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Old October 7th 06, 07:39 PM posted to alt.home.repair
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Default Fluorescent amperage

How much current is drained by a 2x 40 watt T12 magnetic ballasted
shop light trough at peak current draw? I assume this is at startup,
while trying to saturate the transformer and ignite the tubes. How
much
is drawn once the lights are running?

Short version: How many such fixtures (too cheap to replace
the old ones) can be run on a 15 amp circuit?


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Old October 7th 06, 09:15 PM posted to alt.home.repair
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Default Fluorescent amperage

On 7 Oct 2006 10:39:25 -0700, "Father Haskell"
wrote:

How much current is drained by a 2x 40 watt T12 magnetic ballasted
shop light trough at peak current draw? I assume this is at startup,
while trying to saturate the transformer and ignite the tubes. How
much is drawn once the lights are running?


I don't know


Short version: How many such fixtures (too cheap to replace
the old ones) can be run on a 15 amp circuit?


15A x 120V = 1800W
You can only use 80% 1800W x 0.8 = 1400W
(2x40) = 80W per fixture
1400W / 80W = 18

18


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Old October 7th 06, 09:16 PM posted to alt.home.repair
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Default Fluorescent amperage

15a x 80% = 12 a.
Different ballasts will have a small margin in amp draw per ballast.

Does it not say on the ballast amps?



How much current is drained by a 2x 40 watt T12 magnetic ballasted
shop light trough at peak current draw? I assume this is at startup,
while trying to saturate the transformer and ignite the tubes. How
much
is drawn once the lights are running?

Short version: How many such fixtures (too cheap to replace
the old ones) can be run on a 15 amp circuit?

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Old October 7th 06, 09:59 PM posted to alt.home.repair
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Default Fluorescent amperage


How much current is drained by a 2x 40 watt T12 magnetic ballasted
shop light trough at peak current draw? I assume this is at startup,
while trying to saturate the transformer and ignite the tubes. How
much
is drawn once the lights are running?

Short version: How many such fixtures (too cheap to replace
the old ones) can be run on a 15 amp circuit?


I have an old textbook that says to allow 20% of the total lamp
wattage rating for power to the ballast. That would mean 1.20 x 2 x
40 watts = 96 watts total power consumed (not appartent power) for a
simple dual-40 fixture.

Maybe the new electronic ballasts are more efficient than this?

Beachcomber



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Old October 7th 06, 10:30 PM posted to alt.home.repair
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Default Fluorescent amperage


The electronics are a lot better.
Less amp draw
Less heat
The frequency on the output of the ballasts driving the lamps makes it
better on the eyes.
On the ones I have installed anyway.



Maybe the new electronic ballasts are more efficient than this?

Beachcomber


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Old October 7th 06, 11:55 PM posted to alt.home.repair
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Default Fluorescent amperage

Most building codes require limiting lighting to 80% of the circuit
load. The idea is that it could be on for long time and things will
heat up. It also allows for the fairly minor start-up issues. For a 15A
breaker at 120V thats 1440watts.

Your ballast should state it's amperage on the lable. Beachcombers 96W
is about right. Any way you look at it you get quite a few fixtures! If
you are running many fixtures for any length of time you can save a lot
of money with new fixtures. ( 2 "T8" lamps, give more light, last
longer and usually need about 0.52 amps. That's almost half the power!)

Richard Reid, LC
Luminous Views

Beachcomber wrote:
How much current is drained by a 2x 40 watt T12 magnetic ballasted
shop light trough at peak current draw? I assume this is at startup,
while trying to saturate the transformer and ignite the tubes. How
much
is drawn once the lights are running?

Short version: How many such fixtures (too cheap to replace
the old ones) can be run on a 15 amp circuit?


I have an old textbook that says to allow 20% of the total lamp
wattage rating for power to the ballast. That would mean 1.20 x 2 x
40 watts = 96 watts total power consumed (not appartent power) for a
simple dual-40 fixture.

Maybe the new electronic ballasts are more efficient than this?

Beachcomber


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Old October 8th 06, 12:43 AM posted to alt.home.repair
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Default Fluorescent amperage

On Sat, 07 Oct 2006 19:16:36 GMT, Tazz wrote:

15a x 80% = 12 a.


and `1800W x`80% = 1440W.

Different ballasts will have a small margin in amp draw per ballast.

Does it not say on the ballast amps?



How much current is drained by a 2x 40 watt T12 magnetic ballasted
shop light trough at peak current draw? I assume this is at startup,
while trying to saturate the transformer and ignite the tubes. How
much
is drawn once the lights are running?

Short version: How many such fixtures (too cheap to replace
the old ones) can be run on a 15 amp circuit?

--
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http://notstupid.laughingsquid.com

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force for atheism ever conceived." -- Isaac Asimov
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Old October 8th 06, 02:30 AM posted to alt.home.repair
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Default Fluorescent amperage


Beachcomber wrote:
How much current is drained by a 2x 40 watt T12 magnetic ballasted
shop light trough at peak current draw? I assume this is at startup,
while trying to saturate the transformer and ignite the tubes. How
much
is drawn once the lights are running?

Short version: How many such fixtures (too cheap to replace
the old ones) can be run on a 15 amp circuit?


I have an old textbook that says to allow 20% of the total lamp
wattage rating for power to the ballast. That would mean 1.20 x 2 x
40 watts = 96 watts total power consumed (not appartent power) for a
simple dual-40 fixture.


So I could just round up to a nice, easy 100 watts per fixture and
calculate from there. Thanks.


Maybe the new electronic ballasts are more efficient than this?

Beachcomber


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Old October 8th 06, 02:51 PM posted to alt.home.repair
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Default Fluorescent amperage

On 7 Oct 2006 10:39:25 -0700, "Father Haskell"
wrote:

How much current is drained by a 2x 40 watt T12 magnetic ballasted
shop light trough at peak current draw? I assume this is at startup,
while trying to saturate the transformer and ignite the tubes. How
much
is drawn once the lights are running?

Short version: How many such fixtures (too cheap to replace
the old ones) can be run on a 15 amp circuit?



I believe you need to check each ballast power rating, not the bulbs.

Also, you have to figure if the usage is continous, or not continous
loads.

later,

tom @ www.NoCostAds.com



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