Eaton SWIRE-GW-MB, Manual, Page: 25 / 67

Potential separation
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07/09 MN03407002Z-EN
Potential separation The following electrical isolation measures apply for the
SWIRE-GW-MB interfaces:
• Potential isolation of the MODBUS-RTU to the supply
voltage and to the SmartWire system
• No isolation between the supply voltage for the gateway
and the supply voltage for the contactor coils
• No electrical isolation between the supply voltages and
the SmartWire system.
Max. cable lengths For each communication standard (RS232 and RS485)
maximum bus cable lengths are specified.
RS485
When RS485 is used, the maximum cable length depends on
the cross-section of the data cable. At a conductor cross-
section of 0.25 mm² (AWG24) or greater, the maximum
cable length is 1000 m. With data cables of category 5, the
bus length can be up to 600 m.
RS232
For the RS232 standard and a cable capacitance of u to
2500 pF the following maximum cable lengths are specified.
Table 5: Maximum cable lengths for RS232
Baud rate [kBit/s] Max. cable length [m]
9.6 152
19.2 15
38.4 7.5
57.6 5