User manual OMRON SYSMAC CS REFERENCE MANUAL 01-2008

[. . . ] SYSMAC CJ Series SYSMAC One NSJ Series Programmable Controllers INSTRUCTIONS REFERENCE MANUAL SYSMAC CS Series CS1G/H-CPU SYSMAC One NSJ Series Programmable Controllers Instructions Reference Manual Revised January 2008 iv Notice: OMRON products are manufactured for use according to proper procedures by a qualified operator and only for the purposes described in this manual. The following conventions are used to indicate and classify precautions in this manual. Failure to heed precautions can result in injury to people or damage to property. !DANGER !WARNING Indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury. [. . . ] The Greater Than Flag turns ON if the manipulated variable after the PID action exceeds the upper limit. The Less Than Flag turns ON if the manipulated variable after the PID action is below the lower limit. Within the PID parameters (C to C+38), the only value that can be changed while the input condition is ON is the set value for C. If any other value is changed, be sure to turn the input condition from OFF to ON to enable the new value. Example At the rising edge of CIO 000000 (OFF to ON), the work area in D00209 to D00238 is initialized according to the parameters (shown below) set in D00200 to D00208. After the work area has been initialized, PID control is executed and the manipulated variable is output to CIO 0020. When CIO 000000 is turned ON, PID control is executed at the sampling period intervals according to the parameters set in D00200 to D00208. The PID constants used in PID calculations will not be changed if the proportional band (P), integral constant (Tik), or derivative constant is changed after CIP 000000 turns ON. 761 Data Control Instructions Section 3-18 C: D00200 C+1: D00201 C+2: D00202 C+3: D00203 Parameters C+4: D00204 C+5: D00205 C+6: D00206 PV: word 0010 C+7: D00207 PID control 012C 0064 04B0 0190 0032 0000 0494 Set value: 300 Proportional band: 10. 0% Integral time: 120. 0 s Derivative time: 40. 0 s Sampling period: 0. 5 s Reverse operation (bit 00: 0), PID constant updating timing = input condition is ON (bit 01: 0), Manipulated variable output designation: 0% (bit 03: 0), 2-PID parameter = 0. 65 (bits 04 to 15: 000 hex) Manipulated variable output range: 12 bits (bits 00 to 03: 4 hex), Integral/derivative constants: time designation (bits 04 to 07: 9 hex), Input range: 12 bits (bits 08 to 11: 4 hex), Manipulated variable limit control: No (bits 12: 0 hex), PID starting integral manipulated variable designation = start from same integral manipulated value as manipulated variable output designation (bit 14: 0 and bit 13: 0) 0000 C+8: D00208 0000 C+9: D00209 Work Area to C+38: D00238 Manipulated variable output: CIO 0020 Note When CIO 000000 is OFF, operation can be the same as manual operation by writing to CIO 0020. When changing from manual operation to automatic operation by executing PID(190), extreme changes in the manipulated value are restricted. (The manipulated variable after switching to automatic operation will start at the previous value of the integral manipulated variable. ) Input Values and Manipulated Variable Ranges The number of valid input data bits for the measured value is designated by the input range setting in C+6, bits 08 to 11, and the number of valid output data bits for the manipulated variable output is designated by the output range setting in C+6, bits 0 to 3. These ranges are shown in the following table. C+6, bits 08 to 11 or Number of valid bits C+6, bits 00 to 03 0 1 2 3 4 5 6 7 8 8 9 10 11 12 13 14 15 16 Range 0000 to 00FF hex 0000 to 01FF hex 0000 to 03FF hex 0000 to 07FF hex 0000 to 0FFF hex 0000 to 1FFF hex 0000 to 3FFF hex 0000 to 7FFF hex 0000 to FFFF hex If the range of data handled by an Analog Input Unit or Analog Output Unit cannot be set accurately by setting the number of valid bits, APR(069) (ARITHMETIC PROCESS) can be used to convert to the proper ranges before and after PID(190). The following program section shows an example for a DRT1-AD04 Analog Input Unit and DRT1-DA02 Analog Output Unit operating as DeviceNet slaves. The data ranges for these two Units is 0000 to 1770 hex, which cannot be specified merely by setting the valid number of digits. APR(069) is thus used to convert the 0000 to 1770 hex range of the Analog Input Unit to 0000 762 Data Control Instructions Section 3-18 to FFFF hex for input to PID(190) and then the manipulated variable output from PID(190) is converted back to the range 0000 to 1770 hex, again using APR(069), for output from the Analog Output Unit. Execution condition From Analog Input Unit Control Data C (D01000): C+1 (D01001): C+2 (D01002): C+3 (D01003): C+4 (D01004): ARP D01000 Analog input value D02000 0000 Hex (binary with one table) 1770 Hex (Xm) 0000 Hex (Yo) 1770 Hex (X1) FFFF Hex (Y1) PID D02000 D02500 D03000 Control Data C+6 (D02506): @8@8 Valid number of bits: 16 (0000 to FFFF Hex) Valid number of bits: 16 (0000 to FFFF Hex) Control Data C (D01500): C+1 (D01501): C+2 (D01502): C+3 (D01503): C+4 (D01504): 0000 Hex (binary with one table) FFFF Hex (Xm) 0000 Hex (Yo) FFFF Hex (X1) 1770 Hex (Y1) ARP D01500 D03000 Analog output value To Analog Output Unit Performance Specifications Item PID control method Number of PID control loops Sampling period PID constant Proportional band Integral constant Derivative constant Set value Measured value Manipulated variable ---- P Tik Tdk SV PV MV Specifications Target value filter-type two-degrees-of-freedom PID method (forward/ reverse) Unlimited (1 loop per instruction) 0. 01 to 99. 99 s 0. 1 to 999. 9% 1 to 8191, 9999 (No integral action for sampling period multiple, 9999. ) 0 to 8191 (No derivative action for sampling period multiple, 0. ) 0 to 65535 (Valid up to maximum value of input range. ) 0 to 65535 (Valid up to maximum value of input range. ) 0 to 65535 (Valid up to maximum value of output range. ) Calculation Method Calculations in PID control are performed by the target value filtered control with two degrees of freedom. Block Diagram for Target Value PID with Two Degrees of Freedom When overshooting is prevented with simple PID control, stabilization of disturbances is slowed (1). If stabilization of disturbances is speeded up, on the other hand, overshooting occurs and response toward the target value is slowed (2). When target-value PID control with two degrees of freedom is used, on the other hand, there is no overshooting, and response toward the target value and stabilization of disturbances can both be speeded up (3). Target value filter Set value (target value) 1 + (1 ­ ) Ti · s 1 + Ti · s + ­ Proportional + integral elements Kp + Kp Ti · s + ­ Kp: Proportional constant Ti: Integral time Td: Derivative time s: Laplace operator : 2-PID parameter : Incomplete derivative coefficient Manipulated variable Preceding derivativetype elements Measured value (PV) Kp Td/s 1 + . Td · s 763 Data Control Instructions Simple PID Control (1) (3) Section 3-18 Feed-forward PID Control As the target response is slowed, the disturbance response worsens. (2) Target response Disturbance response Overshoot As the disturbance response is slowed, the target response worsens. PID Parameter Settings Control data C Item Contents Setting range Change with ON input condition Allowed Set value (SV) C+1 Proportional band C+2 Tik Integral Constant Binary data (of the same number of bits as specified for the input range) The parameter for P action 0001 to 270F hex (1 to 9999); expressing the proportional con- (0. 1% to 999. 9%, in units of trol range/total control range. 0. 1%) A constant expressing the 0001 to 1FFF hex (1 to 8191); strength of the integral action. As (9999 = Integral operation not this value increases, the integral executed) (See note 1. ) strength decreases. 0001 to 1FFF hex (1 to 8191); (0000 = Derivative operation not executed) (See note 1. ) The target value of the process being controlled. Can be changed with input condition ON if bit 1 of C+5 is 1. C+3 Tdk Derivative Constant 0001 to 270F hex (1 to 9999); Not allowed (0. 01 to 99. 99 s, in units of 10 ms) Bits 04 to 15 2-PID parameter () The input filter coefficient. Nor000 hex: = 0. 65 of C+5 mally use 0. 65 (i. e. , a setting of Setting from 100 to 163 hex 000). The filter efficiency means that the value of the rightdecreases as the coefficient most two digits is set from = approaches 0. [. . . ] (Extensive changes too numerous to list. ) New timer and counter instructions added: TIMX, TIMHX, TMHHX, TTIMX, TIMLX, MTIMX, CNTX, CNTRX, and CNRX. "PC" changed globally to "PLC" when the meaning is Programmable Controller. Pages 787, 814, 816 to 832: Information added on automatic port allocation. Pages xiv to xviii: Application Precautions replaced with same section from Programming Manual. [. . . ]