IDEC MicroSmart Pentra - Manual (Page 47)

D EVICE A LLOCATION OF PID M ODULE
5-6 FC5A MicroS mart PID Module User’s Manual FC9Y-B1283
Example 3: Changing Block 4 Parameter
The PV filter time constant (D1063) of CH0 is changed to 1.5 seconds. In this example, D1000 is allocated
to the control register and M500 is allocated to control relay.
The parameter can be changed with the following procedure.
1. Turn on M500 (Reading all parameters). All PID module parameters are read out from the PID module
and stored in the data registers of the CPU module.
*1
2. Turn off D1022.0 (Control enable bit of CH0). CH0 control of the PID module will be disabled.
3. Store 15 in D1063 (PV filter time constant of CH0).
*2
4. Turn on M505 (Block 4 writing).
*3
5. Turn on D1022.0 (Control enable bit of CH0). CH0 of the PID module will be enabled.
Ladder Program Example:
*1: If the reading all parameters (M500) is turned on, all PID module parameters are read out from the PID module and
stored in the data registers. Block 4 parameters are stored in D1053 to D1102.
*2: For a value with a decimal point, store the value multiplied by 10 in the data register.
*3: Block 4 parameters stored in D1053 to D1102 are written to the PID module. The parameters of the other blocks
are not written.
Note: If parameters of block 4 or 5 are changed while CH0 or CH1 control is enabled in the PID module, an unexpected
operation of the PID module may be caused. It is recommended that the control channel of the PID module be disabled
before changing the parameters of block 4 or 5.
3rd Scan
At the rising edge of M102, D1022.0 is turned on to
enable CH0 control.
M102 is turned off.
1st Scan
At the rising edge of M101, D1022.0 is turned off to
disable CH0 control.
M500 is turned on to read all parameters from the
PID module.
M101 is turned off.
2nd Scan
At the falling edge of M101, M500 is turned off.
15 is stored in D1063 (PV filter time constant of CH0).
M505 (Block 4 writing) is turned on to write block 4
parameters stored in D1053 to D1102 to the PID
module.
M102 is turned on.