Chapter 4. FUNCTION BLOCKS
4 - 6
4.3.2
Reading the Detected Temperature Value of the Module
(G3F-RD3A : RTDR3RD, G4F-RD2A : RTDR2RD)
The module temperature conversion value reading function block specifies the location No. of the slot where the communication
module loaded in the receiving station, the station No. of the communication module loaded in the remote I/O station If also
processes all channels in block. The enabled channel outputs the temperature conversion value and its digital conversion value that
can be used as the PV in the PID control module, and the two values are used in the program.
Function
Block
I/O
Variable
Data
Type
Descriptions
REQ
BOOL
Function block execution request area (at the ascending edge)
- 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(rising edge)”, the module reading function block is executed.
NET_N
O
USINT
Location No. of the slot where the communication module of the station to which the
function block will be sent is loaded.
- Setting range: 0 ~ 7
ST-NO
USINT
Station No. of the communication module loaded in the remote I/O station.
-Setting range: 0 ~ 63
BASE
USINT
Base module location No.
- Used to write the number of the base where the RTD input module is loaded.
- Setting range: 0 ~ 3
SLOT
USINT
Slot location No.
- Used to write the number of the slot where the RTD input module is loaded.
- Setting range: 0~7
I
CH
BOOL
[Array]
*Note 1
Run channel enable/disable specification
- Used to enable or disable a channel for run.
- Specify “1” for enabling, and “0” for disabling
NDR
BOOL
“1” when the function block is finished without error. “1” remains during the scan where
the execution condition is being satisfied and changes into “0” at next scan.
ERR
BOOL
Error information indication area
- If error occurs during reading function block execution “1” is outputted and the module
enter into the stop state. “1” remains during the scan where the execution condition is
being satisfied and it changes into “0” at the next scan.
STAT
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
ACT
BOOL
[Array]
*Note 1
Run channel status indication area
- After the reading function block is finished with no error, “1” is output if the channel is in
normal state. But “0” is output for the disabled channels.
ALM
BOOL
[Array]
*Note 1
Run channel error indication area
- “1” is outputted when error occurs for each run channel.
ALM_
CODE
USINT
[Array]
*Note 1
Run channel error code area
- Used to output the code of error occurred during run for each channel.
- For error description, see GM Section 7.4.
TEMP
INT
[Array]
*Note 1
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)
O
SCAL
INT
[Array]
*Note 1
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 the a digital value within 0 to 16000 and it is outputted to this area.
- Value read from the output variable, SCAL = (the value read the output variable
TEMP + 2000)
5
2
•
Example: Where a temperature is 234.5
°
C.
The value read from the TEMP Is (temperature
5
10), then
2345 is the detected temperature value.
The value read form 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.
REMARK
Note 1: The numbers of Array are 8 in G3F-RD3A, 4 in G4F-RD2A.