2-7
EN
Burst mode is compatible with use of the analog signal. Because HART
®
protocol
features simultaneous digital and analog data transmission, the analog value can
drive other equipment in the loop while the control system is receiving the digital
information. Burst mode applies only to the transmission of dynamic data (pressure
and temperature in engineering units, pressure in percent of range, and/or analog
output in mA or V), and does not affect the way other transmitter data is accessed.
Access to information other than dynamic transmitter data is obtained through the
normal poll/response method of HART communication. A HART-based
communicator or the control system may request any of the information that is
normally available while the transmitter is in burst mode. Between each message
sent by the transmitter, a short pause allows the HART-based communicator or a
control system to initiate a request. The transmitter will receive the request, process
the response message, and then continue “bursting” the data approximately three
times per second.
Save, Recall, or Clone Configuration Data
Data that was entered off-line can be stored in the communicator memory and
downloaded to other transmitters later. Data also can be copied from a transmitter in
order to be sent to other transmitters in a process known as “cloning”. This is
especially useful if you work with a large number of transmitters that require the
same configuration data.
Enable or Disable Local Span and Zero Buttons
The
Local Keys
command allows you to enable or disable the local span and zero
buttons. Disabling the local keys will prevent unauthorized reranging using the span
and zero buttons, but will not prevent reranging using the communicator. To prevent
all changes to the configuration data, use the transmitter security jumper (see
“Transmitter Security” on page 4-12).
HART Fast Keys
left arrow, 3 (note)
HART Fast Keys
1, 4, 4, 1, 7
4690.bk : 4690.s2 Page 7 Tuesday, May 26, 1998 5:28 PM
