– 81 –
Commanded rotation speed
Actual rotation speed
Acceleration
Deceleration
Acceleration
Deceleration
Rotation speed of compressor
Voltage at HIC
Voltage at HIC
8
9
9
Fig. 8-7
2
3
4
44
64
9
8
47
7
4
6
5
Micro computer
(AX-8E21)
5V
5V
OV
OV
OV
OV
OV
OV
OV
OV
OV
OV
DC current
R806
R201
R205
C206
R211
R206
R207
Q201
Q203
D202
R203
Q202
R208
R222
R204
VRI
FANC
R229
R230
R231
C204
OPI
Power module
positive terminal
Vd
Id
Is
Cool
+
-
+
-
-
+
HIC - 1
ZZZ
+
ZZZ
2
. Voltage amp. circuit
●
The voltage amp. circuit amplifies the DC current level detected by the detection resistor after being
converted to a voltage and supplies it to the micro computer. Receiving this, the micro computer converts
it to a digital signal and compares it with the internal data to judge whether or not overload control is
required.
< During overload control >
●
The filter consisting of R201 and C202 removes high harmonic components from the voltage generated
from the DC current flowing to the detection resistor, and R205 and C206 average the voltage and supplies
it to OP1 pin
5
OP1 forms a non-inverting voltage amp. circuit together with the peripheral elements.
●
The micro computer stores the set values which vary according to the rotation speed as shown in Fig. 8-
8. When the DC current level exceeds the set value, the micro computer enters the overload control state.
The compressor motor is controlled in the same way as in external judgement described previously.
●
The set Value is determined by the amplification of the voltage amp. circuit.
Amplification : high
[
DC current : low
Amplification : low
[
DC current: high
{
Fig. 8-8
Содержание RAC-25CNH11
Страница 35: ... 35 CIRCUIT DIAGRAM MODEL RAS 25CNH11 ...
Страница 36: ... 37 CIRCUIT DIAGRAM MODEL RAC 25CNH11 ...
Страница 104: ... 113 PARTS LIST AND DIAGRAM MODEL RAS 25CNH11 11 2 18 8 20 19 12 63 1 4 60 3 7 14 15 6 5 16 13 88 61 17 9 62 10 ...
Страница 106: ... 115 MODEL RAC 25CNH11 55 22 59 16 26 24 23 20 21 19 13 52 58 53 56 57 2 3 51 15 14 18 4 5 9 6 8 54 17 7 11 10 12 25 ...
Страница 108: ...RAS 25CNH11 RAC 25CNH11 PM NO 0164E Printed in Malaysia HITACHI ...