54
12. Protection Control
12.1 Protection Control For All Operations
12.1.1 Restart Control (Time Delay Safety Control)
• The Compressor will not turn on within 3 minutes from the moment operation stops, although the unit is turned on
again by pressing OFF/ON button at remote control within this period.
• This control is not applicable if the power supply is cut off and on again.
• This phenomenon is to balance the pressure inside the refrigerant cycle.
12.1.2 Total Running Current Control
• When the outdoor unit total running current (AC) exceeds X value, the frequency instructed for compressor
operation will be decreased.
• If the running current does not exceed X value for 5 seconds, the frequency instructed will be increased.
• However, if total outdoor unit running current exceeds Y value, compressor will be stopped immediately for 3
minutes.
Model S9NKR S12NKR S18NKR S24NKR S28NKR
A 5.41 6.57 6.57 12.48 12.64
B 5.03 6.13 6.13 12.48 12.14
Cooling/Soft Dry (X)
C 5.03 6.13 6.13 11.46 11.10
Y 15.00 15.00 15.00 19.00 19.00
• The first 30 minutes of cooling operation, (A) will be applied.
12.1.3 IPM (Power Transistor) Prevention Control
• Overheating Prevention Control
o When the IPM temperature rises to 120°C, compressor operation will stop immediately.
o Compressor operation restarts after 3 minutes the temperature decreases to 110°C or 95°C (S24, 28NK).
o If this condition repeats continuously 4 times within 20 minutes, timer LED will be blinking (“F96” is indicated).
• DC Peak Current Control
o When electric current to IPM exceeds set value of 18.5A (S9, 12NK) and 30.0 ± 5.0A (S18NK, S24NK,
S28NK), the compressor will stop operate. Then, operation will restart after 3 minutes.
o If the set value is exceeded again more than 30 seconds after the compressor starts, the operation will
restart after 1 minute.
o If the set value exceeded again within 30 seconds after the compressor starts, the operation will restart after
1 minute. If this condition repeats continuously for 7 times, all indoor and outdoor relays will be cut off, timer
LED will be blinking (“F99” is indicated).