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4. Power Supply Circuit
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Fig. 4-1 shows the power circuit.
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There are two switching power supply in Power PWB.
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Switching power supply 1 is generating the secondary power for control circuits and DC35V indoor unit 1.
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Switching power supply 2 is generating the DC12V for expansion valve and DC35V for indoor unit 2 and 3.
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Switching power supply performs voltage conversion effectively by switching transistor IC1 to convert DC330V
to high frequency of approximately 20kHz to 200kHz.
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Transistor IC1 operates as follows:
Fig. 4-1 Power circuit for P.W.B.
Summary of Contents for RAM-55QH5
Page 31: ... 30 CAPACITY DIAGRAM RELATED TO THE PIPING LENGTH MODEL RAM 65QH5 ...
Page 37: ...CIRCUIT DIAGRAM MODEL RAM 55QH5 39 L C023 C022 C002 C001 C025 C024 N ...
Page 38: ...CIRCUIT DIAGRAM MODEL RAM 65QH5 41 L C023 C022 C002 C001 C025 C024 N ...
Page 41: ... 45 ...
Page 46: ... 51 Outdoortemperature STAROTP_C TSKTM1_C1 Outdoortemperature STAROTP_C TSKTM1_C2 ...
Page 47: ... 53 ...
Page 48: ... 55 ...
Page 49: ... 57 ...
Page 50: ... 59 ...
Page 68: ... 77 5A ...
Page 75: ... 84 ...
Page 76: ... 85 5 Reversing valve control circuit Fig 5 1 ...
Page 91: ... 103 ...
Page 92: ... 104 ...
Page 98: ... 110 TROUBLESHOOTING OF THE SYSTEM POWER MODULE ...
Page 99: ... 111 ...
Page 100: ... 112 ...
Page 102: ... 114 three three inlet 3 Cut off the three pipes at the side and bottom of Reversing valve ...
Page 103: ... 115 ELECTRIC EXPANSION VALVE PIPE THERMISTOR POSITION CHARTS MODEL RAM 55QH5 MODEL RAM 65QH5 ...
Page 108: ...HITACHI PM NO 0312E Printed in Malaysia RAM 55QH5 RAM 65QH5 ...