2 What is an fault arc - Die BG ETEM
2 What is an fault arc - Die BG ETEM
2 What is an fault arc - Die BG ETEM
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Summary of symbols<br />
a mm Exposure d<strong>is</strong>t<strong>an</strong>ce, working d<strong>is</strong>t<strong>an</strong>ce<br />
ATPV cal/cm 2 or kJ/m 2<br />
Arc Thermal Perform<strong>an</strong>ce Value<br />
cP Ws*m 2 /kg*K Specific heat<br />
d mm Electrode gap<br />
dTmax K Delta peak temperature (maximum temperature<br />
r<strong>is</strong>e)<br />
EBT50 cal/cm 2 or kJ/m 2<br />
Break-open incident energy (50 % value)<br />
Ei<br />
kJ/m 2 or cal/cm 2<br />
Incident energy<br />
Ei0<br />
kJ/m 2 or cal/cm 2<br />
Direct exposure incident energy<br />
kJ/m 2 or cal/cm 2<br />
Tr<strong>an</strong>smitted incident energy<br />
Eit<br />
fT<br />
Tr<strong>an</strong>sm<strong>is</strong>sion function<br />
I"k A Prospective subtr<strong>an</strong>sient short-circuit current<br />
(rms value)<br />
I"k3p A Prospective three-phase short-circuit current<br />
(subtr<strong>an</strong>sient)<br />
I"k3pmax A Maximum prospective three-phase short-circuit<br />
current (subtr<strong>an</strong>sient)<br />
I"k3pmin A Minimum prospective three-phase short-circuit<br />
current (subtr<strong>an</strong>sient)<br />
IkLB A Actual <strong>arc</strong>ing <strong>fault</strong> short-circuit current<br />
iLB A Arc current, inst<strong>an</strong>t<strong>an</strong>eous value<br />
IN A Fuse rated current<br />
kB<br />
Current attenuation factor<br />
kP<br />
Normalized <strong>arc</strong> power<br />
kPmax<br />
Maximum value of the normalized <strong>arc</strong> power<br />
Tr<strong>an</strong>sm<strong>is</strong>sion factor<br />
kT<br />
kU<br />
Voltage factor<br />
m kg Mass<br />
P<strong>arc</strong> = PLB kW Arc active power<br />
R Ohm Res<strong>is</strong>t<strong>an</strong>ce (of the network imped<strong>an</strong>ce)<br />
R/X Imped<strong>an</strong>ce ration, res<strong>is</strong>t<strong>an</strong>ce-to-react<strong>an</strong>ce ratio<br />
S"k MVA Short-circuit capacity<br />
t s time<br />
t<strong>arc</strong> = tk s Arc duration, short-circuit duration (clearing time)<br />
tmax s Time to delta peak temperature, time period of<br />
heat tr<strong>an</strong>sfer<br />
UB V Arc voltage (me<strong>an</strong> value)<br />
ULB V Arc voltage, inst<strong>an</strong>t<strong>an</strong>eous value<br />
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