Dimensioning Climate Control Equipment - Siemens SINAMICS S120 Combi Equipment Manual

12.9.3

Dimensioning Climate Control Equipment

Cabinet manufacturers provide calculation programs for selecting climate control equipment.
It is always necessary to know the power loss of the components and equipment installed in
the cabinet.
The physical relationship is shown in the following example.
Calculating the thermal power to be dissipated: q = Q - k x A x ΔT
with
q = thermal power that has to be dissipated using a cooling unit [W]
Q = power loss [W]
∆T = difference between the room temperature and the temperature inside the cabinet [K]
k = heat transfer coefficient, e.g. sheet-steel, painted 5.5 [W/(m
A = free-standing cabinet surface area [m
Table 12- 17 Example, calculating the power loss of a drive configuration
Component
SINUMERIK 828D
Line filter
Line reactor
S120 Combi 3 axes Power
Module 20 kW
Motor Module 9 A
Motor Module 18 A
SMC
SITOP 20
Line contactor
Total:
Assumption:
free-standing control cabinet surface A = 5 m
difference between the room temperature and the temperature inside the control cabinet ∆T
= 10 K
q = 1146.8 W - 5.5 W / (m
SINAMICS S120 Combi
Manual, (GH9), 07/2016, 6SL3097-4AV00-0BP5
Number Total power loss [W]
(including electronic losses)
1 28
1 16
1 98
1 634
1 100,4
1 185,4
2 10
1 53
1 12
K) * 5 m
2
12.9 Note on control cabinet cooling
]
2
2
* 10 K = 871.8 W
2
Cabinet design and EMC
* K)]
2
Total power loss [W]
28
16
98
634
100,4
185,4
20
53
12
1146,8
315