Hitachi RAF-25NH4 Données Techniques page 197

4. P.W.B Power Supply Circuit (Switching Power Circuit)
Ｔ Ｅ Ｒ Ｍ Ｉ Ｎ Ａ Ｌ
Ｂ Ｏ Ａ Ｒ Ｄ
２ ５ Ａ Ｆ Ｕ Ｓ Ｅ
Ｌ
Ｂ Ｌ Ｋ
ＶＡ Ｒ Ｉ Ｓ Ｔ Ｏ Ｒ １
ＳＵＲＧ Ｅ ＡＢＳＯＲＢ Ｅ Ｒ
ＷＨ Ｔ
Ｎ
Ｇ Ｒ Ｎ ３
Cautions!
If it miss connections,
protection will work and
35V will not be outputted.
Indoor unit 1
Indoor unit 2
Indoor unit 3
Indoor unit 4
Terminal board
RAM-70QH4 and RAM-80QH4 have [
charge of outdoor control power supply entirely) on their control P.W.B. RAM-70QH4 and RAM-80QH4 have [SWITCHING POWER
SUPPLY CIRCUIT FOR INDOOR UNIT] (the circuit generates 35V power supply for the indoor units of 4 rooms (3 rooms in case of 3
rooms multi) and 12V, 5V, for electric expansion valve control on their SW-D- P.W.B. with 2-circuit.)
The functions of switching power circuit, input DC approx. 325V, which was rectificated by the diode bridge DB1, into the primary.
Switch the control IC on and off at high speed to generate the voltage in the switching transformer primary winding. Transmit the
voltage to the secondary winding through the transformer core. The voltage is generated at each secondary output corresponding to
each winding.
Ｂ Ｌ Ｕ
Ｙ Ｅ Ｌ
（Ｓ Ｐ Ｉ Ｒ Ａ Ｌ）
（Ｓ Ｐ Ｉ Ｒ Ａ Ｌ）
Ｎ Ｏ Ｉ Ｓ Ｅ
Ｆ Ｉ Ｌ Ｔ Ｅ Ｒ Ｃ Ｏ Ｉ Ｌ １
ＶＡＲ Ｉ ＳＴＯＲ２
Ｖ Ａ Ｒ Ｉ Ｓ Ｔ Ｏ Ｒ ３
Ｌ ０ ０ １
Diode bridge １
SW power supply for outdoor
control P.W.B.
12V-A, 12V-B, 5V-A, 5V-B
17V-A, 17V-B, -5V
Ｃ １
The I/F circuit for unit 1
Ｄ １
Ｃ ２
The I/F circuit for unit 2
Ｄ ２
Ｃ ３
The I/F circuit for unit 3
Ｄ ３
Ｃ ４
The I/F circuit for unit 4
Ｄ ４
Fig. 4-1 Function of P.W.B. Power Supply Circuit
WITCHING POWER UPPLY CIRCUIT FOR OUTDOOR CONTROL P.W.B.
Ｒ Ｅ Ａ Ｃ Ｔ Ｏ Ｒ Ｃ
Ｂ Ｌ Ｕ
Ｙ Ｅ Ｌ
Ｐ ＯＷ Ｅ Ｒ Ｒ Ｅ Ｌ Ａ Ｙ Ａ
Ｒ ０ ０ ２
Ｉ Ｎ Ｒ Ｕ Ｓ Ｈ
Ｐ Ｒ Ｅ Ｖ Ｅ Ｎ Ｔ Ｉ Ｏ Ｎ
Ｒ Ｅ Ｌ Ａ Ｙ Ａ
Ｃ Ｔ −Ａ
Ｌ ０ ０ ４
Ｐ ＯＷ Ｅ Ｒ Ｒ Ｅ Ｌ Ａ Ｙ Ｂ
Ｒ ０ ０ ３ Ｉ Ｎ Ｒ Ｕ Ｓ Ｈ
Ｐ Ｒ Ｅ Ｖ Ｅ Ｎ Ｔ Ｉ Ｏ Ｎ
Ｒ ０ ０ ４
Ｒ Ｅ Ｌ Ａ Ｙ Ｂ
Ｌ ０ ０ ６
Ｌ ０ ０ ５
Ｃ Ｔ −Ｂ
＋
216
ＳＷ−Ｄ P.W.B.
＋
３ Ａ- Ｆ Ｕ Ｓ Ｅ
Ｃ ２ ０ １
SW power supply
for unit 3 & unit 4.
(35V-B BEN5V-B)
(BEN12V-B)
SW power supply
for unit 1 & unit 2.
(35V-A BEN5V-A)
(BEN12V-A)
] (the circuit is in