Allen-Bradley 857-RAA, User Manual

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26 Rockwell Automation Publication 857-UM002C-EN-P - February 2018
Chapter 4 Configure the Base 857 Relay
External Analog Outputs for
857-RAD Scanner The 857-RAD scanner is equipped with four individual isolated analog
outputs. If used, these outputs must be configured within the base relay for
proper operations. Each analog output has a fully configurable output current
range. Typical range configurations would be 0…20 mA or 4…20 mA. More
dynamic ranges like 0…1 mA, 0…5 mA, or 10…20 mA can be configured freely
as long as the boundary values are within the 0…20 mA range.
Table 9 - 857-RAA/RAD External I/O Registers
Modbus Register Properties
RTD Channel 1 resistance 301 Read
RTD Channel 2 resistance 302 Read
RTD Channel 3 resistance 303 Read
RTD Channel 4 resistance 304 Read
RTD Channel 5 resistance 305 Read
RTD Channel 6 resistance 306 Read
RTD Channel 7 resistance 307 Read
RTD Channel 8 resistance 308 Read
RTD Channel 9 resistance 309 Read
RTD Channel 10 resistance 310 Read
RTD Channel 11 resistance 311 Read
RTD Channel 12 resistance 312 Read
mA-input 1
(1)
(1) 857-RAD only.
313 Read
mA-input 2
(1)
314 Read
mA-input 3
(1)
315 Read
mA-input 4
(1)
316 Read
PTC-resistance
(1)
317 Read
mA-output 1
(1)
318 Read / Write
mA-output 2
(1)
319 Read / Write
mA-output 3
(1)
320 Read / Write
mA-output 4
(1)
321 Read / Write