Precision Digital Corporation Trident PD765, Инструкция по эксплуатации

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Trident Series PD765 Process & Temperature Meters
Instruction Manual
29
Scaling the 4-20 mA Analog Output
(
Aout
)
The 4-20 mA analog output can be scaled to provide
a 4-20 mA signal for any display range selected.
No equipment is needed to scale the analog output;
simply program the display values to the
corresponding mA output signal.
The
Analog Output
menu appears in the
Setup
menu
only on meters that are equipped with a 4-20 mA
output. This menu is enabled or disabled at the
factory via the Advanced Features menu. For more
information on the
Advanced Features Menu
see
page 30 .
The
Analog Output
menu is used to program:
1. 4-20 mA output based on display values
2. Sensor break value in mA
For instructions on how to program numeric
values see
Setting Numeric Values
, page
21
.
Isolated 4-20 mA Signal Splitters &
Converters
Precision Digital offers DIN rail mountable signal split-
ters and converters to spit the optional 4-20 mA signal
into two isolated 4-20 mA signals or into a 0-10 VDC
signal.
For more information see page 18 .
Program the Sensor Break Output
Value (
SEbr
)
The sensor break value corresponds to the output
signal generated when the meter detects a sensor
break for thermocouple and RTD inputs.
For example if there is an open thermocouple, the
meter displays the message “
open
” and the analog
output goes to the programmed sensor break value
(e.g. 3.00 mA).
The sensor break value can be programmed from
0.00 to 23.99.
The typical output signal range is 1.00 to 23.00 mA
(e.g. If sensor break value is programmed to 0.00, the
actual output will not be greater than 1.00 mA).
Analog Output when Display is Out
of Range
The analog output reflects the display out of range
conditions as follows:
Input
Condition
Display Analog
Output
Underrange Flashing
-1999
3.00 mA
Overrange Flashing
9999
21.00 mA
Open TC or
RTD
Flashing
open
Sensor break
value