Elmo BUT- X/YYY User Manual

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Whistle 100 Series Power Dissipation
0.0
1.0
2.0
3.0
4.0
5.0
6.0
0
0.
5
1
1.
5
2
2.
5
3
3.
5
4
4.
5
5
Peak Current (A)
P
o
w
e
r D
is
s
ip
a
ti
o
n
 (W
)
85VDC
70VDC
50VDC
 
3.10.1.3  How to Use the Charts 
The charts above are based upon theoretical worst-case conditions.  Actual test results show 
30% - 50% better power dissipation.  
To determine if your application needs a heatsink: 
1.  Allow maximum heatsink temperature to be 80 
°C or less. 
2.  Determine the ambient operating temperature of the Butterfly. 
3.  Calculate the allowable temperature increase as follows:  
• 
for an ambient temperature of 40 
°C ,  ∆T= 80 °C – 40 °C = 40 °C  
4.  Use the chart to find the actual dissipation power of the drive. Follow the voltage 
curve to the desired output current and then find the dissipated power.  
5.  If the dissipated power is below 4 W the Butterfly will need no additional cooling. 
Note:   The chart above shows that no heatsink is needed when the heatsink temperature is 
80
°C, ambient temperature is 40 °C and heat dissipated is 4 Watts: 
 
3.10.2 Dragonfly 
The best way to dissipate heat from the Dragonfly is to mount it so that its lower board faces 
upwards. For best results leave approximately 10 mm of space between the Dragonfly's lower 
board and any other assembly.  
 
 
Standard 40 
°°°°C Ambient Temp.
 
External 
Heatsink 
Required 
Heatsink 
not 
Required 
Butterfly -100
Dragonfly/ Butterfly Installation Guide 
Installation 
MAN-DRBUIG (Ver. 1.1) 
 
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