Standards And Approvals - Siemens SINUMERIK 840D sl Manual

Technical specifications

7.4 Standards and approvals

Guidelines
If the convection area A [m
then use:
● "Heat dissipation using natural convection and internal turbulence" for hot spots and heat
concentrations in housings subject to space constraints. The total power loss P
thermally critical applications can be determined as follows:
– Current measurement for a 24 V supply voltage
– Power loss P
● Heat dissipation using open-circuit ventilation
Calculation of the volumetric flow
The power loss (thermal) dissipated by the components in an operator unit is to be dissipated
using open-circuit ventilation. The volumetric flow V required for this should be calculated at a
difference in temperature of T
Figure 7-2
7.4 Standards and approvals
Approvals
CE approval
Figure 7-3
86
] does not suffice for the "heat dissipation using natural convection",
2
[W] = U (24 V) * |measured value in ampères|
Ltot
- T = ΔT ≥ 10K.
2 1
Calculating heat dissipation for PCU 50.5 with OP 019
CE marking
for
Ltot
Operator panel front: OP 012
Manual, 05/2019, A5E36371591B AB