WEG CFW-11 Series, Programming Manual

Page: 280 / 307

PID Regulator [46]
20-8
20
20.3 SLEEP MODE
The sleep mode is a useful resource for saving energy when using the PID regulator. Refer to the Figure 20.2
on page 20-4 .
In many PID applications energy is wasted by keeping the motor turning at the minimum speed when, for
instance, the pressure or the tank level keeps increasing.
The sleep mode works together with the zero speed disable function.
In order to activate the sleep mode, enable the zero speed disable by programming P0217 = 1 (On). The
disable condition is the same as for the zero speed disable without PID. Refer to the
Section 12.6 ZERO SPEED
LOGIC [35] on page 12-10 .
However, the P0291 setting must be: P0133 < P0291 < P0134. Refer to the Figure 20.2 on page 20-4 .
In order to leave the sleep mode (wake-up), when in the automatic PID mode, besides the condition programmed
in P0218, it is necessary that the PID error (the difference between the setpoint and the process variable) be
greater than the value programmed in P0535.
DANGER!
While in the sleep mode, the motor may turn at any moment because of the process conditions.
If it is wished to handle the motor or to perform any type of maintenance, remove the power from
the inverter.
20.4 MONITORING MODE SCREENS
When the PID regulator is used, the monitoring mode screen can be configured to show the main variables in
a numerical form or as a bar graph, with the respective engineering units.
An example of the keypad (HMI) with that configuration can be seen in the
Figure 20.4 on page 20-8 , where
the process variable and the setpoint, both in BAR, and the motor speed in rpm are showed. Refer to the Chapter
5 PROGRAMMING BASIC INSTRUCTIONS on page 5-1 .
Run
LOC
90rpm
16:54 Menu
5.0 bar
5.0 bar
990 rpm
Run
LOC
90rpm
16:56 Menu
bar
bar
rpm
1 5%
5%
45%
Figure 20.4 - Example of the keypad (HMI) in the monitoring mode for the PID Regulator function