Daewoo DWF-4230 Series Service Manual page 13

LOAD DRIVE UNIT
(CW WASH, CCW WASH, DRAINAGE, PUMP, HOT WATER, COLD WATER)
1) CIRCUIT DIAGRAM AND EXPLANATION
• Controlling load of button input in MICOM terminal, it is selected to 'L' or 'H'. It is selected to 'H' in running load case and in
'L' case, load driving is finished. In clockwise rotation of washing motor, as MICOM No. 23 is changed 6V to 0V, IC2
(TD62004AP) is turn on. And then, the TRAC1 (SM12JZ47) is turn on, the source of electric power is supplied to washing
motor for clockwise rotation. The TRIAC, as switching element, force to 'ON' or 'OFF' by use of the IC2 (TD62004AP). In
the rest roads, when the MICOM terminal voltage changes 6V to 0V, each DRIVE IC is active, and then the TRIAC
switches the source of electric power to loads.
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2) DETAIL EXPLANATION OF CIRCUIT ACTION (ACTION OF CW WASH)
• In case MICOM TERMINAL No. 23 is 'H', the IC2 turn on and control the TRIAC. The resistance, as 100Ω & 1/2W, of the
r46 is used to limit the GATE current of the TRIAC.
• The ceramic condenser C22 between the T1 and the GATE of the TRIAC is used for preventing the wrong action by means
of the noise.
• The R56 (100Ω, 1W) and C21 (683K) between the T1 and T2 of the TRIAC is used for protecting the TRIAC, it is usually
called SNUBBER CIRCUIT.
• The waveform of MICOM pin No. 23
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