Capacitor in parallel with a resistor between live and full bridge rectifier
$begingroup$
I have an LED light bulb and dismantled it to look at the circuit inside.
I made some google search for pcb but couldn't find any relevant info about FST-855 or FST-854:
After drawing the schematic, I could not figure out what is the purpose of some of the elements. Here is the schematic (sorry for hand drawing):
I was expecting to see the electrolytic cap however did not understand the reason for film cap. Can you tell me why there is this "capacitor in parallel with a resistor" in between Live and full wave rectifier?
led capacitor
asked 4 hours ago
user458835user458835
62
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$endgroup$
add a comment |
$begingroup$
I have an LED light bulb and dismantled it to look at the circuit inside.
I made some google search for pcb but couldn't find any relevant info about FST-855 or FST-854:
After drawing the schematic, I could not figure out what is the purpose of some of the elements. Here is the schematic (sorry for hand drawing):
I was expecting to see the electrolytic cap however did not understand the reason for film cap. Can you tell me why there is this "capacitor in parallel with a resistor" in between Live and full wave rectifier?
led capacitor
asked 4 hours ago
user458835user458835
62
New contributor
user458835 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
2
$begingroup$
A helpful search term: "capacitive dropper"
$endgroup$
– Hearth
3 hours ago
add a comment |
$begingroup$
I have an LED light bulb and dismantled it to look at the circuit inside.
I made some google search for pcb but couldn't find any relevant info about FST-855 or FST-854:
After drawing the schematic, I could not figure out what is the purpose of some of the elements. Here is the schematic (sorry for hand drawing):
I was expecting to see the electrolytic cap however did not understand the reason for film cap. Can you tell me why there is this "capacitor in parallel with a resistor" in between Live and full wave rectifier?
led capacitor
asked 4 hours ago
user458835user458835
62
New contributor
user458835 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
I have an LED light bulb and dismantled it to look at the circuit inside.
I made some google search for pcb but couldn't find any relevant info about FST-855 or FST-854:
After drawing the schematic, I could not figure out what is the purpose of some of the elements. Here is the schematic (sorry for hand drawing):
I was expecting to see the electrolytic cap however did not understand the reason for film cap. Can you tell me why there is this "capacitor in parallel with a resistor" in between Live and full wave rectifier?
led capacitor
led capacitor
asked 4 hours ago
user458835user458835
62
New contributor
user458835 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 4 hours ago
user458835user458835
62
New contributor
user458835 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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edited 3 hours ago
user458835
asked 4 hours ago
user458835user458835
62
New contributor
user458835 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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asked 4 hours ago
user458835user458835
62
asked 4 hours ago
user458835user458835
62
62
New contributor
user458835 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
user458835 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
user458835 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
2
$begingroup$
A helpful search term: "capacitive dropper"
$endgroup$
– Hearth
3 hours ago
add a comment |
2
$begingroup$
A helpful search term: "capacitive dropper"
$endgroup$
– Hearth
3 hours ago
2
2
$begingroup$
A helpful search term: "capacitive dropper"
$endgroup$
– Hearth
3 hours ago
$begingroup$
A helpful search term: "capacitive dropper"
$endgroup$
– Hearth
3 hours ago
add a comment |
1 Answer
1
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votes
$begingroup$
Welcome to Electrical Engineering!
The point of the capacitor is to limit the current through the full bridge rectifier. According to the “824J400V” indication, it is a 820nF capacitor. Its impedance at 50Hz is 3882Ω. It will limit the current to less than 62mA at 240V.
The point of the resistor in parallel is to discharge the capacitor when the bulb is disconnected.
answered 3 hours ago
user2233709user2233709
868210
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add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Welcome to Electrical Engineering!
The point of the capacitor is to limit the current through the full bridge rectifier. According to the “824J400V” indication, it is a 820nF capacitor. Its impedance at 50Hz is 3882Ω. It will limit the current to less than 62mA at 240V.
The point of the resistor in parallel is to discharge the capacitor when the bulb is disconnected.
answered 3 hours ago
user2233709user2233709
868210
$endgroup$
add a comment |
$begingroup$
Welcome to Electrical Engineering!
The point of the capacitor is to limit the current through the full bridge rectifier. According to the “824J400V” indication, it is a 820nF capacitor. Its impedance at 50Hz is 3882Ω. It will limit the current to less than 62mA at 240V.
The point of the resistor in parallel is to discharge the capacitor when the bulb is disconnected.
answered 3 hours ago
user2233709user2233709
868210
$endgroup$
add a comment |
$begingroup$
Welcome to Electrical Engineering!
The point of the capacitor is to limit the current through the full bridge rectifier. According to the “824J400V” indication, it is a 820nF capacitor. Its impedance at 50Hz is 3882Ω. It will limit the current to less than 62mA at 240V.
The point of the resistor in parallel is to discharge the capacitor when the bulb is disconnected.
answered 3 hours ago
user2233709user2233709
868210
$endgroup$
Welcome to Electrical Engineering!
The point of the capacitor is to limit the current through the full bridge rectifier. According to the “824J400V” indication, it is a 820nF capacitor. Its impedance at 50Hz is 3882Ω. It will limit the current to less than 62mA at 240V.
The point of the resistor in parallel is to discharge the capacitor when the bulb is disconnected.
answered 3 hours ago
user2233709user2233709
868210
answered 3 hours ago
user2233709user2233709
868210
answered 3 hours ago
user2233709user2233709
868210
answered 3 hours ago
user2233709user2233709
868210
868210
add a comment |
add a comment |
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2
$begingroup$
A helpful search term: "capacitive dropper"
$endgroup$
– Hearth
3 hours ago