Accelnet Plus Micro Modules User Guide
16-01687 Rev 03
Copley Controls
Page 29 of 139
O
PERATING
T
EMPERATURE AND
C
OOLING
C
ONFIGURATIONS
The temperature rise due to Watts of dissipation depends on the
thermal resistance
of the
drive which depends on the mounting and cooling means. Thermal energy (heat) will move
from a hot location to a colder one much in the way that water does. Given the drive heat
and environment heat as constants, the rate at which heat moves depends on thermal
resistance in units of degrees-C per Watt and expressed as Rth. As Rth goes down,
speeding the flow of heat out of the drive, the temperature rise in the drive will be reduced.
Factors affecting Rth are the area of the surface of the drive and the movement of air over
the surfaces. Conduction through solid materials is another path for heat flow. Forced air
over the drive or heatsink surfaces will increase the flow of heat as will mounting of the
drive’s heatplate to a metal surface.
T
HERMAL
R
ESISTANCE VS
.
M
OUNTING
&
C
OOLING
These tables show the thermal resistance Rth in degrees-C per Watt (C/W) for typical
mounting and cooling configurations. LFM is Linear Feet per Minute, the velocity of air flow
produced by a fan directed in line with the heatsink fins.
N
O
H
EATSINK
LFM
0
100
200
300
Rth
8.5
6.5
5.5
4.0
P
INS
H
EATSINK
A-A
IRFLOW
LFM
0
100
200
300
Rth
4.2
2.9
1.8
1.4
P
INS
H
EATSINK
B-A
IRFLOW
LFM
0
100 200 300
Rth
-
4.2
2.6
1.9
T
ALL
P
INS
H
EATSINK
A-A
IRFLOW
LFM
0
100
200
300
Rth
2.0
1.3
0.9
0.7
T
ALL
P
INS
H
EATSINK
B-A
IRFLOW
LFM
0
100
200
300
Rth
-
2.2
1.4
1.1
Note:Tall pins heatsink not shown
