YASKAWA GA500 series, Руководство по установке, Страница: 26 / 28

8 External Heatsink Selection
26 YASKAWA TOEP C710617 0SA YASKAWA AC Drive GA500 Installation Manual
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Select External Heatsink by Thermal Resistance
Replace the value of Table 8.1 into the formula in Select External Heatsink by Thermal
Resistance on page 24 .
The thermal resistance of the external heatsink “ EF(98) L: 150 “ is 1.6 K/W, so you can use it.
Yaskawa recommends the external heatsink "EK (95) L: 150" to prevent overheat if there is a
temporary temperature increase or a decrease in the cooling capacity of the external heatsink
because of dust and unwanted material.
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Examine Feasibility of the Selected External Heatsink
The thermal resistance of the external heatsink “ EF (98) L: 150 “ is 1.6 K/W. You can use the
formula to calculate the heatsink plate temperature.
The temperature of the heatsink plate is lower than the maximum value of 90 °C, so you can use
it. Because the thermal transfer area is 70% of the drive mounting area, and the environmental
conditions can change because dust and unwanted material can decrease the cooling capacity of
the external heatsink, Yaskawa recommends
“ EK (95) L: 150 ” heatsink to achieve Rθ
EHS
= 1.1
K/W (T
HSP
= 68.95 °C).