Fisher-Rosemount HART 275, Руководство по эксплуатации продукта

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1-1
SECTION 1
The HART
®
Communicator
INTRODUCTION
The HART (Highway Addressable Remote Transducer) Communicator
(Figure 1-1) is a hand-held interface that provides a common communication
link to all HART-compatible, microprocessor-based instruments.
Section 1 discusses the HART Communicator Connections, Liquid Crystal
Display, Keypad, Offline and Online menu, Battery Pack, Memory Module,
data pack 100, Maintenance, and Year 2000 Compatibility. It also includes
short overviews on some of the Communicator’s functionality.
Section 2 describes tasks that are common to Fisher-Rosemount’s HART
devices and includes some of the common screen displays.
Section 3 displays typical examples of menu trees specific to Fisher-
Rosemount products.
Your HART Communicator interfaces with any HART-compatible device from
any wiring termination point using a 4–20 mA loop, provided a minimum load
resistance of 250 ohms is present between the Communicator and the power
supply. Your HART Communicator uses the Bell 202 frequency shift key
(FSK) technique of high-frequency digital signals superimposed on a
standard transmitter current loop of 4–20 mA. Because the total high-
frequency signal voltage added to the loop amounts to zero, communication
to and from a HART-compatible device does not disturb the 4–20 mA signal.
FIGURE 1-1. The HART Communicator.
FUNCTION KEYS
ACTION KEYS
ALPHANUMERIC KEYS
SHIFT KEYS
LIQUID CRYSTAL DISPLAY (LCD)