– 84 –
Drive
signal
Chopper
signal
Chopper
signal
DC
Current
level
DC current
Detection
resistor
5V
DC 260V
-360V
Reset circuit
Over-load external
setting circuit
Current amplified
circuit
Drive
Circuit
IP signal
Reset Voltage
Peak current
cut off circuit
Outdoor microcomputer
Tr
ip signal
synthesis circuit
Compressor
motor
Power
module
Fig. 8-2
●
The following describes the operations of each circuit in detail.
(1) Peak current cut off circuit
Fig.8-3 Peak Current Cut off Circuit and Waveforms at Each Section.
DC current Id
Voltage at point
1.35V
27A
Voltage at point
A
B
A
–
Fig.8-3
Detection
resistor
Negative
Terminal
DC
current
0V
0V
R43
0V
R41
QC
R42
SPM2
SPM2 – HIC
Main P.W.B
HIC
IC1
CN14
IP
Outdoor
microcomputer
F
R43
9
9
8
20
9
2
39
17
B
●
The Ip cut off circuit detects an instantaneous excessive current and stops inverter to protect parts such
as SPM2, etc.
●
As shown in diagram, if current exceeding 27A flows, voltage at point recognized
by detecting resistor is input to pin of SPM2 – HIC, and voltage divided by R41 and R43 is input to pin
of IC1. Since threshold of IC1 is exceeded in this case, Lo signal is input from pin
(Voltage at point
. When Lo signal is input to pin of microcomputer, microcomputer stops drive output.
●
When drive output from microcomputer is stopped, all drive output goes Hi, and microcomputer is initialized
to enter drive signal standby mode. 3 minutes later, microcomputer outputs drive signal again, to start
operation.
10
8
9
B
A
17
Содержание RAC-50YH4
Страница 37: ... 9 MODEL RAS 50YH4 CIRCUIT DIAGRAM ...
Страница 38: ...CIRCUIT DIAGRAM MODEL RAC 50YH4 41 ...
Страница 40: ... 43 COMPONENT SIDE SOLDERING SIDE MODEL RAS 50YH4 RECEIVING P W B MARKING ON P W B ...
Страница 41: ... 44 MODEL RAC 50YH4 MAIN P W B Marking on P W B COMPONENT SIDE ...
Страница 90: ... 100 SELF DIAGNOSIS LIGHTING MODE MODEL RAC 50YH4 ...
Страница 108: ... 2 465 56 0 4 0 114 70 6 1 4 5 50Y ...
Страница 110: ... 0 PARTS LIST AND DIAGRAM OUTDOOR UNIT MODEL RAC 50YH4 ...
Страница 112: ...HITACHI SM0226 Printed in Malaysia RAS 50YH4 RAC 50YH4 ...