Mitsubishi Electric 500YEMK-A, Руководство по обслуживанию

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Item
At compressor is started
Compressor stopped during cool-
ing or heating mode
After operation has been stopped
During defrosting (( ❇ 1) in Fig below)
During oil recovery operation
When low pressure saturation
temperature (TH2) has dropped
during lower limit frequency opera-
tion(15 minutes after start)
When the high pressure (Pd) is
risen up during lower limit fre-
quency operation (3 minutes after
starting)
When the discharge temperature
(Td) is risen up
TH2 – 15˚C
Pd 2.26 MPa
and
after 30 seconds
Pd
1.96 MPa
Td 115˚C
❇ Example of operation of SV1
Compressor
Bypass
solenoid
valve (SV1)
(4-minute)
(2-minute) (4-minute) (3-minute)
Start Thermo.
OFF Thermo.
ON Defrost Stop
2) Bypass solenoid valves (SV1, SV4) [Both SV1 and SV4 are on (open)]
<Variable capacity unit>
SV1
ON OFF
ON for 4 minutes
ON
ON for 3 minutes
ON
ON during oil recovery operation after con-
tinuous low-frequency compressor opera-
tion.
—
—
—
TH2 – 30˚C
Pd 2.26 MPa
ON when the high
pressure (Pd) ex-
ceeds the control
pressure limit.
• Td 130˚C
and
• Pd
1.96 MPa
or
TH2 –
10˚C
SV4
ON OFF
—
—
—
Normally ON
—
Pd 2.70 MPa
Pd 2.35 MPa
and
after 30 seconds