Allen-Bradley 857-RAA, Руководство пользователя

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Rockwell Automation Publication 857-UM002C-EN-P - February 2018 7
Chapter
1
Layout
Overview
The Allen-Bradley™ Bulletin 857-RAA and 857-RAD are both 12 channel
RTD scanners. The 857-RAD enhanced scanner also provides support for a
PTC (thermistor) input along with four programmable 0…25 mA current
input channels and four programmable 0…25 mA current output channels that
can be programmed for any analog scale (for example, 0…1mA, 4…20mA,
1…5mA, and so on). Both the 857-RAA and 857-RAD are connected to the
Bulletin 857 relay via ST-type glass fiber optic cables; the 857-RAA uses one
fiber optic cable (only TX) while the 857-RAD uses a dual fiber optic cable
configuration (TX and RX).
The RTD scanners can also be mounted remotely up to 2000 m from the base
857 relay.
Catalog Number Explanation
1 2 3
857 R A A
a b c
a
Scanner Connectivity
R Connection to base 857 relay
b
Basic Scanner Capabilities
A 12 Channel RTD Scanner
c
Supply Voltage, Communications Method, and Capabilities
A
48…264V AC/DC, 50/60Hz
Input power: single-glass, fiber-optic communication
B
48…264V AC/DC, 50/60Hz
Input power: RS-485 communication
C
24V DC input power. Comes with 4+4 configurable mA
outputs/inputs, dual-glass, fiber-optic communications
D
48…264V AC/DC, 50/60 Hz input power. Comes with 4+4
configurable mA outputs/inputs, dual-glass, fiber-optic
communications