Eaton PDI WaveStar, Руководство по установке и эксплуатации

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Eaton PDI WaveStar Color Monitor Setup and Operation Manual P-164001109—Rev 01 9
• Run a dedicated ground wire with the signal wires and only ground the shield at one end.
Figure 5. Color Monitor 4-wire Modbus Connections
Color Monitor
or
BMS
Device 1
PDU Board
Devices 2/3
BCMS PCB
Subfeeds
Devices 4/5
BCMS
Panelboards
RX+ TX+ TX+ TX+
RX- TX- TX- TX-
TX+ RX+ RX+ RX+
TX- RX- RX- RX-
33..33 M Mooddbbuuss R RTTU U C Caabblleess
33..33..11 C Caabbllee S Sppeecciiffiiccaattiioonn
RS485/RS422 cable length can be up to 4000 ft. if you use the proper cable:
• The cable resistance should be ≤ 27 ohms/1000ft @ 1 kHz and the mutual capacitance should be ≤ 14pf/ft
@ 1 kHz.
• 4-wire cabling:
– RS422 is typically 4-wire.
– Use a shielded cable with two (2) twisted pairs and a shield/ground wire.
– The two transmit lines must be in one twisted pair and the two receive lines in the other twisted pair.
• 2-wire cabling:
– RS485 is typically 2-wire and is slower than RS422.
– Use a shielded cable with one (1) twisted pair and a shield/ground wire.
33..33..22 C Caabbllee B Biiaassiinngg aanndd TTeerrm miinnaattiioonn
Eaton devices have soft biasing (27K pull-up and pull-down resistors) on the + and – transmit and receive lines.
Therefore, if the customer’s client device allows for control, Eaton recommends that the user turn on biasing
and turn off termination, which may “fight” the biasing. Biasing the client device’s lines is not critical because
the Color Monitor is already biasing the lines. If termination is needed because of an extremely long cable run,
Eaton recommends that a small capacitor be put in series with the terminating resistor.
Color Monitor Networking