Specifications

72
6. LEV
RP8, 10
Control modes RemarksControl details
6-2. Normal control
LEV opening pulse will be controlled according to the change of compressor
operating frequency and regulated to adjust the SC to let the target SC range.
• Control timing: Once per minute after 3 minutes have passed since the
compressor started.
• Opening pulse range: The following range is specified according to the
compressor operating frequency.
• Opening pulse range corresponding to the change of compressor operating
frequency
Opening pulse range = Amount of frequency change O 2.5 pulse
• Opening pulse range corresponding to the SC setting : Max. i 9 pulse
• Compressor start-up
Opening pulse will be adjusted according to only the change of frequency
during 3 minute start-up. However, when the outdoor temperature is -5: or
less, LEV opening pulse is fixed to 460 pulse for 1 minute.
Discharge super
heat temp. is
calculated from
discharge temp.
(TH4) and indoor
cond./eva. temp.
(TH5).
Refer to 8-1. for
the relation
between target
SC and target
SC step.
SC is calculated
from discharge
temp. (TH4) and
indoor liquid
temp. (TH2).
6-7. Others
1 LEV opening pulse is set to 400 while the compressor is being stopped.
2 After LEV opening pulse is initialized to 0 by making 700 pulse down from
the present pulse, set the pulse to 400.
Compressor
frequency
49Hz or less
50Hz to 75Hz
76Hz to 90Hz
91Hz or more
110~ 300
110~350
120~400
120~460
PUHZ-RP8, 10YHA
Opening pulse range (Lower limit to upper limit)
6-1. Target sub cool (SC)
Compressor operating frequency < 60Hz Target SC step = 2
Compressor operating frequency ] 60Hz Target SC step = 2
6-3.Target SC correction by discharge temperature (TH4)
The target SC is corrected according to the discharge temperature.
• Range of discharge temperature (TH4) correction : 100:~105:
• Range of correction in step of target SC : - 1~0
6-4.Target SC correction by discharge super heat
The target SC is corrected according to the discharge super heat.
• Range of discharge super heat correction : 10:~15:
• Range of correction in step of target SC : 0~+1
6-5.Lower opening correction by discharge temperature (TH4)
The lower opening of LEV is corrected according to the discharge temperature (TH4).
• Range of discharge temperature (TH4) correction : 115: or more
• Amount of correction of lower opening : +10pulse (every minute, Max.+30 Pulse)
6-6.Lower opening correction by discharge super heat
• Range of discharge super heat correction : 50: or more
•
Amount of correction of lower opening : +10pulse (every minute, Max. +100 Pulse)
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