KROHNE OPTIWAVE 5200 C_F EN - Manual (Page 123)

DESCRIPTION OF HART INTERFACE
9
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OPTIWAVE 5200 C/F
www.krohne.com 07/2013 - 4001904902 - HB OPTIWAVE 5200 R02 en
9.1 General description
The HART ® Protocol is an open digital communication protocol for industry. It is free to use by
anyone. It is included in the software embedded in signal converters of HART-compatible
devices.
There are 2 classes of devices which support the HART ® Protocol: operating devices and field
devices. There are 2 classes of operating devices (Master): PC-supported workstations (Primary
Master) and manual control units (Secondary Master). These can be used in control centres and
other locations. HART
® field devices include sensors, converters and actuators. Field devices
include 2-wire and 4-wire devices, and also intrinsically-safe versions for use in hazardous
areas.
There are 2 primary operation modes for HART-compatible devices: point-to-point mode and
multi-drop mode.
If the device is used in point-to-point mode, the HART ® Protocol uses the Bell 202 Frequency
Shift Keying (FSK) standard to put a digital signal on top of the 4...20 mA signal. The connected
device sends and receives digital signals that agree with the HART
® Protocol, and sends analog
signals at the same time. Only 1 device can be connected to the signal cable.
If the device is used in multi-drop mode, the network only uses a digital signal that agrees with
the HART
® Protocol. The loop current is set to 4 mA. You can connect a maximum of 15 devices
to the signal cable.
An FSK or HART ® modem is included in field devices and manual control units. It is necessary to
have an external modem for PC-supported workstations. The external modem is connected to
the serial interface.
9.2 Software description
HART ® identification codes and revision numbers
Manufacturer ID: 0x45
Device: 0xD0
Device Revision: 1
DD Revision 1
HART ® Universal Revision:
6
FC 375/475 system SW.Rev.: ≥ 2.0
AMS version: ≥ 7.0
PDM version: ≥ 6.0
FDT version: 1.2