Emerson 375 User Manual page 48

3-12 HART Functionality
There are three terminals on the top of the 375
Field Communicator. Two of them are red and one
of them is black. Each red terminal is a positive
connection for its protocol. The black terminal is a
common shared by both protocols. There is an
access door to ensure that only one pair of
terminals is exposed at any one time; see Figure
3-1. There are several markings to indicate which
pair of terminals is for which protocol.
Figure 3-1. HART terminal access door
HART Terminal Markings