M-Maxâ„¢ Series Adjustable Frequency Drive - Eaton Corporation

PID Controller (P9)
The M-Max series frequency inverters are provided with a
PID controller that you activate with P9.1 = 1. The controller
can be deactivated via a digital input (P3.12).
PID control is superimposed on the frequency inverter
function. You should therefore set all of the frequency
inverter’s drive-related parameters, such as maximum output
frequency (motor speed), acceleration and deceleration
ramps (mechanical load, belts). Frequency inverter and motor
are process-integrated actuators. The output frequency to
the motor (which determines the speed) is specified as
manipulated variable from the PID controller.
PID Controller
PNU ID
Access
RUN Value/Range Description
Parameters
When the PID controller is activated, the setpoints and actual
values become process variables and are normalized
automatically into percentages (%). For example, the
specified setpoint (0–100%) here is the same as a volume
flow (0–50 m3 /h). The actual value here is the volume flow
(m3 /h) from a suitable sensor, which is evaluated again as a
percentage (0–100%).
If this process data is to be displayed in the physical variable
(m3 /h), you can set the conversion with parameter P9.19
(see “Display factor (P9.19)”).
P9.1 163 — PID Controller 0
0 Deactivated
1 Activated for drive control
2 Activated for external application
P9.2 118 — PID controllers, P gain 100
0–1000% Proportional Gain (KP)
Low values attenuate the control action
High values can cause oscillation
P9.3 119 — PID controller, I reset time 10.0
0–320s Integral time constant
P9.4 167 — PID controller, keypad reference 0.0
0–100% Setting range
P9.5 332 — PI controller, setpoint source 0
0 The setting range is limited by P6.3 (raised starting frequency)
and P6.4 (end frequency)
Keypad (P9.4)
1 Fieldbus
2 AI1
3 AI2
Factory Setting
(P1.3)
M-Max Series Adjustable Frequency Drive MN04020003E—April 2011 www.eaton.com 93