DSE DSEGenset DSE8004, Руководство оператора

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Specification
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3.7.1.2 RS232 PORT
NOTE: For direct connection an RS232 null modem (crossover) cable is required. This is
rated to a maximum cable length of 15 m (49 feet).
RS232 is for short distance communication of maximum 15 m (49 feet) and is typically used to
connect the DSE8004 to a single module for remote communications.
The various operating parameters (such as mains voltage, bus frequency, load kW, etc.) of the
system are available to be viewed.
3.7.1.3 RS485 PORT
NOTE: For a single module to module connection and distances up to 15 m (49 feet) the
RS232 connection method is more suitable and provides for a lower cost alternative to RS485
(which is more suited to longer distance connections).
RS485 is used for point-to-point cable connection of more than one device (maximum 20). One
advantage of the RS485 interface is the large distance specification which is 1.2 km when using
Belden 9841 (or equivalent) cable. This allows for a large distance between the DSE8004 and
multiple modules.
3.7.1.3.1 CABLE SPECIFICATION
NOTE: DSE recommend Belden 9841 (or equivalent) cable for RS485 communication.
This is rated to a maximum cable length of 1.2 km. DSE Stock Belden 9841 cable, DSE Part
Number: 016-030.
Description Specification
Cable Type Two core screened and shielded twisted pair
Cable Characteristics
120
Ω
impedance
Low capacitance
Recommended Cable
Belden 9841
Belden 9271
Maximum Cable Length
1200 m (¾ mile) when using Belden 9841 or direct equivalent.
600 m (656 yards) when using Belden 9271 or direct equivalent.
RS485 Topology “Daisy Chain” Bus with no stubs (spurs)
RS485 Termination
120
Ω
. Not fitted internally to module. Must be fitted externally to the
‘first’ and ‘last’ device on the RS485 link.