Mitsubishi Electric MR-J5D, Руководство пользователя

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5 CHARACTERISTICS
5.2 Power supply capacity and generated loss
95
5
Heat dissipation area for enclosed type cabinet
For the heat dissipation area of the converter unit, refer to "Heat dissipation area for enclosed type cabinet" in the following
manual.

MR-CV Power Regeneration Converter Unit User's Manual
The enclosed type cabinet (hereafter called the cabinet) that stores the drive unit should be designed to ensure that its
internal temperature rise is 15 °C at an ambient temperature of 40 °C. Calculate the necessary heat dissipation area
of the cabinet with the equation below (10.1) while allowing a margin of approximately 5 °C for a maximum ambient
temperature of 60 °C.
A: Heat dissipation area [m
2
]
P: Loss generated in the cabinet [W]

T: Difference between internal and ambient temperatures [°C]
K: Heat dissipation coefficient [5 to 6]
When calculating the heat dissipation area with the equation (10.1), assume that P is the sum of all losses generated in the
cabinet. For the amount of heat generated by the drive unit, refer to the following.

Page 94 Amount of heat generated by the drive unit
"A" indicates the effective area for heat dissipation, but if the cabinet is directly installed on an insulated wall, that extra
amount must be added to the cabinet's surface area. The required heat dissipation area will vary with the conditions in the
cabinet. If convection in the cabinet is poor and heat builds up, effective heat dissipation will not be possible. Therefore,
arrangement of the equipment in the cabinet and the use of a cooling fan should be considered. The following page contains
information on the required heat dissipation area (estimated) of drive unit cabinets when operating amplifiers at a rated load in
ambient temperatures of 40 °C.

Page 94 Amount of heat generated by the drive unit
When air flows along the outer wall of the cabinet, effective heat exchange is possible, because the temperature slope inside
and outside the cabinet is steeper.
K • Δ T
P
A = ∙ ∙ ∙ (10.1)
(Outside the
cabinet)
(Inside the cabinet)
Air flow