Fedders GWH18MC-D3DNA1A/O, Service Manual

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30
Function and Control
,
5. Power turn-off:
If the T
Power turn-off temperature during discharging
≤T
Discharge
, you should discharge to protect machine stopping; If T
Discharge
T
Limited frequency temperature during discharging
and the compressor has been stopped for 3 minutes, the machine
should be allowed to operate.
6 . If the discharging temperature protection of compressor continuously occurs for six times, it should not be
resumed automatically, and you should press the ON/OFF button to resume. During the process of running, if the
running time of compressor exceeds the t
Protection times clearing of discharge
, the discharge protection is cleared to
recount. Stopped or transferred to supply air mode will clear the trouble times immediately (if the trouble can not
be resumed, mode transferring also will not clear it).
7. Frequency limited
If I
Limited frequency when overcurrent
≤I
AC Electric current
I
frequency reducing when overcurrent
, you should limit the frequency
raising of compressor.
8. Reducing frequency:
If I
Frequency reducing when overcurrent
≤I
AC Electric current
I
Power turn-off when overcurrent
, you should reduce the compressor
frequency till the lower limit or exit the frequency reducing condition;
9. Power turn-off:
If I
Power turn-off machine when overcurrent
≤I
AC Electric current
, you should carry out the overcurrent stopping protection; If I
AC Electric current
T
Limited frequency when overcurrent
and the compressor has been stopped for 3 minutes, the machine
should be allowed to operate.
10. If the overcurrent protection continuously occurs for six times, it should not be resumed automatically, and you
should press the ON/OFF button to resume. During the process of running, if the running time of compressor
exceeds the t
Protection times clearing of over
c
urrent
, the discharge protection is cleared to recount.
(6)Voltage sag protection
After start the compressor, if the time of DC link Voltage sag U
Sagging protection voltage
is measured to be less than
t
Voltage sag protection time
, the machine should be stop at once, hand on the voltage sag trouble, reboot
automatically after 30 minutes.
(7)Communication fault
When you have not received any correct signal from the inner machine in three minutes, the machine will stop for
communication fault.
When you have not received any correct signal from driver IC (aim to the controller for the separating of main
control IC and driver IC), and the machine will stop for communication fault. If the communication is resumed, the
machine will be allowed to operate.
(8)Module protection
Testing the module protective signal immediately after started, once the module protective signal is measured,
stop the machine with module protection immediately. If the module protection is resumed, the machine will be
allowed to operate.
If the module protection continuously occurs for three times, it should not be resumed automatically, and you
should press the ON/OFF button to resume. If the running time of compressor exceeds the t
Protection times clearing of
module
, the module protection is cleared to recount.
(9)Module overheating protection
1. Starting estimation:
After the compressor stopped working for 180s, if T
Module
T
Module frequency limited temperature
(the temperature of
hysteresis is 2 ), the machine is allowed to start, otherwise it should not be started, and should be stopped to
treat according to the module overheating protection:
The machine should be stopped or transferred to supply air, the trouble should be cleared immediately, and the
protection times are not counted.
2. Frequency limited
If T
Limited frequency temperature of module
≤T
Module
T
frequency reducing temperature at normal speed of module
, you should limit the
frequency raising of compressor.
3. Reducing frequency at normal speed and power turn-off:
If T
frequency reducing temperature at normal speed of module
≤T
Module
T
frequency reducing temperature at high speed of module
, you should
adjust the compressor frequency by reducing 8Hz/90s till the lower limit; After it was running 90s at the lower limit,
if T
frequency reducing temperature at normal speed of module
≤T
Module
, you should stop the machine for module overheating
protection;
2. Frequency limited
If T
Limited frequency temperature of module
≤T
Module
T
frequency reducing temperature at normal speed of module
, you should limit the
frequency raising of compressor.
3. Reducing frequency at normal speed and power turn-off: