Specifications

Control Specification SiUS12-928_A
57 Function and Control
Detail Detect Disconnection
When the starting control (630 seconds) finishes, and the 9-minute timer for the compressor
operation continuation is not counting time, the following adjustment is made.
1. When the operation mode is cooling
When the discharge pipe temperature is lower than the outdoor heat exchanger temperature,
the discharge pipe thermistor disconnection is ascertained.
2. When the operation mode is heating
When the discharge pipe temperature is lower than the maximum temperature of operating
room heat exchanger, the discharge pipe thermistor disconnection is ascertained.
Adjustment when the thermistor is disconnected
When the compressor stops repeatedly, the system is down.
3.12.11Control when frequency is changed
When the target discharge pipe temperature control is active, if the target frequency is changed for
a specified value in a certain time period, the target discharge pipe temperature control is canceled
and the target opening of the electronic expansion valve is changed.
3.13 Malfunctions
3.13.1 Sensor Malfunction Detection
Sensor malfunction may occur either in the thermistor or current transformer (CT) system.
Relating to Thermistor Malfunction
1. Outdoor heat exchanger thermistor
2. Discharge pipe thermistor
3. Fin thermistor
4. Gas pipe thermistor
5. Outdoor temperature thermistor
6. Liquid pipe thermistor
Relating to CT Malfunction
When the output frequency is more than Hz, and the input current is less than A, abnormal
adjustment is carried out.
3.13.2 Detection of Overcurrent and Overload
Outline In order to protect the inverter, an excessive output current is detected, the OL temperature is
observed to protect the compressor.
Detail  If the inverter current exceeds 30 A, the system shuts down the compressor.
 If the OL (compressor head) temperature exceeds 120 ~ 130°C (216 ~ 266°F), the compressor
stops.
18 class 24/32 class
(Hz) 55 32
(A) 1.25 0.5