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- How does leaving the ballast and capacitor in circuit affect power factor of LED lights?

A poster on another forum has fitted a large number of 230V 50Hz 24W nominal LED tubes, apparently designed to be plugged straight into the old fluorescent fittings.

He has found, by clamp meter measurement, that the new LED lights appear to be consuming 80W, not the claimed 24W.

A number of us pointed out the difference between apparent power as measured by the clamp meter, and real power as charged by the power company, and the possible effects of leaving the ballast and capacitor in circuit.

An engineer from the supplier has visited, and merely measured the consumption by clamp meter again. I would be very interested in the input from members on here.

May I link the thread here?: https://www.mig-welding.co.uk/forum...florescent-led-replacement-efficiency.128634/

edit: I should add that this class of LED tube must have a minimum power factor of 0.5. In my scribblings, I have (for now) modelled them as 24W resistive loads. It might be more meaningful to assume a 0.5 (leading?) PF and calculate the complex impedance of the tubes as such.

He has found, by clamp meter measurement, that the new LED lights appear to be consuming 80W, not the claimed 24W.

A number of us pointed out the difference between apparent power as measured by the clamp meter, and real power as charged by the power company, and the possible effects of leaving the ballast and capacitor in circuit.

An engineer from the supplier has visited, and merely measured the consumption by clamp meter again. I would be very interested in the input from members on here.

May I link the thread here?: https://www.mig-welding.co.uk/forum...florescent-led-replacement-efficiency.128634/

edit: I should add that this class of LED tube must have a minimum power factor of 0.5. In my scribblings, I have (for now) modelled them as 24W resistive loads. It might be more meaningful to assume a 0.5 (leading?) PF and calculate the complex impedance of the tubes as such.

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