Lennox LI009HI-230P432, Service Manual

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39
Technical Information
Service Manual
(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 35.6ºF ), 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;
4. Reducing frequency at high speed and power turn-off:
If [T
frequency reducing temperature at high speed of module
]≤T
Module
<[T
Power turn-off temperature of module
] you should adjust the compressor frequency by reducing 30Hz/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;
5. Power turn-off:
If the [T
Power turn-off temperature of module
] ≤T
Module
, you should stop the machine for module overheating protection; If T
Module
<[T
Limited frequency temperature of module
]
and the compressor has been stopped for 3 minutes, the machine should be allowed to operate.
6. If 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 module
] , 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).
(10)Compressor overloads protection
If you measure the compressor overload switch action in 3s, the compressor should be stopped for overloading. The machine should be
allowed to operate after overload protection was measured to resume. If the overloading protection continuously occurs for three times, it
should not be resumed automatically, and you should press the ON/OFF button to resume. The protection times of compressor is allowed to
clear after the compressor run [t
Protection times clearing of compressor overloading
] 30 minutes.
(11)Phase current overcurrent protection of compressor
During the running process of compressor, you could measure the phase current of the compressor, and control it according to the following
steps:
1. Frequency limited
If [I
Limited frequency phase current
] ≤[I
Phase current T frequency reducing phase current
] , you should limit the frequency raising of compressor.
2. Reducing Frequency
If [I
Frequency Reducing Phase Current
]≤I Phase Current<[I
Power Turn-Off Phase Current
], the compressor shall continue to reduce frequency till the lowest frequency
limit or out of the condition of reducing frequency;
3. Power turn-off
If [I
Phase Current
]≥[I
Power Turn-Off Phase Current
], the compressor phase current shall stop working for overcurrent protection; if [I
Phase Current
]≤[I
Frequency Reducing
Phase Current
], and the compressor have stopped working for 3 min, the machine shall be allowed to operate;
4. If the overcurrent protection of compressor phase current 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
Clearing Time of
Compressor Phase Current Times
] , the overcurrent protection is cleared to recount.