Hart Variables - Siemens SIMATIC ET 200SP HA Equipment Manual

HART function
7.4 Tags
The HART variables are assigned to a channel in the properties dialog of the module. The HART
variables are configured via parameter data record 130. This allows you to process measured
values directly from the field device as input data in the automation device.
Parameter assignment and structure of the HART mapping parameters (Page 62)
You also determine the use of the multiHART range and its properties in the properties dialog box
of the I/O module.
multiHART range (Page 49)
Address assignment
You can choose to configure the following:
• Maximum 4 HART variables
Each HART variable occupies 5 bytes of input data. As soon as you configure (map) at least
one HART variable in the input address space, the addresses for all 4 tags are assigned (20
bytes).
• A multiHART range
If the multiHART range is used, an additional 4 bytes of input address space and 1 byte of
output address space is allocated.
7.4.2

HART variables

Definition
Each HART variable consists of a 4-byte real value and one byte of quality code. A maximum of
four HART variables supported by the connected field device are read cyclically for each channel
with enabled HART functionality. The HART variables are read automatically via the HART
command 3 (for field devices with HART Rev. 5 and 6) or via command 9 (for field devices with
HART Rev. 7 or later).
These four HART variables are always stored in the HART variable data record 121 for each
channel and can be read at any time.
HART variable data record (Page 81)
Description
The following HART variables are available:
• PV (Primary Variable)
• SV (Secondary Variable)
• TV (Tertiary Variable)
• QV (Quaternary Variable)
46
AI 4xI 2-/4-wire HART ISOL HA
Equipment Manual, 07/2022, A5E50101523-AB