Rockwell Automation Reliance Electric MD65, Руководство пользователя

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PID Set Up
I-3
• As tension increases or decreases during winding, the Speed
Reference is trimmed to compensate. Tension is maintained
near the Equilibrium set point.
PID Reference and Feedback
PID Ref Sel (A132) is used to enable the PID mode (A132 does not
equal 0; “PID Disabled”) and to select the source of the PID
Reference. If PID Ref Sel (A132) is not set to 0 “PID Disabled”, PID
can still be disabled by select programmable digital input options
(parameters A051-A054) such as “Jog”, “Local” or “PID Disable”.
Table I.1 – PID Ref Sel (A132) Options
Speed Reference
0 Volts
PID Feedback =
Dancer Pot Signal
10 Volts
PID Reference =
Equilibrium Set Point
Option Description
0 “PID Disabled” Disables the PID loop (default setting)
1 “PID Setpoint“ Selects Exclusive Control. A137 [PID Setpoint] will be used to set the value of
the PID Reference
2 “0-10V Input” Selects Exclusive Control. Selects the 0-10V Input. Note that the PID will not
function with a bipolar analog input. It will ignore any negative voltages and treat
them like a zero.
3 “4-20mA Input” Selects Exclusive Control. Selects the 4-20mA Input.
4 “Comm Port” Selects Exclusive Control. The reference word from a communication network
such as Modbus RTU or DeviceNet becomes the PID Reference. The value
sent over the network is scaled so that P035 [Maximum Freq] x 10 = 100%
reference. For example, with [Maximum Freq] = 60 Hz, a value of 600 sent over
the network would represent 100% reference.
5 “Setpnt, Trim” Selects Trim Control. A137 [PID Setpoint] will be used to set the value of the
PID Reference.
6 “0-10V, Trim” Selects Trim Control. Selects the 0-10V Input. Note that the PID will not function
with a bipolar analog input. It will ignore any negative voltages and treat them
like a zero.
7 “4-20mA, Trim” Selects Trim Control. Selects the 4-20mA Input.
8 “Comm, Trim” Selects Trim Control. The reference word from a communication network such
as Modbus RTU or DeviceNet becomes the PID Reference. The value sent over
the network is scaled so that P035 [Maximum Freq] x 10 = 100% reference. For
example, with [Maximum Freq] = 60 Hz, a value of 600 sent over the network
would represent 100% reference.