FBM207B

Discrete inputs can be sensed across all the usual voltage levels found in industrial facilities. The FBM207/b/c uses one of the several termination assemblies to match to the externally powered voltage level. In cases where the inputs are critical to the plant’s control scheme, the FBM 207/b/c may be installed as a redundant pair with standard control blocks used to manage the redundancy.
OVERVIEW
The FBM207/b/c Voltage Monitor/Contact Sense Input Module functions as a 16-channel DC voltage monitor or 16-channel contact sensor. Each channel accepts a 2-wire input from a DC voltage source (FBM207) or pair of contacts or solid state switches (FBM207b/ FBM207c). Associated termination assemblies (TAs) support discrete input signals at voltages of 60 V DC, 120 V AC/125 V DC, or 240 V AC. For voltages higher than 60 V DC, the TAs have additional signal conditioning hardware that provides voltage attenuation and optical isolation.

Each discrete input is galvanically isolated from other channels and ground. Group isolated when used with external excitation.
The module performs signal conversion required to interface electrical input signals from field sensors to the redundant module Fieldbus. In addition, it executes programs for Discrete Input, Ladder Logic, Pulse Count, and Sequence of Events, with configurable options of Input Filter Time.
The module can be used as a single unit, or as a redundant pair (two FBM207s). When used as a redundant pair, the modules combine to provide redundancy at the Fieldbus Module (FBM) level, with field input signals received from one common termination assembly though a redundant adapter affixed to the FBMs’ baseplate. The input current for redundant modules is doubled. A redundant digital input block in the Foxboro Evo™ Control Software validates each input in conjunction with information to/from the module, and selects the input with the highest quality for processing in the control strategy. In a redundant configuration, contact sense power from each module is diode OR’d together in the redundant adapter to assure redundant power.