2.13 Field Termination Assembly
Terminal Connectors
Terminal connectors on the (FTA) provide the connection points for the process control wiring to sense,
condition, or operate the connected device. Depending upon the type of FTA, fuses, relays, and resistors
protect the FTA circuitry. The FTA communicates with an associated IOP, which in turn communicates
with the HPMM(s).
FTAs types
Standard types of FTAs, as described in Table 3 Standard Field Termination Assembly Types, interface
the field wiring and provide communication with an associated IOP. They are categorized as "standard"
because types of Galvanically Isolated FTAs are also available as described in Table 4 Galvanically
Isolated Field Termination Assembly Types.
Model and part numbers
The model and part numbers for available individual FTAs of each type can be found in the "Spare
Parts" section.
Detailed descriptions
Refer to the Process Manager I/O Installation manual for a detailed description of each FTA.
Standard FTAs
Standard type FTAs are listed in the following table.
FTA Type
High Level Analog Input/
Smart Transmitter Interface
(HLAI/STI)
High Level Analog Input
(HLAI)
Smart Transmitter Interface
(STI)
Low Level Analog Input
(LLAI)
Low Level Analog Input
Multiplexer
(LLMux or RHMUX)
Analog Output (AO)
Analog Output (AO) HART
120 Vac Digital Input (DI)
R688
December 2020
Table 3 Standard Field Termination Assembly Types
Accepts high level analog inputs. The inputs are configurable as single-ended or
differential in relation to logic common. This FTA is also used to interface a Smart
Transmitter device.
Accepts high level analog inputs. The inputs are configurable as single-ended or
differential in relation to logic common.
Interfaces with Smart Transmitter devices. The interface is referenced to logic
ground. The Smart Transmitter provides field isolation.
Can be configured to accept low-level or high-level analog inputs. Low-level analog
inputs include Thermocouples (TC), Resistance Temperature Detectors (RTDs), or
millivolt sources. High-level inputs such as voltage sources (0-5 V) and 4-20
milliamp current loop devices are acceptable.The inputs are isolated from each
other and the HPM, but share a common bus for field wire shields.
The FTA accepts one set of low-level analog inputs, such as thermocouples (TC)
or Resistance Temperature Detectors (RTDs). The set of inputs must be either
thermocouples or RTDs. The inputs are sequentially multiplexed. One or two FTAs
of either type can be connected to one Power Adapter assembly and its IOP.
Provides 4-20 mA analog outputs to proportioning loads such as valves.
Provides 4-20 mA outputs, and incorporates circuitry to allow HART field devices
to be connected to the FTA without using external filters. These FTAs also provide
a connector for an external HART multiplexer.
Accepts ac digital inputs. All inputs are isolated from each other. Two versions of
the FTA are available, with and without pluggable input modules.
HPM High-Performance Process Manager Service
Honeywell
2 Equipment Description
2.13 Field Termination Assembly
Description
75