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Temperature of screen

The formulae to calculate the loss factor for screen $\lambda_1$ use the resistance of the screen $R_{sh}$ at its maximum operating temperature. Because the temperature of the screen is a function of the current, $I_c$, an iterative method is used for the calculation.

With crossing heat sources, a temperature rise of $\Delta\theta_{0x}$ applies at the hottest point.

Symbol
$\theta_{sc}$
Unit
°C
Formulae
$\theta_c-T_1 \left(W_c+\frac{W_d}{2}\right)$
Related
$\Delta \theta_{0x}$
Temperature rise by crossing heat sources [K]
$T_1$
Thermal resistance between one conductor and sheath [K.m/W]
$\theta_c$
Temperature of conductor [°C]
$W_c$
Conductor losses [W/m]
$W_d$
Dielectric losses [W/m]
Used in
$R_{sc}$
Electrical resistance of screen [$\Omega$/m]
$\theta_{spf}$
Mean temperature of the medium in the steel pipe [°C]