eem2am
Banned
rating of capacitor used in cfl
hello
I have just taken apart a (240V rms, 50Hz) 15W Compact fluorescent bulb and done tests on it. The Input DC Bus has 110V of ripple on it (DC Bus goes from 220V to 330V with 10ms period.
It's DC bus (following the diode bridge) has one 3.3uF , 400V electrolytic capacitor on it. It is Aishi GA series cap:-
**broken link removed**
This cap has 99mA of ripple current capability.
However since the DC bus has 110V of ripple on it this means that the RMS charging current alone into this cap is 82mA......The discharging current will add to that, definetely taking the total RMS capacitor current to above 100mA.
This means that this cap is not properly rated for its ripple current.
Do you know why they have put in a cap thats not properly rated ?
Won't it fail prematurely ?
(Strangley, despite the bulb's packet saying "15W", .....on the bulb itself it is written "230V, 144mA"....which is 33 Watts )
hello
I have just taken apart a (240V rms, 50Hz) 15W Compact fluorescent bulb and done tests on it. The Input DC Bus has 110V of ripple on it (DC Bus goes from 220V to 330V with 10ms period.
It's DC bus (following the diode bridge) has one 3.3uF , 400V electrolytic capacitor on it. It is Aishi GA series cap:-
**broken link removed**
This cap has 99mA of ripple current capability.
However since the DC bus has 110V of ripple on it this means that the RMS charging current alone into this cap is 82mA......The discharging current will add to that, definetely taking the total RMS capacitor current to above 100mA.
This means that this cap is not properly rated for its ripple current.
Do you know why they have put in a cap thats not properly rated ?
Won't it fail prematurely ?
(Strangley, despite the bulb's packet saying "15W", .....on the bulb itself it is written "230V, 144mA"....which is 33 Watts )