Eaton Power Xpert Meter 4000, Быстрый старт

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The maximum system capacity is 4,000 feet of communication cable and 32 devices.
Make sure the twisted pair wire is recommended for RS485 network use. For reference,
review the RS485 wiring spec for wiring specifications.
Tie the communication cable shield to ground only once at the RS485 master device.
3.13. RS485 Cable Characteristics
Make sure the twisted pair wire is recommended for RS485 applications:
• Single twisted pair for data 18-24AWG
• Shield consiting of aluminized Mylar & partial coverage braid with drain wire
• Characteristic impedance ~ 120 ohms
• Data L-L capacitance ~12pf/Ft.
• Typical ratings are 75C and 300V NEC CM
• Belden Data Tray series 3074F is 600V NEC TC
3.14. RS485 Wiring Basics
The maximum system capacity is 4000 ft. of cable and 32 devices. The baud rate can
restrict the maximum cable length.
• Wiring is done in a strict daisy chain without taps or stars
• 120 ohm 1/4W end of Line Termination Resistors (EOLTR) are required at each
end of the cable
• Attach like terminals to like terminal types for each RS485 port being net -
worked.
• Tie the communication cable, shield to ground, at one location only.
• Data line definition - As per the RS485 standard - In an idle marked state (logic
1) Data B (+) will be electrically > than Data A (-)
Note: When connecting to third party RS485 devices their data line nomenclature may be
inverted. If the RXD LED is on continuously, this indicates a crossed data pair.
• The use of ferrules to terminate the cable ends is strongly recommended to
minimize problems with frayed wires and to strengthen the terminal block con-
nection, when daisy chaining wires use a dual wire ferrule.
Phoenix Contact and many other vendors carry ferrules and crimping tools for this pur-
pose.
For more information about RS485 wiring, please refer to TD 17513, Eaton Electrical field
Devices Communication Wiring Specification.
METER AND DISPLAY MODULE ENVIRONMENTAL RATINGS
Display Module Face – UL50/NEMA Type 12, IP42
•
Pollution Degree III
• Temperature Range -20 to 60° C
• The panel enclosure must be Type 12, IP42 or better and the mounting surface flat, to
preserve Display type/IP rating
• The Type12, IP42 rating requires that the Ethernet port cover is secured to display or
the Ethernet cable is connected.
Display Module Back – UL50/NEMA Type 1, IP30
•
Pollution Degree II
Meter Module – UL50/NEMA type 1, IP30
•
Pollution Degree II
Page 26
IB02601007E
www.eaton.com
3 Mounting and Wiring