 21 to connect a terminator.
If you use an interface converter, install a terminator on the interface converter and an
interface converter at the other end of the line.
In the case of short cable lengths and low baud rates, no terminators are required.
Observe the RS-485 specifications.
3. Connect additional participants to terminals 19, 20, and 21.
Observe the tightening torque for the terminal screws. The tightening torque is
0.5 Nm to 0.6 Nm.
Do not exceed a cable length of 1200 m. Use a shielded, twisted, two-core cable.
Terminal Designation Meaning
13, 19 Shield Cable shielding
14, 20 RxD/TxD - (RS-485 B
–
) RS-485 differential signal
15, 21 RxD/TxD + (RS-485 B+)
Table 4.1 Connector assignment for removable terminals
Caution!
Risk of electric shock or property damage due to inadequate grounding
If the cable shield is not connected to the protective earth correctly, this may result in potential
equalization currents. These currents may injure operating personnel or cause property
damage.
Ground the cable shield at only one end of the line. Observe the applicable laws, standards,
and directives for the operating location.
Note!
To connect the multiplexer master and computer, you need an interface converter.
Different interface converters are required depending on the connection on your computer.
We recommend the following converters:
•
Interface converter from RS-485 to RS-232: Telebyte model 285, from Telebyte
• Interface converter from RS-485 to RJ45, Com-+, from W&T
• Interface converter from RS-485 to USB: I-7561-CR, from ICP