Answer / dilshad

UPF: Unity power factor. Used when circuit is resistive.
LPF: Low power factor. Used when circuit in inductive or capacitive (when pf in near to zero).

Answer / sridhar

lpf is stands for lagging power factor and upf stands for unity power factor and lpf where used in pure inductive load oriented where as upf where used in pure resistive load oriented. This is the main difference usage in experiments.

Answer / k .balaji singh

As we know the difference between upf and lpf as for resistive loads we use upf as resistive loads are which rise in temperature while passing current in electrical and in mechanical the break drum is a resistive load so while coming to inductive load which we use lpf low power factor wattemeter as inductive loads as inductor which does not draw that much current comare to resistor.

Answer / shoeb

my dear friend . UPF stands for unity power factor and LPF means low power factor . we have UPF or near UPF when we are dealing with capacitance and WE have LPF when we are dealing with inductance because in the case of capacitans powerfactor lead and in the case of inductance powerfactor will lag ..... this is the difference b/w UPF & LPF

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