WT-W7111TH - LG Washing Machine Service Manual (repair manual). Page 8

This is electric braking system controlled by electric current of opposite direction of motor’s.

The principle of drain-start is that the counter clockwise revolving of drain motor cam to the position 
marked below figure. enable the plunger valve rod (PV rod) to be pulled so that the bellows could be open
to make a drainage.
The principle of drain-stop is that the same direction revolving of drain motor cam to the initial position
enables the plunger valve rod to return back so that the bellows could be closed to make a drain-stop.

<The structure of Drain Motor>

<Circuit of Drain Motor>

<Drive Asm>

Capacitor

IPM

Drain Motor

PV Rod

Bellows

Revolving
Cam

A

3

1

2

1

2

3

PV Case

S/W

Characteristics

● 

When the power on, the drain motor cam revolve only counter clockwise. 

●

In case of revolving the cam by manual when the power off, we designed the cam to rotate one direction, not
counter clockwise but counter clockwise.

● 

The function of internal switch of drain motor is that sensing the initial position of the drain motor cam. So the
power should be always off at the position of drain-stop .

● 

If you push the start/pause button or the power button during drain, the drain motor cam returns to the initial
point finally to stop the drain. But if you pull the power cord from outlet or being the stoppage of electric during
drain, the drain goes ahead. At the moment of power on again, the drain motor cam returns to the initial point.

● 

For the compulsory drain the drain motor cam should be revolved to the point " " counter clockwise by
manual.