Welwyn 4.7kΩ Wire Wound Resistor 3W ±5% W21-4K7JI / 1393275

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