Cableizer

Thermal resistance tray

Thermal resistance of tray to account for increase in the air temperature inside the tray to the ambient air temperature.

Symbol
$T_{tray}$
Unit
K.m/W
Formulas
$\frac{1}{3p_{tr}}$IEC 60287-2-1
$\frac{0.2}{w_{t}+0.705h_{t}}$IEE Wiring Regulations BS 7671
$\frac{\pi \rho_{4}}{2\left(2+\frac{\pi w_{t}}{2t_{t}}+\ln\left(\left(\frac{t_{t}}{2\left(t_{t}+h_{t}\right)}\right)^2\right)\right)}$Slaninka I
$\frac{1}{\frac{2\left(2\left(1-\ln2\right)+\frac{\pi w_{t}}{2t_{t}}\right)}{\pi \rho_{t}}-\frac{2\ln\left(\left(\frac{t_{t}}{2\left(t_{t}+h_{t}\right)}\right)^2\right)}{\pi \rho_{4}}+\frac{2\ln2}{\pi \rho_{4}}}$Slaninka II
Related
$h_{t}$
Height (inner) [m]
$p_{tr}$
Effective perimeter trough [m]
$\pi$
Archimedes' constant $\pi$
$\rho_{4}$
Thermal resistivity soil [K.m/W]
$\rho_{t}$
Thermal resistivity wall [K.m/W]
$t_{t}$
Thickness wall [m]
$w_{t}$
Width (inner) [m]
Choices
IdMethodInfo
0IEC 60287-2-1method 0
1IEE Wiring Regulations BS 7671method 1
2Slaninka Imethod 2
3Slaninka IImethod 3