Re: ((OT)) Electronics (electrical) Problem
 

That's what I needed to know. the supply I bought is way too small.

And, the bulb is 250w not 250a. Sorry for that.




"doane_nut" <nospam@nospam.com> wrote in message
news:465ce1f2$0$4700$4c368faf@roadrunner.com...
> Jeff,
>
> 250A (A=Amps) is ALOT of current, so much so that it can't be correct. You
> probably have no more than a 250A service for your entire house. I think
> you mean W (Watts), which is usually how bubs are rated; by the Voltage
> and Watts. The amps required, based on Ohms Law, is the Watts divided by
> the voltage. The bulb you have is 250W divided by 24 Volts = 10.42 Amps.
>
> Sounds like the power supply you bought only puts out about 1.666A at 24V
> (24V X 1.66A = 40VA). So, the power supply is too small. You need one
> rated at 10A plus a few more Amps for a margin of safety, so at 24V output
> the VA is 24V X 10A = 240VA minimum.
>
> Howard
>
>
> "Jeff Strickland" <crwlr@verizon.net> wrote in message
> news:6R27i.2970$J76.2363@trndny03...
>>I thought I knew this stuff, but there is a nuance that I'm not getting.
>>
>> I have a fiber optic lighting system in my swimming pool. It takes a
>> 24v/250A light bulb. The bubl does not light, but the filiment is okay.
>> The power supply (transformer) does not put out any voltage, so I bought
>> a new one.
>>
>> The new transformer is stated to provide 40VA, but the light does not
>> come on. My guess is that a VA and a "regular" A are different. What's
>> the difference?
>>
>>
>>
>>
>>
>>
>>
>
>

Re: ((OT)) Electronics (electrical) Problem
 

That's what I needed to know. the supply I bought is way too small.

And, the bulb is 250w not 250a. Sorry for that.




"doane_nut" <nospam@nospam.com> wrote in message
news:465ce1f2$0$4700$4c368faf@roadrunner.com...
> Jeff,
>
> 250A (A=Amps) is ALOT of current, so much so that it can't be correct. You
> probably have no more than a 250A service for your entire house. I think
> you mean W (Watts), which is usually how bubs are rated; by the Voltage
> and Watts. The amps required, based on Ohms Law, is the Watts divided by
> the voltage. The bulb you have is 250W divided by 24 Volts = 10.42 Amps.
>
> Sounds like the power supply you bought only puts out about 1.666A at 24V
> (24V X 1.66A = 40VA). So, the power supply is too small. You need one
> rated at 10A plus a few more Amps for a margin of safety, so at 24V output
> the VA is 24V X 10A = 240VA minimum.
>
> Howard
>
>
> "Jeff Strickland" <crwlr@verizon.net> wrote in message
> news:6R27i.2970$J76.2363@trndny03...
>>I thought I knew this stuff, but there is a nuance that I'm not getting.
>>
>> I have a fiber optic lighting system in my swimming pool. It takes a
>> 24v/250A light bulb. The bubl does not light, but the filiment is okay.
>> The power supply (transformer) does not put out any voltage, so I bought
>> a new one.
>>
>> The new transformer is stated to provide 40VA, but the light does not
>> come on. My guess is that a VA and a "regular" A are different. What's
>> the difference?
>>
>>
>>
>>
>>
>>
>>
>
>

Re: ((OT)) Electronics (electrical) Problem
 

That's what I needed to know. the supply I bought is way too small.

And, the bulb is 250w not 250a. Sorry for that.




"doane_nut" <nospam@nospam.com> wrote in message
news:465ce1f2$0$4700$4c368faf@roadrunner.com...
> Jeff,
>
> 250A (A=Amps) is ALOT of current, so much so that it can't be correct. You
> probably have no more than a 250A service for your entire house. I think
> you mean W (Watts), which is usually how bubs are rated; by the Voltage
> and Watts. The amps required, based on Ohms Law, is the Watts divided by
> the voltage. The bulb you have is 250W divided by 24 Volts = 10.42 Amps.
>
> Sounds like the power supply you bought only puts out about 1.666A at 24V
> (24V X 1.66A = 40VA). So, the power supply is too small. You need one
> rated at 10A plus a few more Amps for a margin of safety, so at 24V output
> the VA is 24V X 10A = 240VA minimum.
>
> Howard
>
>
> "Jeff Strickland" <crwlr@verizon.net> wrote in message
> news:6R27i.2970$J76.2363@trndny03...
>>I thought I knew this stuff, but there is a nuance that I'm not getting.
>>
>> I have a fiber optic lighting system in my swimming pool. It takes a
>> 24v/250A light bulb. The bubl does not light, but the filiment is okay.
>> The power supply (transformer) does not put out any voltage, so I bought
>> a new one.
>>
>> The new transformer is stated to provide 40VA, but the light does not
>> come on. My guess is that a VA and a "regular" A are different. What's
>> the difference?
>>
>>
>>
>>
>>
>>
>>
>
>

Re: ((OT)) Electronics (electrical) Problem
 

The power rating given for small transformers is usually the max allowed
load for short periods and not for continuous operation at full load.
If you operate the lamp for long periods of time, you need (rough
estimation) a transformer capable of continuous power load of 250W / 0.8 ~=
310VA. Which depening of the quality of the transformer, means you might
need a 500VA transformer if you want it to last.

Bill Spiliotopoulos.

? "Jeff Strickland" <crwlr@verizon.net> ?????? ??? ??????
news:6R27i.2970$J76.2363@trndny03...
>I thought I knew this stuff, but there is a nuance that I'm not getting.
>
> I have a fiber optic lighting system in my swimming pool. It takes a
> 24v/250A light bulb. The bubl does not light, but the filiment is okay.
> The power supply (transformer) does not put out any voltage, so I bought a
> new one.
>
> The new transformer is stated to provide 40VA, but the light does not come
> on. My guess is that a VA and a "regular" A are different. What's the
> difference?
>
>
>
>
>
>
>

Re: ((OT)) Electronics (electrical) Problem
 

The power rating given for small transformers is usually the max allowed
load for short periods and not for continuous operation at full load.
If you operate the lamp for long periods of time, you need (rough
estimation) a transformer capable of continuous power load of 250W / 0.8 ~=
310VA. Which depening of the quality of the transformer, means you might
need a 500VA transformer if you want it to last.

Bill Spiliotopoulos.

? "Jeff Strickland" <crwlr@verizon.net> ?????? ??? ??????
news:6R27i.2970$J76.2363@trndny03...
>I thought I knew this stuff, but there is a nuance that I'm not getting.
>
> I have a fiber optic lighting system in my swimming pool. It takes a
> 24v/250A light bulb. The bubl does not light, but the filiment is okay.
> The power supply (transformer) does not put out any voltage, so I bought a
> new one.
>
> The new transformer is stated to provide 40VA, but the light does not come
> on. My guess is that a VA and a "regular" A are different. What's the
> difference?
>
>
>
>
>
>
>

Re: ((OT)) Electronics (electrical) Problem
 

The power rating given for small transformers is usually the max allowed
load for short periods and not for continuous operation at full load.
If you operate the lamp for long periods of time, you need (rough
estimation) a transformer capable of continuous power load of 250W / 0.8 ~=
310VA. Which depening of the quality of the transformer, means you might
need a 500VA transformer if you want it to last.

Bill Spiliotopoulos.

? "Jeff Strickland" <crwlr@verizon.net> ?????? ??? ??????
news:6R27i.2970$J76.2363@trndny03...
>I thought I knew this stuff, but there is a nuance that I'm not getting.
>
> I have a fiber optic lighting system in my swimming pool. It takes a
> 24v/250A light bulb. The bubl does not light, but the filiment is okay.
> The power supply (transformer) does not put out any voltage, so I bought a
> new one.
>
> The new transformer is stated to provide 40VA, but the light does not come
> on. My guess is that a VA and a "regular" A are different. What's the
> difference?
>
>
>
>
>
>
>

Re: ((OT)) Electronics (electrical) Problem
 

The power rating given for small transformers is usually the max allowed
load for short periods and not for continuous operation at full load.
If you operate the lamp for long periods of time, you need (rough
estimation) a transformer capable of continuous power load of 250W / 0.8 ~=
310VA. Which depening of the quality of the transformer, means you might
need a 500VA transformer if you want it to last.

Bill Spiliotopoulos.

? "Jeff Strickland" <crwlr@verizon.net> ?????? ??? ??????
news:6R27i.2970$J76.2363@trndny03...
>I thought I knew this stuff, but there is a nuance that I'm not getting.
>
> I have a fiber optic lighting system in my swimming pool. It takes a
> 24v/250A light bulb. The bubl does not light, but the filiment is okay.
> The power supply (transformer) does not put out any voltage, so I bought a
> new one.
>
> The new transformer is stated to provide 40VA, but the light does not come
> on. My guess is that a VA and a "regular" A are different. What's the
> difference?
>
>
>
>
>
>
>

Re: Re: ((OT)) Electronics (electrical) Problem
 

On Wed, 30 May 2007 02:02:04 GMT, "Jeff Strickland"
<crwlr@verizon.net> wrote:

>My meter told me the bulb was good, but now I am not sure about the meter.
>Maybe the meter is okay, but the moron working the buttons leaves a bit to
>be desired. In any case, the bulb is dead, and the original power supply is
>putting out voltage.


Two thing, a 40VA replacement transformer is not going to power a 250
watt bulb. Next, a 250 watt 24 volt bulb is going to read about a dead
short on ohm test (much less than 1 ohm) While it will look like about
a 1.5 ohm load when hot, resistance decreases when element is cold so
do not be surprized if it look like or near a dead short on a 1x
scale. BTW, a 24volt 250 watt bulb is a pretty serious bulb and can
get pretty warm.
-----------------
TheSnoMan.com

Re: Re: ((OT)) Electronics (electrical) Problem
 

On Wed, 30 May 2007 02:02:04 GMT, "Jeff Strickland"
<crwlr@verizon.net> wrote:

>My meter told me the bulb was good, but now I am not sure about the meter.
>Maybe the meter is okay, but the moron working the buttons leaves a bit to
>be desired. In any case, the bulb is dead, and the original power supply is
>putting out voltage.


Two thing, a 40VA replacement transformer is not going to power a 250
watt bulb. Next, a 250 watt 24 volt bulb is going to read about a dead
short on ohm test (much less than 1 ohm) While it will look like about
a 1.5 ohm load when hot, resistance decreases when element is cold so
do not be surprized if it look like or near a dead short on a 1x
scale. BTW, a 24volt 250 watt bulb is a pretty serious bulb and can
get pretty warm.
-----------------
TheSnoMan.com

Re: Re: ((OT)) Electronics (electrical) Problem
 

On Wed, 30 May 2007 02:02:04 GMT, "Jeff Strickland"
<crwlr@verizon.net> wrote:

>My meter told me the bulb was good, but now I am not sure about the meter.
>Maybe the meter is okay, but the moron working the buttons leaves a bit to
>be desired. In any case, the bulb is dead, and the original power supply is
>putting out voltage.


Two thing, a 40VA replacement transformer is not going to power a 250
watt bulb. Next, a 250 watt 24 volt bulb is going to read about a dead
short on ohm test (much less than 1 ohm) While it will look like about
a 1.5 ohm load when hot, resistance decreases when element is cold so
do not be surprized if it look like or near a dead short on a 1x
scale. BTW, a 24volt 250 watt bulb is a pretty serious bulb and can
get pretty warm.
-----------------
TheSnoMan.com