Rockwell Automation T8840 Trusted Temperature FTA - Manual (Page 7)

Trusted
TM
Temperature FTA T8840
Issue 4 Apr 10 PD-T8840 7
2. Installation
2.1. Cable Selection
The Trusted TM Temperature FTA can connect direct to an Analogue Input Module using either
companion cables TC-211/212 or smart-slot cables TC-511/512. The Output can also be connected to
the Analogue Input module via a VFTA if necessary to be compatible with an existing installation.
Some isolator modules will float their output to 10V on an open circuit field input. This will cause slice
faults on the analogue input module. If the isolator output is connected to the module via a 250R
resistor on a VFTA, the voltage will be pulled down into the module’s operating range. Therefore even
if the isolator output is a voltage signal, it is recommended to connect the input via a VFTA with the
250R VFTA resistor in parallel.
Figure 2 System connectivity using 1-5v output devices
Analogue
module
8431/ 8432
Temperature
FTA
8840
Temperature
FTA
8840
Temperature
FTA
8840
Temperature
FTA
8840
Temperature
FTA
8840
TC-211/212
Typical Configuration using conditioning
Devices with 1-5v output
Up to 8 temperature devices