Electra ELAU-VBZ214-H11, Service Manual

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CONTROL SYSTEM
12-10 Service Manual – VBZ DCI 1-A.1 GB
Deicing interval time is changed as a function of deicing time. If deicing time is shorter than former
deicing time, the deicing interval time will be increased. If deicing time is longer than former deicing
time, the deicing interval time will be decreased.
12.8.6.2 Deicing Protection Procedure
When starting deicing from Heat Mode, system will work as following:
1). Compressor stops. OFAN and RV will be OFF after 40s
3). Compressor starts and deicing time is counted. Compressor frequency will go to Deicing
Frequency.
12.8.6.3 Exiting Deicing
System will exit the deicing until OCT reaches to certain value (depends on OAT) or the
deicing time reaches 12 min as maximum.
12.8.7 Communication malfunction
Connected IDU number detection
If ODU does not receive correct signal from one IDU for 3min continuously, the ODU will
take this IDU as not connected one. But ODU will still send the broadcast to this IDU. If
response were received, then ODU will take it as connected.
12.8.8 IPM module protection
When the compressor starts, if there is over current or control voltage low for IPM module as
some abnormal results, IPM will detect module protection signal as the unit is on. Once the
module protective signal is detected, stop the unit with module protection immediately. If the
module protection is resumed and compressor has stopped for 3min, the unit will be allowed
to operate.
If the module protection continuously occurs for 6 times
(the counter will be cleared after the
compressor has run for 7min) , it can not resume running automatically and display malfunction, it
can resume by power reset.
12.8.9 HP switch protection
If the HP switch is opened for 3S continuously, the system will stop as protection
After the HP switch protection, if HP switch is resumed for continuous 6s, the system
operating can be resumed by power reset.
12.8.10 Module overheating protection
If the module temperature is higher than 95C, the unit will stop. If module temperature is lower than
95C, and compressor has stopped for 3min, the unit will resume operating.
If the unit stops as module overheating protection for 6 times
(the counter will be cleared after the