WEG CFW501 V1.8X, Programming Manual, Page: 166 / 192

HVAC Functions
18-8 | CFW501
18
P1051 – Filter Maintenance Alarm Time
Adjustable
Range:
0 to 32000 h Factory
Setting:
5000 h
Properties:
Access groups
via HMI:
HVAC
Description:
This parameter defines the operation time of motor driven by CFW501 frequency inverter needed to be done
changing the filter system. This value is compared with the operation time (P1052) to be generated the alarm
(A0770) or fault (F0771) due to filter maintenance.
P1052 – Operation Time for Filter Maintenance Alarm
Adjustable
Range:
0 to 32000 h Factory
Setting:
Properties:
Access groups
via HMI:
HVAC
Description:
This parameter indicates the operation time of motor driven by CFW501 frequency inverter.
NOTE!
Set P1050 in “0” to reset the operation time for filter maintenance alarm.
18.6 MAIN PID CONTROLLER
This parameter group allows the user to configure the Main PID controller operation.
The control of the motor speed driven by CFW501 frequency inverter is done by comparing the process variable
control (feedback) with the required automatic setpoint.
The Main PID controller will be marked out to operate from 0.0 to 100.0 %, which 0.0 % equates to minimum
speed programmed in P0133 and 100.0 % equals maximum speed programmed in P0134.
The process variable control is that the Main PID controller takes as return (feedback) of its control action being
compared with the setpoint required to generate the control error.
The same is read via an analog input, so you will need to configure which of the analog inputs serve as feedback
for the Main PID controller.
Is adopted the "Academic" structure for the Main PID controller, which obeys the following equation:
u(k) = u(K-1) + Kp ∙ [(1 + Ki ∙ Ts + (Kd/Ts)) ∙ e(k) - (Kd/Ts)) ∙ e(k-1)]
where:
u(k) = Main PID controller output;
u(K-1) = Output in the last instant;
Kp = Proportional gain;
Ki = Integral gain;
Kd = Derivative gain;
Ts = Sampling time;
e(k) = Error in the actual instant (setpoint – feedback);
e(k-1) = Error in the last instant.