Gree GMV5 Series Service Manual page 321

8. Troubleshooting
8.1 Hardware Faults
Table 6. Hardware faults
Symptom
A software communication
fault alarm is reported, and
some or all units' running
state is not displayed or
cannot be controlled.
Though lines are normal,
a software communication
fault occurs and some or
all units' information is not
displayed.
Though lines and devices
are normal, information of
devices of a floor is not
displayed.
A communication fault alarm
is reported, all units' running
state is not displayed,
and the TX LED on the
converter is steadily on.
Lines, devices, and setups
are all normal. However, a
software communication
fault alarm is reported.
8.2 Software Faults
8.2.1 Software Abnormalities
1. Though the username and password entered are correct, the system prompts ―Please contact the
administrator‖, as shown in the following figure:
GMV5 DC INVERTER VRF UNITS SERVICE MANUAL
Possible Cause
The communications lines
are not twisted pairs.
Gateway damages.
Communication lines
interrupt.
Communication lines are
short circuited.
Twisted pairs are too close
to the power lines (less than
15 cm clearance), resulting
in disturbance that affects
communication.
Communication interface
connection error
ODUs, after being replaced
with chips or reset with DIP,
are not re-powered on.
The serial port configured
by the software is
inconsistent with that
connected to PCs.
Units are not powered on.
ODUs or IDUs are not
equipped with chips, or
chips are inversely installed.
Unit address is incorrect or
replicate.
Maybe a repeater is
required. If such a device
has been installed, maybe
wiring is incorrect.
Polarities of communication
lines are not distinguished
or they are connected in a
wrong order.
The display or controller
does not match units.
Troubleshooting
Replace the communication
lines with twisted pairs.
Replace the damaged
gateway.
Weld the interrupted lines.
Repair the short circuited
part.
Separate the two types of
lines. If their clearance is
less than 15 cm, cover them
with sheath separately.
Refer to related instructions
to connect the
communication interfaces.
Re-power on the ODUs.
Connect the PCs to the
serial port configured by the
software or change the serial
port setting in the software.
Power on the units.
Install the chips in a correct
direction and power on the
units.
Correct the incorrect
address settings.
Reinstall the repeater in a
correct manner.
Check communication lines
for their polarities and
connect them in a correct
order.
Check the models of the
controller and operation
panel. If they do not match
unit specification, replace
them.
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