series circuit
- Thread starter arnold
- Start date
- Status
hurk27
Senior Member
- Location
- Portage, Indiana NEC: 2008
Re: series circuit
1. If one burned out they all go out
2. each would produce about 9.9 watts of light for a total of 99.6 watts if connected to a 120 volt circuit.
3. They would last a loooooong time.
4. They would draw about .83 amps on a 120 volt circuit
Ok I give what was it you wanted to know LOL
[ October 26, 2004, 11:55 PM: Message edited by: hurk27 ]
1. If one burned out they all go out
2. each would produce about 9.9 watts of light for a total of 99.6 watts if connected to a 120 volt circuit.
3. They would last a loooooong time.
4. They would draw about .83 amps on a 120 volt circuit
Ok I give what was it you wanted to know LOL
[ October 26, 2004, 11:55 PM: Message edited by: hurk27 ]
physis
Senior Member
Re: series circuit
Wayne, what did you do with the .1 watt each? And how'd you make that times ten =.4? I know you have a reason for it I just can't figure what.
I'm going with 10 watts total for 1 watt each.
Editted in: Actually they're 100 watts at temperature. Being as how they're not going to get that hot the resistance will be substancially lower. I'm gonna guess around 2.5 or 3 watts each.
[ October 27, 2004, 08:16 AM: Message edited by: physis ]
Wayne, what did you do with the .1 watt each? And how'd you make that times ten =.4? I know you have a reason for it I just can't figure what.
I'm going with 10 watts total for 1 watt each.
Editted in: Actually they're 100 watts at temperature. Being as how they're not going to get that hot the resistance will be substancially lower. I'm gonna guess around 2.5 or 3 watts each.
[ October 27, 2004, 08:16 AM: Message edited by: physis ]
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
Re: series circuit
2. Since they are in series, each bulb would only see 1/10th the voltage. Thus the light output would be about 1/100 of what one would expect at 120V. So they would probably draw about 10W total.
3. Agreed.
4. I would guess the current draw to be more like 0.083 amps.
of course this ignores the fact that as the bulb gets hotter it draws slightly less current, and these bulbs won't ever get hot.
1. Agreed.Originally posted by hurk27:
1. If one burned out they all go out
2. each would produce about 9.9 watts of light for a total of 99.6 watts if connected to a 120 volt circuit.
3. They would last a loooooong time.
4. They would draw about .83 amps on a 120 volt circuit
Ok I give what was it you wanted to know LOL
2. Since they are in series, each bulb would only see 1/10th the voltage. Thus the light output would be about 1/100 of what one would expect at 120V. So they would probably draw about 10W total.
3. Agreed.
4. I would guess the current draw to be more like 0.083 amps.
of course this ignores the fact that as the bulb gets hotter it draws slightly less current, and these bulbs won't ever get hot.
scott thompson
Senior Member
- Location
- Anaheim, California
Re: series circuit
I agree with "Physis" - it would be a total of just about 10 Watts at 120 Volts for all 10 Lamps in Series...
Provided the Fillaments were heated to the operating Temperature which would be found if each Lamp was drawing 100 Watts!
In the normal operation of an individual 100 Watt Incandescent Lamp, the Hot Fillament Resistance per Lamp would be 144.5 Ohms, and the Load Current across the Fillament would be 0.8333... Amperes at 120 Volts, resulting in a 100 Watt draw of True Power from the Supply.
If we could accumulate these values in a series string, then the total Resistance for 10 Lamps would be 1445 Ohms, and the adjusted Load Current would be 0.083 Amperes at 120 Volts - resulting in a True Power of 9.96 Watts drawn from the Power Supply.
Since the Cold Fillament Resistance of these Lamps is drammatically lower than the Hot Fillament Resistance, the real values may be more like in the range of 400% to 2000% of the stuff shown above.
(The Resistance may be as low as 48 Ohms for each Lamp, so the total Resistance would be 480 Ohms, which would allow 0.25 Amperes to flow at 120 Volts - resulting in 30 Watts of Power drawn).
Need to measure the Cold Resistance of some 100 Watt @ 120 Volts Incandescent Lamps, then maybe could post more accurate of an answer!
And to think, this seemed like an easy question to post
Scott35
I agree with "Physis" - it would be a total of just about 10 Watts at 120 Volts for all 10 Lamps in Series...
Provided the Fillaments were heated to the operating Temperature which would be found if each Lamp was drawing 100 Watts!
In the normal operation of an individual 100 Watt Incandescent Lamp, the Hot Fillament Resistance per Lamp would be 144.5 Ohms, and the Load Current across the Fillament would be 0.8333... Amperes at 120 Volts, resulting in a 100 Watt draw of True Power from the Supply.
If we could accumulate these values in a series string, then the total Resistance for 10 Lamps would be 1445 Ohms, and the adjusted Load Current would be 0.083 Amperes at 120 Volts - resulting in a True Power of 9.96 Watts drawn from the Power Supply.
Since the Cold Fillament Resistance of these Lamps is drammatically lower than the Hot Fillament Resistance, the real values may be more like in the range of 400% to 2000% of the stuff shown above.
(The Resistance may be as low as 48 Ohms for each Lamp, so the total Resistance would be 480 Ohms, which would allow 0.25 Amperes to flow at 120 Volts - resulting in 30 Watts of Power drawn).
Need to measure the Cold Resistance of some 100 Watt @ 120 Volts Incandescent Lamps, then maybe could post more accurate of an answer!
And to think, this seemed like an easy question to post
Scott35
Re: series circuit
Posted by petersonra:
The 1 watt per light (with .833 amps flowing) mentioned is the low limit. It assumes the resistance of the lamp is constant.
Without more time to think about this, all I know about the high limit is that it is something less than 100W.
Steve
Posted by petersonra:
I think the cold resistance may be very low. Without knowing the exact Power vs. Resistance curve for the lamps, all we can do is find the limits of the current and wattage.
The 1 watt per light (with .833 amps flowing) mentioned is the low limit. It assumes the resistance of the lamp is constant.
Without more time to think about this, all I know about the high limit is that it is something less than 100W.
Steve
- Location
- Lockport, IL
- Occupation
- Semi-Retired Electrical Engineer
Re: series circuit
To the above discussions, I will add that the total light that they produce will be lower than the light than one would produce on its own (i.e., remove the others from the series circuit).
Let me now repeat Wayne?s question: What was it that you were trying to find out?
To the above discussions, I will add that the total light that they produce will be lower than the light than one would produce on its own (i.e., remove the others from the series circuit).
Let me now repeat Wayne?s question: What was it that you were trying to find out?
- Location
- Massachusetts
Re: series circuit
We should ask the MBTA (they run Boston's subway) while riding the subway through work zones I saw groups of five lamps that look to be a 200 to 300 watts each. These appear to be wired in series and powered off of the third rail. These lamps where being used as work lights.
We should ask the MBTA (they run Boston's subway) while riding the subway through work zones I saw groups of five lamps that look to be a 200 to 300 watts each. These appear to be wired in series and powered off of the third rail.
These lamps where being used as work lights.
- Location
- Massachusetts
Re: series circuit
Paul you are going back away for that song.
I could see these because at the time they had creep through the area under construction.
Paul you are going back away for that song.
I could see these because at the time they had creep through the area under construction.
- Location
- Lockport, IL
- Occupation
- Semi-Retired Electrical Engineer
Re: series circuit
You wouldn't believe how long it took for them to let me off that train. And all for one silly nickle.
Charlie
You wouldn't believe how long it took for them to let me off that train. And all for one silly nickle.
Charlie
hurk27
Senior Member
- Location
- Portage, Indiana NEC: 2008
Re: series circuit
Well I guess I did delete the 0 between the . and the 83
I thought the wattage was a little high
Well I guess I did delete the 0 between the . and the 83
I thought the wattage was a little high
- Status