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9. COMPONENT TESTING INFORMATION

9-1. FILTER ASSEMBLY (LINE FILTER)

When Resistance (Ohm) checking the Component, be sure to turn the power off,
and do voltage discharge sufficiently.

Test Points

Result

WH (1) to RD (3)

WH (3) to RD (1)

0 

1

0 

1

(3)
(1)

WH1

(3)

(1)

RD1

9-2. DOOR LOCK SWITCH ASSEMBLY

AC
Common
terminal
of Valve

The Door Lock Switch Assembly consists of a Heating PTC, a Bimetal, a
Protection PTC, and a Solenoid. It locks the door during a wash cycle.

1. Operation for door closing

- After the system turns on, PTC heating starts up through terminal 2~4’s

authorizing the power on.

- After PTC heating starts up and before solenoid operation is driven,

force the system to the off position through CAM.

Door close

- Authorizing one impulse through terminal 3~4 (PTC & solenoid) will

make the door locked.

- Door lock is detected when switches in terminal 4~5 are set closed.

CAM rotation will forcibly clear off the connection. 
The maximum, allowable number of impulse authorizations is 2
Upon the third authorization of the impulse, 

the position of CAM goes back to the door-open position.

- Authorizing the impulse occurs in 4.5 seconds upon input for max

performance and two authorization processes are allowed at most.

Normal operation period of PTC heating: 1.5 - 5 seconds 
(Defects from the development process)

2. Operation for door opening

- With a temporary stop, door automatically opens by CAM rotations after

authorizing the impulse from the terminal 3 ~ 4 and the power turns off -
maximum of 3 times of the authorizing period 

- Upon the fourth authorization of the impulse, the position of CAM goes

back to the door-close position.

Test Points

(2) to (4)

(3) to (4)

(4) to (5)

(2) to (4)

Result

700-1500 

1

60-90 

1

Infinity

120 Vac

Remarks

At 77

°F 

(25

°C

)

At 77

°F 

(25

°C

)

Voltage Input

(2)

(3)

(4)

(5)

9-3. STATOR ASSEMBLY

The DD motor can be driven from stopped to maximum speed in infinite steps in
either direction. There are 36 poles on the stator; 12 permanent magnets spaced
around the rotor. There are no brushes to wear out. Unlike a more traditional
brushless motor, the rotor surrounds the stator rather than being attached to it. 

Test Points

Result

(1) to (2)

(2) to (3)

(3) to (1)

5-15 

1

5-15 

1

5-15 

1