Service manual

109
15
Backup Operation
Emergency Operation
Fault of inverter unit (Backup setup of Master outdoor unit)
Outline
When an inverter unit fails, firstly perform emergency process according to the following work
procedure, and then perform emergency operation by a fixed-speed unit only.
Work procedure
(1) First, turn off the power source of all the outdoor units which are connected to
the system.
(2) The following works are performed to the failed inverter unit.
1) Close service valve of gas pipe fully. (Fully close by turning clockwise)
2) If refrigerant leakage occurs on PMVB, close the service valve of the liquid pipe fully.
(Fully close by turning clockwise)
3) Check service valve of the balancing pipe is opened fully.
(Fully open by turning counterclockwise)
4) Remove "Short-circuit connector" connected to [CN604] on the interface P.C. board.
The removed "Short-circuit connector" is used for the fixed-speed unit. (Described in item
(4) below.)
5) [In case of fault of compressor/fault of electric part system]
a. Works to the failed inverter unit is complete.
b. Then, keep the power source OFF.
c. When central management remote controller is connected to the inverter unit, the
central management remote controller cannot be used.
6) [In case of fault of other cycle part system]
a. Set DIP SW06/Bit 1, 2, 3, 4 on the interface P.C. board to ON.
(LED display changes to U0)
b. Failed inverter work is complete.
c. Then, turn on the power source to protect the compressor.
(Turn on winding heater)
d. The central management remote controller can be used as normal.
(3) Select a master outdoor unit among the fixed-speed units according to the
following reference.
1) When only one fixed-speed unit is connected, select it as the master outdoor unit.
2) When two or more fixed-speed units are connected, select one connected to the nearest
position of the inverter unit as the master outdoor unit.
(4) Perform the following works for the fixed-speed unit selected as the master
outdoor unit.
1) Insert "Short-circuit connector" into [CN604] on the interface P.C. board.
(One removed from the inverter unit as (2), 4))
2) Set DIP SW07/Bit 3 on the interface P.C. board to ON.
(Setup to correct oil recovery capacity)
3) Set DIP SW08/Bit 2 on the interface P.C. board to ON.
(Setup to select master outdoor unit)
(5) Turn on the power source of each outdoor unit.
(6) Emergency process is complete. The operation then starts by a command from the
indoor unit.