Reading The Detected Temperature Value Of The Module (Single Type); (G3F-Rd3A : Rtd3Rd, G4Frd2A : Rtd2Rd) - LG GLOFA G3F - RD3A User Manual

Chapter 4. FUNCTION BLOCKS

4.2.3 Reading the Detected Temperature Value of the Module (Single Type)

(G3F-RD3A : RTD3RD, G4FRD2A : RTD2RD)

The stand-alone type Temperature conversion value reading function block processes o nly one channel
of the RTD input module. If a channel is enabled then the function block outputs the detected
temperature value and its digital conversion value that is usable as a PV in the PID control module.
Function
I/O Variable
Block
I REQ
BASE
SLOT
CH
O DONE
STAT
ALM
TEMP
SCAL
Data
Type
BOOL Function block execution request area
- Used to request an execution of the reading function block
- If the conditions connected with this area are established while the
program is running and "0" changes into "1", the reading function block
is executed.
USINT Base location No.
- Used to write the number of the base where the RTD input module is
loaded.
- Setting range: GM1 series(0~31), GM2 series(0~7), GM3/4 series(0-3)
USINT Slot location No.
- Used to write the number of the slot where the RTD input module is
loaded.
- Setting range: 0~7
USINT Area for specifying the used channel.
Settings : G3F -RD3A: 0 to 7, G4F-RD2A: 0 to 3
BOOL Function block execution complete status
- "1" is output when the reading function block is finished with no error and
"1 " remains until next execution. If an error occur, '0' is displayed and the
operation enters into the stop state.
USINT Error status indication area
- Used to output the number of an error when it occurs during reading
function block execution.
- For description of errors, see GM Section 7.4
BOOL Run channel error indication area
- "1" is output if error occurs for each run channel.
IN T Detected temperature value output area
- The CPU module reads the detected temperature value(-200.0°C to
+600.0°C) of the corresponding channel from the RTD input module and
outputs it to this area.
- The detected temperature value of each channel is 10 times than the real
temperature value.
(Example: Detected temperature value 1234 → real temperature value
123.4°C)
INT Digital conversion value output area
- The CPU module reads the digital conversion of the corresponding
channel from the RTD input module and outputs it to this area.
- The detected temperature value (-200.0°C to +600.0°C) of each channel
is converted into a digital value within 0 to 16000 and i t is output to this
area.
- Value to be read from the output variable.
• SCAL =(the value to be read from the output variable TEMP + 2000)
5 2
• Example: Where a temperature is 234.5°C.
The value to be read from the TEMP is (temperature 5 10),
then
2345 is the detected temperature value.
The value to be read from the SCAL is (2345 + 2000) 5 2,
i.e., 8690.
- The output value converted into a digital value can be used as the PV of
the PID control module.
4 - 4
Descriptions