Cableizer ®

Operating point ratio

IEC 60853-2, Section 8.1, Note of eq. 8-2.

Symbol
$r_{2R}$
Unit
-
Formulas
$\frac{\theta_{max}-\theta_a-\Delta \theta_{d,t}}{\delta \theta_{R,\infty}}$
Related
$\Delta \theta_{d,t}$
Transient temperature rise by dielectric losses [K]
$\delta \theta_{R,\infty}$
Max permissible conductor temperature rise in the steady-state [°C]
$\theta_a$
Ambient temperature [°C]
$\theta_{max}$
Highest temperature of conductor over a load variation period [°C]
Used in
$I_{c,2}$
Emergency overload current [A]