YASKAWA V1000 Installation Manual page 24

6 Selecting an External Heatsink
NOTICE: Due to uneven compound thickness, uneven heat generation across the heatsink plate or other
factors, the actual heatsink plate temperature (monitored in U4-08) can be slightly different from the
calculated value. An oH drive fault may occur if the heatsink plate temperature exceeds the maximum
allowable value.
◆
Heatsink Selection Example
This example shows heatsink selection for a CIMR-V 2A0006 drive in Normal Duty (ND)
mode.The data required are listed in the table below.
Item
P 27.5 W
Loss
90°C
T
HSP_max
T 40°C
Amb
Rθ 0.05 K/W
HSP
H = 128 mm, D = 68 mm,
A
th
A
0.8 W/(m K)
λ
Thermal conductivity of "Thermal Compound G746" (Shin-Etsu Chemical Co.,
Comp
Ltd)
Rθ
HSP-EHS
Recommended compound thickness: 100 μm
d
Comp
Rθ
HSP_EHS
24
= 0.7 0.128 m 0.068 m = 6.1 10
th
100 μm
=
0.8 W/(m K) × 6.1 × 10
YASKAWA ELECTRIC TOBP C710606 21D YASKAWA AC Drive - V1000 Finless Installation Guide
Value
-3 m 2
= 0.02 K/W
-3 2
m