Rockwell Automation 1797-IRT8 FLEX Ex Thermocouple/RTD/mV Input Module User Manual - Manual (Page 62)

Publication 1797-6.5.2 - February 2001
6-8 Applying FLEX Ex Thermocouple/RTD/mV Input Modules
I/O
The 1797-IRT8 module complies fully to and provides simple entity
parameters. This module can directly interface with a wide variety of
intrinsically safe controls and instrumentation. Because all field device
power is supplied directly from the I/O module, no extra wiring or
power sources are needed in a hazardous area.
Finally, these modules maintain intrinsic safety in hazardous areas by
providing isolation from other modules in the system as well as
intrinsic safety segregation between channels on the same module.
Optimize Power
Distribution Your FLEX Ex system must use adequate power supplies to support
the physical locations determined earlier in this chapter. Each FLEX Ex
I/O module in the system is rated for input power, and the FLEX Ex
power supply is rated in the number of output channels and power
available from each channel.
Assigning Power Supplies
Note the amount of power each module requires and assign it to a
power supply output. Continue to assign modules to the power
supply output until the supply’s output power rating is consumed.
The graphic below shows the number of modules per power supply
output.
Modules
0
5
3
2
1
4
IRT8
1.6W
IRT8
1.6W
IRT8
1.6W
IRT8
1.6W
IRT8
1.6W
IRT8
1.6W
IRT8
1.6W
IRT8
1.6W
IRT8
1.6W
IRT8
1.6W
IRT8
1.6W
IRT8
1.6W
41661
IBN16
2.8W
IBN16
2.8W
IBN16
2.8W
IBN16
2.8W
IBN16
2.8W
IBN16
2.8W
IBN16
2.8W
IJ2
4.25W
IJ2
4.25W
IJ2
4.25W
IJ2
4.25W
OE8
6.3W
IE8
7.5W
ACNR
8.5W
RPFM
(In
RPFM
(In
RPA
8.5W