IDEC FC4A-C10R2, User Manual

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21: PID I
NSTRUCTION
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S1+16 Output Manipulated Variable Upper Limit
The value contained in the data register designated by S1+16 specifies the upper limit of the output manipulated variable
(S1+1) in two ways: direct and proportional.
S1+16 Value 0 through 100
When S1+16 contains a value 0 through 100, the value directly determines the upper limit of the output manipulated vari-
able (S1+1). If the manipulated variable (D1) is greater than or equal to the upper limit value (S1+16), the upper limit
value is outputted to the output manipulated variable (S1+1). Set a required value of 0 through 100 for the output manipu-
lated variable upper limit to the data register designated by S1+16. When S1+16 stores a value larger than 100 (except
10001 through 10099), the output manipulated variable upper limit (S1+16) is set to 100. The output manipulated variable
upper limit (S1+16) must be larger than the output manipulated variable lower limit (S1+17).
To enable the manipulated variable upper limit, turn on the output manipulated variable limit enable control relay (S2+2).
When S2+2 is turned off, the output manipulated variable upper limit (S1+16) has no effect.
S1+16 Value 10001 through 10099 (disables Output Manipulated Variable Lower Limit S1+17)
When S1+16 contains a value 10001 through 10099, the value minus 10000 determines the ratio of the output manipulated
variable (S1+1) in proportion to the manipulated variable (D1) of 0 through 100. The output manipulated variable (S1+1)
can be calculated by the following equation:
Output manipulated variable (S1+1) = Manipulated variable (D1)
×
(N – 10000)
where N is the value stored in the output manipulated variable upper limit (S1+16), 10001 through 10099.
If the manipulated variable (D1) is greater than or equal to 100, 100 multiplied by (N – 10000) is outputted to the output
manipulated variable (S1+1). If D1 is less than or equal to 0, 0 is outputted to S1+1.
To enable the manipulated variable upper limit, turn on the output manipulated variable limit enable control relay (S2+2).
When S2+2 is turned off, the output manipulated variable upper limit (S1+16) has no effect.
When S1+16 is set to a value 10001 through 10099, the output manipulated variable lower limit (S1+17) is disabled.
S1+17 Output Manipulated Variable Lower Limit
The value contained in the data register designated by S1+17 specifies the lower limit of the output manipulated variable
(S1+1). Set a required value of 0 through 100 for the output manipulated variable lower limit to the data register desig-
nated by S1+17. When S1+17 stores a value larger than 100, the output manipulated variable lower limit is set to 100. The
output manipulated variable lower limit (S1+17) must be smaller than the output manipulated variable upper limit
(S1+16).
To enable the output manipulated variable lower limit, turn on the output manipulated variable limit enable control relay
(S2+2), and set the output manipulated variable upper limit (S1+16) to a value other than 10001 through 10099. When the
manipulated variable (D1) is smaller than or equal to the specified lower limit, the lower limit value is outputted to the out-
put manipulated variable (S1+1).
When the output manipulated variable limit enable control relay (S2+2) is turned off, the output manipulated variable
lower limit (S1+17) has no effect.
S1+18 Manual Mode Output Manipulated Variable
The manual mode output manipulated variable specifies the output manipulated variable (0 through 100) for manual mode.
Set a required value of 0 through 100 for the manual mode output manipulated variable to the data register designated by
S1+18. When S1+18 stores a value larger than 100, the manual mode output manipulated variable is set to 100.
To enable the manual mode, turn on the auto/manual mode control relay (S2+1). While in manual mode, the PID action is
disabled. The specified value of the manual mode output manipulated variable (S1+18) is outputted to the output manipu-
lated variable (S1+1), and the control output (S2+6) is turned on and off according to the control period (S1+13) and the
manual mode output manipulated variable (S1+18).
S1+19 AT Sampling Period
The AT sampling period determines the interval of sampling during auto tuning. When using auto tuning, set a required
value of 1 through 10000 to specify an AT sampling period of 0.01 sec through 100.00 sec to the data register designated
by S1+19. When S1+19 stores 0, the AT sampling period is set to 0.01 sec. When S1+19 stores a value larger than 10000,
the AT sampling period is set to 100.00 sec.