Varec 2920, Инструкция по установке и эксплуатации, Страница: 109 / 194

5 Display and Configuration Interface
Varec, Inc. 99
Command
Command This is the HART Master control command. Four
commands are valid:
• Search - This causes the HART Master to start looking
for devices connected to the HART Bus. This is the
first step in utilizing data from a HART device. Once a
a device has been found, it is remembered by the
2920 FTT until a Hard Reset is performed.
• Enable - This command enables Scanning on the
HART Bus.
• Suspend - This command temporarily suspends
scanning of the HART Bus. The scanning
automatically resumes after several minutes.
• Disable - This command disables scanning on the
HART Bus. This is the default setting for the Bus.
Config Params
Mode This parameter controls if the HART Master is the
Primary or Secondary Master. This parameter is for
future enhancements. The current setting is Primary
Master.
HARTMode This parameter enables or disables the HART Bus.
Max Busy Retries This parameter sets how many times the HART Master
will retry a data command if the HART devices has
responded with a busy response. The default is 2.
Max Other Retries - This parameter sets how many
times the HART Master will retry a data command if
communications fails. The default is 2.
Max Other Retry This parameter sets how many times the HART Master
retries a data command if communications fails. The
default is 2.
Interleave If connected, the FMR is considered a higher priority
HART device. The FMR is polled at a higher rate with
other HART devices interleaved. This parameter
determines how many other devices are interleaved
with the scanning of the FMR. The default is 1.
Fast Scan Max This parameter determines how many FMR commands
are executed each time an FMR is scanned at the higher
rate. The default is one.
Start Delay This is the delay between when the HART Bus powers up
and when the HART Master starts scanning devices. This
allows the HART devices to power up and stabilize
before the Master starts scanning. The parameter is in
milliseconds. The default value is 12000 (12 seconds).
Scan Delay This parameters determines how long the HART Master
waits after scanning all HART devices before starting
another round of scanning. The parameter is in
milliseconds. The default value is 1500 (1.5 seconds).
All Params Lists all Display, Commands, and Config Params in a list.