Siemens HT 8 - Connecting; Pin Assignment of the Interfaces

Guidelines
If the convection area A [m
2
] does not suffice for the "heat dissipation using natural convection",
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
Ltot
for
thermally critical applications can be determined as follows:
– Current measurement for a 24 V supply voltage
– Power loss P
Ltot
[W] = U (24 V) * |measured value in ampères|
● 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
2
- T
1
= ΔT ≥ 10K.
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Figure 1-2 Calculating heat dissipation for PCU 50.5 with OP 019
General information and networking
1.2 Application planning
Handheld Terminal HT 8
22 Manual, 07/2015, A5E36371621B-AB