Function And Operation Of Protective Procedures - Sharp AH-X108E Service Manual

AH/AU-X108E
AY/AE-X108E
AH/AU-X138E
AY/AE-X138E
(2) DC overcurrent detection, AC overcurrent detection
To protect against overcurrent due to sudden
changes in load, the compressor is stopped if the set
value (29 A: AE-X138E, AU-X138E / 24 A: AE-
X108E, AU-X108E) DC is exceeded in the DC
section, or the set value (15 A: AE-X138E, AU-
X138E / 11 A: AE-X108E, AU-X108E)AC is
exceeded in the AC section. In this case, the outdoor
fan does not stop, and 170 seconds after operation is
stopped, another try will be made. Three retries are
allowed. On the fourth retry, a complete stop request
signal is sent to the indoor unit, and the outdoor unit
will remain stopped until reset is performed. At this
time, the 3-minute delay for control of the outdoor unit
will not function; therefore, do not cancel by removing
the plug and cutting the power.
2-4 Compressor protector control
If the temperature of the compressor chamber
exceeds 114°C, the compressor is stopped. In this
case, the outdoor fan does not stop, and when the
compressor chamber temperature decreases to
100°C three minutes after operation is stopped,
another try will be made. Three retries are allowed.
On the fourth retry, a complete stop request signal is
sent to the indoor unit, and the outdoor unit will

FUNCTION AND OPERATION OF PROTECTIVE PROCEDURES

Function
NO
Stops operation if no revolution pulse
Indoor
signal is input from the indoor fan motor
fan lock
for one minute.
1
Stops operation if the revolution pulse
Indoor fan signal from the indoor fan indicates low
rpm error
rpm (approximately 300 rpm or less).
Lowers the operating frequency if the
temperature of the indoor heat exchanger
Indoor
2
goes below 5°C during cooling. Stops the
freezing
compressor if the temperature stays
guard
below 0°C for 4 minutes.
Lowers the operating frequency if the
temperature of the indoor heat exchanger
rises above the overheating temperature
during heating. Stops the compressor if the
Indoor
temperature stays above the overheating
3 overheating
temperature for 1 minute at minimum
control
frequency.
Set values for overheating temperature
During normal operation: 51°C to 54°C
During full power operation: 54°C to
58°C
Stops the compressor if a current of
approximately 29A/24A
DC
[AY-X138E/AY-X108E] or more flows in the
overcurrent
4
power transistor module. Also stops the
or overheat
compressor if the temperature of the power
of the IPM
transistor module is exceeds 110°C.
Operation
Detection
Description
time
When indoor
fan is revolving
During cooling
and dry
During heating
During
compressor
operation
30
remain stopped until reset is performed. At this time,
the 3-minute delay for control of the outdoor unit will
not function; therefore, do not cancel by removing the
plug and cutting the power.
2-5 Power transistor module protector
If the temperature of the chips in the power transistor
module exceeds 110 °C, the compressor is stopped.
In this case, the outdoor fan does not stop, and when
the temperature of the chips in the power transistor
module decreases to 110 °C 170 seconds after
operation is stopped, another try will be made. Three
retries are allowed. On the fourth retry, a complete
stop request signal is sent to the indoor unit, and the
outdoor unit will remain stopped until reset is
performed. At this time, the 3-minute delay for control
of the outdoor unit will not function; therefore, do not
cancel by removing the plug and cutting the power.
2-6 Serial signals
(1) Serial signals consist of all 96-bit signals.
(2) If the outdoor unit does not receive a serial signal, it
will stop approximately 30 seconds later. Note that this
is true only of normal operation; in test mode, it does
not stop and operation takes place based on the test
mode commands.
Restart
condition
Operation OFF
Automatically restarts when
the exchange temperature
rises above the freezing
prevention temperature
(above 2°C)
Automatically restarts when
the exchange temperature
goes below the overheating
temperature.
Automatically restarts after
safety time (170 seconds)
Self diagnostic
display
Restart
Indoor Outdoor
times
No limit Yes No
No limit No No
No limit No No
4 times Yes Yes