Control Box Cooling System - Mitsubishi Electric CITY MULTI PQRY-P200YMF-B Service Handbook

[2] Control box cooling system

In PQRY, in order to cool the parts in the control box which emit heat, a refrigerant evaporator has been placed in
the bottom of the control box (unit frame side). (See the figure.)
The control box is also mounted in the frame and when the inverter operates, it operates the control box internal
cooling fan as well as supplying refrigerant to the evaporator, thus creating air passages in the direction shown by
the arrows.
(1) Cooling fan control
(a) If the temperature of fin is over 80°C when the inverter is just
turned on, run the fan until the temperature drops below 80°C.
During this operation, turning on the inverter is prohibited.
(b) When the inverter is operating
(c) Once the fan goes on, it forcibly remains ON for 5 minutes.
Note: By mounting the control box in the frame, a structure is
created where air passages are formed, so when mount-
ing the control box, be sure to push it in to the back.
Also, at that time, be careful of tearing of the seal
material affixed to the frame.
(2) LEV 2 control
(a) LEV2 control range.
0 LEV 2 150 pulses
(b) LEV2 Control method
SHB=THINV-TH2
6 SHB
SHB < 6
Always ON
THHS TH10
– –
THHS 55˚C –
THHS < 55˚C TH10 > 80
TH10 80
–54–
Cooling fan
TRM
Heat sink
DS
THINV
Refrigerant piping
Evaporator
LEV2
TH2
(INV Cooling LEV)
PQRY Control Box Layout Diagram
(Internal air passages)
LEV2
UP
UP
UP
DOWN
PQRY
Control box
DCL
Frame