Hitachi RAS-25QH1 Technische Information Seite 177

Detection resistor DC current
380V
R463A CHOP-HIC er
09 RI16A
c2
ov
Fig. 9-6
— es
Fig. 9-7
Set voltage
Voltage at micro computer pin @
Rotation speed of compressor Commanded rotation speed
Actual rotation speed
Acceleration
(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>
e@ The filter consisting of R463A and C2 removes high harmonic components from the voltage generated
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