53
Control modes
Remarks
Control details
4-2. Low discharge super heat temperature protection control
Set a small value for the targeted opening pulse according to the discharge
super heat temperature.
• Correction range of the discharge super heat temperature : 10
:
or less
• This control does not work for 3 or 7 minutes after the compressor gets started.
Discharge super heat
temp. is calculated from
discharge temp. (TH4)
and outdoor cond./eva.
temp. (TH6).
4-3. Evaporation protection control
20 pulse will be added to the present opening pulse in the condition written below.
Outdoor condenser/evaporator temperature (TH6) - Outdoor liquid pipe
temperature (TH3)
]
6
:
W
This control does not work for 3 or 7 minutes after the compressor gets started.
4-4. Others
1
LEV opening pulse is set to 400 while the compressor is being stopped.
2
After LEV opening pulse is initialized to 400 by making 700 pulse down from
the present pulse, set the pulse to 400.
4. LEV(A)
4-1. Normal control
LEV opening pulse will be controlled every minute to adjust the discharge
temperature in order to let the intake super heat temperature be 0
:
to 5
:
.
• Control timing: Once per minute after 3 or 7 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 = Present opening pulse
o
(Target frequency /
Operating frequency -1)
o
0.8
• Compressor start-up
Opening pulse will be adjusted according to only the change of frequency
during 3 or 7 minute start-up.
The start-up control time will be changed according to the discharge
temperature (TH4).
Discharge temperature (TH4)
]
30
:
: 3 minute start-up
Discharge temperature (TH4) < 30
:
: 7 minute start-up
Compressor
frequency
49Hz or less
50Hz to 75Hz
76Hz to 90Hz
91Hz to more
80 ~ 250
95 ~ 350
130 ~ 400
130 ~ 480
55 ~ 250
85 ~ 350
100 ~ 400
125 ~ 480
70 ~ 300
90 ~ 350
100 ~ 400
120 ~ 480
PUHZ-RP2.5, 3VHA
PUHZ-RP1.6, 2VHA
PUHZ-RP4,5,6VHA
Opening pulse range (Lower limit to upper limit)
OCT04A-2.qxp 04.9.29 9:15 AM Page 53
