Welwyn 4.7Ω Wire Wound Resistor 3W ±5% W21-4R7JI

As there is a maximum temperature to which the wire can rise during an overload, if the resistor is already dissipating heat, then the pulse energy applied should be less than that allowed by the graph. Using the formula below we can estimate the “equivalent” energy of a pulse applied to a resistor that is already dissipating power.It should also be noted that for repetitive pulses the average power dissipated must not exceed the continuous power rating of the resistor.

CECC approved
Suitable for harsh environments
Impervious lead free vitreous enamel coating
Overload characteristics ideal for protection circuits
High stability and reliability
High power dissipation for size
Suitable for harsh environments
Impervious lead free vitreous enamel coating
Overload characteristics ideal
for protection circuits
High stability and reliability
High power dissipation for size